Novità bibliografiche

Si comunica che oggi l'EFSA ha pubblicato le seguenti 2 opinion : “La macellazione del pollame” e “L’abbattimento nel pollame per scopi diversi dalla macellazione”. La pubblicazione dei due pareri è accompagnata dal relativo comunicato dell’EFSA.

L'EFSA ha individuato le misure per ridurre i rischi legati al mancato rispetto del benessere degli animali durante la macellazione del pollame e le operazioni di abbattimento del pollame effettuato nell’ambito delle attività di controllo delle malattie.
Sono state valutate tutte le fasi del processo : arrivo e scarico degli uccelli, stordimento, dissanguamento, abbattimento. Vengono indentificati una serie di pericoli per il benessere, quali il dolore, la sete, la fame o le limitazioni nel movimento - e, ove possibile, vengono proposte misure preventive e correttive.
La maggior parte dei pericoli sono il risultato di carenze del personale, ad es. mancanza di formazione e di personale specializzato. Viene sottolineata l’importanza di formare adeguatamente il personale nelle diverse fasi della macellazione e di una chiara identificazione dei ruoli e delle responsabilità.
I nuovi pareri scientifici sono i primi di una serie di aggiornamenti sul benessere degli animali da macello richiesti dal Commissione europea. L'EFSA pubblicherà ulteriori pareri nel 2020 su suini (marzo), bovini (giugno) e altre specie (Dicembre).
I risultati saranno utilizzati dalla Commissione europea nelle discussioni con l’OIE mirate ad allineare gli approcci al benessere degli animali al macello.

Scientific Report on avian influenza overview September–November 2017.

This report includes (on page 14) the previously circulated, updated list of wild bird species targeted for passive surveillance of H5 HPAI viruses in the EU.

Newcastle disease is caused by virulent strains of Newcastle disease virus (NDV), which causes substantial morbidity
and mortality events worldwide in poultry. The virus strains can be differentiated as lentogenic, mesogenic, or
velogenic based on a mean death time in chicken embryos. Currently, velogenic strains of NDV are not endemic in
United States domestic poultry; however, these strains are present in other countries and are occasionally detected
in wild birds in the U.S. A viral introduction into domestic poultry could have severe economic consequences due to
the loss of production from sick and dying birds, the cost of control measures such as depopulation and disinfection
measures, and the trade restrictions that would likely be imposed as a result of an outbreak. Due to the disease-free
status of the U.S. and the high cost of a potential viral incursion to the poultry industry, a qualitative risk analysis was
performed to evaluate the vulnerabilities of the U.S. against the introduction of virulent strains of NDV. The most likely
routes of virus introduction are explored and data gathered by several federal agencies is provided. Recommendations
are ultimately provided for data that would be useful to further understand NDV on the landscape and to utilize
all existing sampling opportunities to begin to comprehend viral movement and further characterize the risk of NDV
introduction into the U.S.

Vienna R. Brown and Sarah N. Bevins

Vet Res (2017) 48:68 DOI 10.1186/s13567-017-0475-9

Antimicrobial resistance (AMR) is a global health threat, and antimicrobial usage and
AMR in animal production is one of its contributing sources. Poultry is one of the most
widespread types of meat consumed worldwide. Poultry flocks are often raised under
intensive conditions using large amounts of antimicrobials to prevent and to treat disease,
as well as for growth promotion. Antimicrobial resistant poultry pathogens may result in
treatment failure, leading to economic losses, but also be a source of resistant bacteria/
genes (including zoonotic bacteria) that may represent a risk to human health. Here we
reviewed data on AMR in 12 poultry pathogens, including avian pathogenic Escherichia
coli (APEC), Salmonella Pullorum/Gallinarum, Pasteurella multocida, Avibacterium paragallinarum,
Gallibacterium anatis, Ornitobacterium rhinotracheale (ORT), Bordetella avium,
Clostridium perfringens, Mycoplasma spp., Erysipelothrix rhusiopathiae, and Riemerella
anatipestifer. A number of studies have demonstrated increases in resistance over time
for S. Pullorum/Gallinarum, M. gallisepticum, and G. anatis. Among Enterobacteriaceae,
APEC isolates displayed considerably higher levels of AMR compared with S. Pullorum/
Gallinarum, with prevalence of resistance over >80% for ampicillin, amoxicillin, tetracycline
across studies. Among the Gram-negative, non-Enterobacteriaceae pathogens,
ORT had the highest levels of phenotypic resistance with median levels of AMR against
co-trimoxazole, enrofloxacin, gentamicin, amoxicillin, and ceftiofur all exceeding 50%.
In contrast, levels of resistance among P. multocida isolates were less than 20% for all
antimicrobials. The study highlights considerable disparities in methodologies, as well
as in criteria for phenotypic antimicrobial susceptibility testing and result interpretation.
It is necessary to increase efforts to harmonize testing practices, and to promote free
access to data on AMR in order to improve treatment guidelines as well as to monitor
the evolution of AMR in poultry bacterial pathogens.

Nguyen Thi Nhung, Niwat Chansiripornchai and Juan J. Carrique-Mas

Front. Vet. Sci. 4:126. doi: 10.3389/fvets.2017.00126

Infectious bronchitis is considered to be one of the most devastating diseases in poultry. Control of its spread is typically attempted through biosecurity measures and extensive vaccination. However, the remarkable genetic and antigenic variability of the virus, which originate from both mutations and recombination events, represents an unsolved challenge for this disease. The present study reports on the emergence and spread of recombinant clusters detected in Italy and Spain between 2012 and 2014. A total of 36 Spanish and Italian infectious bronchitis virus (IBV) field strains were investigated and genetically characterized using phylogenetic, molecular, recombination and selection pressure analyses of the complete S1 gene. Based on the partial S1 sequencing, 27 IBV strains originating from Spain and nine from Italy were initially classified as being closely related to the Guandong/Xindadi (XDN) genotype. Phylogenetic analysis of the complete S1 gene revealed that the XDN strains formed a homogeneous clade with the Spanish IBV isolates within the QX genotype, whereas there was higher variability within the Italian strains. Recombination analysis determined that these strains belonged to four groups, which originated from independent recombination events between the QX and 793B IBV genotypes. Our data support the hypothesis of two different scenarios: firstly, in Spain, the large and homogeneous clade probably originated from a single offspring of the recombinant founder, which became dominant and spread throughout the country. Secondly, the nine Italian recombinants, which are characterized by three different recombination patterns, probably represent less fitted strains, because they were less viable with respect to their recombinant parents.

Ana Moreno, G. Franzo, P. Massi, G. Tosi, A. Blanco, N. Antilles, M. Biarnes, N. Majó, M. Nofrarías, R. Dolz, D. Lelli, E. Sozzi, A. Lavazza, and M. Cecchinato

Avian Pathology Vol. 46 , Iss. 1,2017

Summary
-------
AGoose/Guangdong/96 lineage H5N8 highly pathogenic avian influenza
(HPAI) virus of clade 2.3.4.4 was detected in migratory birds at Lake Ubsu-Nur in the Tyva Republic of the Russian Federation, located on the Central Asian Flyway, in early June 2016 (World Organisation for Animal Health (OIE), 2016; Department for Environment, Food and Rural Affairs, 2016).

In past seasons, detection of HPAI virus in this region of the Russian Federation was followed by detection of similar viruses in other locations, especially to the west and south of the Tyva Republic. All countries along this flyway and those to the west in the former Soviet Republics, the Middle East, Eastern Europe and even Africa (especially West Africa) should be on the alert for incursions of this virus.
Movement of virus within 18 months of 1st detection in southern Russia to the Korean Peninsula and Japan has also occurred on 2 occasions
(2006 and 2010).

Proactive surveillance and early reporting of these results by Russian scientists is an excellent demonstration of how surveillance is used as a tool for early warning. Note that as the virus may not necessarily be fatal for wild birds, the 1st evidence of infection may only be when spillover occurs into domestic poultry populations, especially galliformes, which are more likely to show signs of disease when infected.

Contributors: Les Sims, Sergei Khomenko, Akiko Kamata, Guillaume Belot, Jonathan Bastard, Elisa Palamara, Mirko Bruni, Sophie von Dobschuetz, Gwenaelle Dauphin, Eran Raizman, Juan Lubroth

VOL 35 — SEPTEMBER 2016 EMPRES-ANIMALHEALTH@FAO.ORG | WWW.FAO.ORG/AG/EMPRES.HTML

Zoonotic infections by avian influenza viruses occur at the human–poultry interface, but the modes of transmission have not been fully investigated. We assessed the potential for airborne and fomite transmission at live poultry markets in Guangzhou city and in Hong Kong Special Administrative Region (SAR), China, during 2014 and 2015. Viral genome and infectious avian influenza A viruses of H5N6, H7N9, and H9N2 subtypes were detected predominantly from particles larger or equal to 1 μm in diameter in the air sampled with cyclone-based bioaerosol samplers at the live poultry markets in Guangzhou. Influenza A(H9N2) viruses were ubiquitously isolated every month during the 2014 and 2015. Influenza A(H9N2) viruses were ubiquitously isolated every month during the study period from air and environmental swabs, and different lineages of H9N2 virus were isolated from markets where chickens and minor land-based poultry were sold. The use of de-feathering devices increased the quantity of virus-laden airborne particles while market closure reduced the amount of such particles. The results highlight the possibility of airborne transmission of avian influenza viruses among poultry or from poultry to humans within such settings. This may explain epidemiological observations in which some patients with H7N9 infection reported being in markets but no direct contact with live poultry or poultry stalls.

Zhou J, Wu J, Zeng X, Huang G, Zou L, Song Y, Gopinath D, Zhang X, Kang M, Lin J, Cowling BJ, Lindsley WG, Ke C, Peiris JSM, Yen H.

Euro Surveill. 2016;21(35):pii=30331. DOI: http://dx.doi. org/10.2807/1560-7917.ES.2016.21.35.30331

One of the major unresolved questions in influenza A virus (IAV) ecology is exemplified by the apparent disappearance of highly pathogenic (HP) H5N1, H5N2, and H5N8 (H5Nx) viruses containing the Eurasian hemagglutinin 2.3.4.4 clade from wild bird populations in North America. The introduction of Eurasian lineage HP H5 clade 2.3.4.4 H5N8 IAV and subsequent reassortment with low-pathogenic H?N2 and H?N1 North American wild bird-origin IAVs in late 2014 resulted in widespread HP H5Nx IAV infections and outbreaks in poultry and wild birds across two-thirds of North America starting in November 2014 and continuing through June 2015. Although the stamping out strategies adopted by the poultry industry and animal health authorities in Canada and the United States—which included culling, quarantining, increased biosecurity, and abstention from vaccine use—were successful in eradicating the HP H5Nx viruses from poultry, these activities do not explain the apparent disappearance of these viruses from migratory waterfowl. Here we examine current and historical aquatic bird IAV surveillance and outbreaks of HP H5Nx in poultry in the United States and Canada, providing additional evidence of unresolved mechanisms that restrict the emergence and perpetuation of HP avian influenza viruses in these natural reservoirs

Scott Kraussa, David E. Stallknechtb, Richard D. Slemonsc, Andrew S. Bowmanc, Rebecca L. Poulsonb, Jacqueline M. Noltingc, James P. Knowlesa, and Robert G. Webster

PNAS August 9, 2016 vol. 113 no. 32 9033-9038  doi: 10.1073/pnas.1608853113

Investigation into the Airborne Dissemination of H5N2 Highly Pathogenic Avian Influenza Virus During the 2015 Spring Outbreaks in the Midwestern United States.

We investigated the plausibility of aerosol transmission of H5N2 highly pathogenic avian influenza (HPAI) virus during the 2015 spring outbreaks that occurred in the U.S. midwest. Air samples were collected inside and outside of infected turkey and layer facilities. Samples were tested to assess HPAI virus concentration (RNA copies/m3 of air), virus viability, and virus distribution by particle size. HPAI virus RNA was detected inside and up to 1000 m from infected facilities. HPAI virus was isolated from air samples collected inside, immediately outside, up to 70 m from infected facilities, and in aerosol particles larger than 2.1 μm. Direct exposure to exhausted aerosols proved to be a significant source of environmental contamination. These findings demonstrate HPAI virus aerosolization from infected flocks, and that both the transport of infectious aerosolized particles and the deposition of particles on surfaces around infected premises represent a potential risk for the spread of HPAI.

Montserrat Torremorell, Carmen Alonso, Peter R. Davies, Peter C. Raynor, Devi Patnayak, Mia Torchetti, and Brian McCluskey (2016)

Avian Diseases: September 2016, Vol. 60, No. 3, pp. 637-643.

Campylobacter is the commonest bacterial cause of gastrointestinal infection in humans, and chicken meat is the major source of infection throughout the world. Strict and expensive on-farm biosecurity measures have been largely unsuccessful in controlling infection and are hampered by the time needed to analyse faecal samples, with the result that Campylobacter status is often known only after a flock has been processed. Our data demonstrate an alternative approach that monitors the behaviour of live chickens with cameras and analyses the ‘optical flow’ patterns made by flock movements. Campylobacter-free chicken flocks have higher mean and lower kurtosis of optical flow than those testing positive for Campylobacter by microbiological methods. We show that by monitoring behaviour in this way, flocks likely to become positive can be identified within the first 7–10 days of life, much earlier than conventional on-farm microbiological methods. This early warning has the potential to lead to a more targeted approach to Campylobacter control and also provides new insights into possible sources of infection that could transform the control of this globally important food-borne pathogen.

Colles FM, Cain RJ, Nickson T, Smith AL, Roberts SJ, Maiden MCJ, Lunn D,Dawkins MS.

Proc. R. Soc. B 283: 20152323. http://dx.doi.org/10.1098/rspb.2015.2323

The role and significance of wildlife–livestock interfaces in disease ecology has largely been neglected, despite recent interest in animals as origins of emerging diseases in humans. Scoping review methods were applied to objectively assess the relative interest by the scientific community in infectious diseases at interfaces between wildlife and livestock, to characterize animal species and regions involved, as well as to identify trends over time. An extensive literature search combining wildlife, livestock, disease, and geographical search terms yielded 78,861 publications, of which 15,998 were included in the analysis. Publications dated from 1912 to 2013 and showed a continuous increasing trend, including a shift from parasitic to viral diseases over time. In particular there was a significant increase in publications on the artiodactyls –cattle and bird–poultry interface after 2002 and 2003, respectively. These trends could be traced to key disease events that stimulated public interest and research funding. Among the top 10 diseases identified by this review, the majority were zoonoses. Prominent wildlife –livestock interfaces resulted largely from interaction between phylogenetically closely related and/or sympatric species. The bird–poultry interface was the most frequently cited wildlife –livestock interface worldwide with other interfaces reflecting regional circumstances. This review provides the most comprehensive overview of research on infectious diseases at the wildlife-livestock interface to date.

Anke K. Wiethoelter, Daniel Beltrán-Alcrudo, Richard Kock, and Siobhan M. Mora

PNAS| August 4, 2015 | vol. 112 | no. 31 www.pnas.org/cgi/doi/10.1073/pnas.1422741112

Background. Live animal markets have been implicated in transmission of influenza A viruses (IAVs) from animals to people. We sought to characterize IAVs at two live animal markets in Minnesota to assess potential routes of occupational exposure and risk for interspecies transmission.

Methods. We implemented surveillance for IAVs among employees, swine, and environment (air and surfaces) during a 12-week period (October 2012–January 2013) at two markets epidemiologically associated with persons with swine-origin IAV (variant) infections. Real-time reverse transcription polymerase chain reaction (rRT-PCR), viral culture, and whole genome sequencing were performed on respiratory and environmental specimens, and serology on sera from employees at beginning and end of surveillance.

Results. Nasal swabs from 11 (65%) of 17 employees tested positive for IAVs by rRT-PCR; seven employees tested positive on multiple occasions and one employee reported influenza-like illness. Eleven (73%) of 15 employees had baseline hemagglutination-inhibition antibody titers ≥40 to swine-origin IAVs, but only one demonstrated a 4-fold titer increase to both swine-origin, and pandemic A/Mexico/4108/2009 IAVs. IAVs were isolated from swine (72/84), air (30/45) and pen railings (5/21). Whole genome sequencing of 122 IAVs isolated from swine and environmental specimens revealed multiple strains and subtype codetections. Multiple gene segment exchanges among and within subtypes were observed, resulting in new genetic constellations and reassortant viruses. Genetic sequence similarities of 99%–100% among IAVs of one market customer and swine indicated interspecies transmission.

Conclusions. At markets where swine and persons are in close contact, swine-origin IAVs are prevalent and potentially provide conditions for novel IAV emergence

Mary J. Choi, Montserrat Torremorell, Jeff B. Bender et al.

Clin Infect Dis. (2015) doi: 10.1093/cid/civ618

Background/purpose: We conducted a case series study to review the epidemiology of human influenza A(H7N9) infection reported in Hong Kong.

Methods: We reviewed case records of confirmed human cases of influenza A(H7N9) infection reported in Hong Kong in the 2013-2014 winter season. We compared the median viral shedding duration and interval from illness onset to initiation of oseltamivir treatment between severe and mild cases. We estimated the incubation period of influenza A(H7N9) virus from cases with a single known date of poultry exposure.

Results: A total of 10 cases were reported and all were imported infection from Mainland China. 4 patients died and the cause of death was related to influenza A(H7N9) infection in 2 patients. The median interval from illness onset to initiation of oseltamivir treatment for the severe cases (4.5 days) was significantly longer than the mild cases (2 days; p = 0.025). Severe cases had a significantly longer viral shedding duration than mild cases (p = 0.028). The median incubation period for cases with a single known exposure date was 4 days. Nasopharyngeal aspirate taken from the 88 close contacts of the 10 patients all tested negative for influenza A virus using reverse transcription polymerase chain reaction.

Conclusion: Delayed administration of antiviral treatment may be associated with a more severe illness for influenza A(H7N9) infection. Despite our aggressive contact tracing policy with laboratory testing of all close contacts, no secondary case was identified, which implied that the potential of human-to-human transmission of the circulating influenza A(H7N9) virus remains low.

Leung YH, To MK, Lam TS, et al

J Microbiol Immunol Infect. 2015 Jun 30. pii: S1684-1182(15)00772-0. doi: 10.1016/j.jmii.2015.06.004]

Abstract.
Newly emerged highly pathogenic avian influenza (HPAI) A H5 viruses have caused outbreaks among birds in the United States. These viruses differ genetically from HPAI H5 viruses that previously caused human illness, most notably in Asia and Africa. To assess the risk for animal-to-human HPAI H5 virus transmission in the United States, we determined the number of persons with self-reported exposure to infected birds, the number with an acute respiratory infection (ARI) during a 10-day postexposure period, and the number with ARI who tested positive for influenza by real-time reverse transcription PCR or serologic testing for each outbreak during 15 Dec 2014-31 Mar 2015. During 60 outbreaks in 13 states, a total of 164 persons were exposed to infected birds. ARI developed in 5 of these persons within 10 days of exposure. H5 influenza virus infection was not identified in any persons with ARI, suggesting a low risk for animal-to-human HPAI H5 virus transmission.

Arriola CS, Nelson DI, Deliberto TJ, et al.

Source: Emerg Infect Dis. 2015 21 (12)-Dec 2015 [edited]

A regular update on the main disease threats monitored and analysed by the FAO/AGAH/GLEWS worldwide. This intelligence report contains relevant analysis of disease information collected by FAO GLEWS from official and informal sources and prepared with the kind support of donors to enhance global early warning and surveillance for animal diseases. The global disease intelligence report highlights also a description of possible drivers of animal diseases incursion or spread and forecasts risk of animal diseases based on risk assessment activities conducted by the animal health service for different health threats

Year of publication: 2015
Publisher: FAO
Pages: 16 p.
Job Number: I4774
Office: Agriculture and Consumer Protection
Corporate author: Animal Production and Health Division

Phylogenetic analysis of highly pathogenic avian influenza A(H5N8) virus strains causing outbreaks in Dutch poultry farms in 2014 provides evidence for separate introduction of the virus in four outbreaks in farms located 16–112 km from each other and for between-farm transmission between the third and fourth outbreak in farms located 550 m from each other. In addition, the analysis showed that all European and two Japanese H5N8 virus strains are very closely related and seem to originate from a calculated common ancestor, which arose between July and September 2014. Our findings suggest that the Dutch outbreak virus strain ‘Ter Aar’ and the first German outbreak strain from 2014 shared a common ancestor. In addition, the data indicate that the Dutch outbreak viruses descended from an H5N8 virus that circulated around 2009 in Asia, possibly China, and subsequently spread to South Korea and Japan and finally also to Europe. Evolution of the virus seemed to follow a parallel track in Japan and Europe, which supports the hypothesis that H5N8 virus was exchanged between migratory wild waterfowl at their breeding grounds in Siberia and from there was carried by migrating waterfowl to Europe.

R J Bouwstra, G Koch, R Heutink, F Harders, A van der Spek, A R Elbers, A Bossers

Eurosurveillance, Volume 20, Issue 26, 02 July 2015Surveillance and outbreak reports

The aim of this study was to design and implement a seroprevalence map based on business intelligence for low pathogenicity notifiable avian influenza (LPNAI) in broiler chickens in Comunidad Valenciana (Spain). The software mapping tool developed for this study consisted of three main phases: data collection, data analysis and data representation. To obtain the serological data, the authors analysed 8,520 serum samples from broiler farms over three years. The data were represented on a map of Comunidad Valenciana, including geographical information of flock locations to facilitate disease monitoring. No clinical signs of LPNAI were reported in the studied flocks. The data from this study showed no evidence of contact with LPNAI in broiler flocks and the novel software mapping tool proved a valuable method for easily monitoring the serological response to avian influenza, including geographical information.

C. García, J.M. Soriano, P. Catalá-Gregori

Rev. sci. tech. Off. int. Epiz., 2014, 33 (3), ...No. 10102014-00046-EN 1/15

Ozawa M, Matsuu A, Tokorozaki K, Horie M, Masatani T, Nakagawa H, Okuya K, Kawabata T, Toda S.

We isolated eight highly pathogenic H5N8 avian influenza viruses (H5N8 HPAIVs) in the 2014/15 winter season at an overwintering site of migratory birds in Japan. Genetic analyses revealed that these isolates were divided into three groups, indicating the co-circulation of three genetic groups of H5N8 HPAIV among these migratory birds. These results also imply the possibility of global redistribution of the H5N8 HPAIVs via the migration of these birds next winter

Euro Surveill. 2015;20(20):pii=21132. Available online: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=21132

Although only one case of H6 virus infection in a human has been reported worldwide (6), several biological characteristics of H6 viruses indicate that they are highly infectious to mammals. Approximately 34 percent of H6 viruses circulating in China have enhanced affinity to human-like receptors (alpha-2,6 NeuAcGal) (2). H6 viruses can also infect mice without prior adaptation (2,7), and some H6 viruses can be transmitted efficiently among guinea pigs (2). To evaluate the potential threat of H6 viruses to human health, we conducted a systematic serologic study in populations occupationally exposed to H6 viruses. Human infection with influenza H6 virus in Mainland China has not been reported, but 63 serum specimens tested in our study were positive for the H6 virus. This level of seropositivity is much higher than that for highly pathogenic avian influenza A(H5N1) virus, for which only 2 of the serum specimens we tested were positive (data not shown), but much lower than the seropositivity level for low pathogenicity avian influenza A(H9N2) virus; 3.4 percent of the samples tested were positive for A/Chicken/Hong Kong/G9/1997(H9N2)-like virus (data not shown). A previous US study has reported H6N2-positive antibodies in veterinarians (9). Our results and the veterinarian study indicate that the H6N2 virus could infect humans. In our study, positive samples were detected in 19 of 22 provinces and in all tested worker populations, suggesting that the H6 virus has been broadly circulating in birds in China. Live poultry market exposure is the major risk factor for human infection with avian influenza H6 virus. The limitation of this study is that antigen selection may not accurately detect neutralization antibodies for different subtypes of H6 viruses. Surveillance of the H6 virus in birds and occupationally exposed populations should be strengthened for pandemic preparedness.

Xin L, Bai T, Zhou JF, et al.

2015. _Emerg Infect Dis_ 21(7) Jul [date cited]. DOI: 10.3201/eid2107.150135. Letter. Ahead of print

Human infection with avian influenza A(H7N9) virus is associated mainly with the exposure to infected poultry. The factors that allow interspecies transmission but limit human-to-human transmission are unknown. Here we show that A/Anhui/1/2013(H7N9) influenza virus infection of chickens (natural hosts) is asymptomatic and that it generates a high genetic diversity. In contrast, diversity is tightly restricted in infected ferrets, limiting further adaptation to a fully transmissible form. Airborne transmission in ferrets is accompanied by the mutations in PB1, NP and NA genes that reduce viral polymerase and neuraminidase activity. Therefore, while A(H7N9) virus can infect mammals, further adaptation appears to incur a fitness cost. Our results reveal that a tight genetic bottleneck during avian-to-mammalian transmission is a limiting factor in A(H7N9) influenza virus adaptation to mammals. This previously unrecognized biological mechanism limiting species jumps provides a measure of adaptive potential and may serve as a risk assessment tool for pandemic preparedness.

Hassan Zaraket, Tatiana Baranovich, Bryan S. Kaplan, Robert Carter, Min-Suk Song, James C. Paulson, Jerold E. Rehg, Justin Bahl, Jeri C. Crumpton, Jon Seiler, Michael Edmonson, Gang Wu, Erik Karlsson, Thomas Fabrizio, Huachen Zhu, Yi Guan, Matloob Husain, Stacey Schultz-Cherry, Scott Krauss, Ryan McBride, Robert G. Webster, Elena A. Govorkova, Jinghui Zhang, Charles J. Russell, & Richard J. Webby

Nature CommunicationsVolume:6,Article number:6553DOI:doi:10.1038/ncomms7553

We report an outbreak of Salmonella Enteritidis phage type 14b (PT14b) in the United Kingdom (UK) between May and September 2014 where Public Health England launched an investigation to identify the source of infection and implement control measures. During the same period, outbreaks caused by a Salmonella Enteritidis strain with a specific multilocus variable-number tandem repeat analysis (MLVA) profile occurred in other European Union Member States. Isolates from a number of persons affected by the UK outbreak, who had initially been tested by MLVA also shared this particular profile. Cases were defined as any person infected with S. Enteritidis PT14b, resident in England or Wales and without history of travel outside of this geographical area during the incubation period, reported from 1 June 2014 onwards, with a MLVA profile of 2–11–9-7–4-3–2-8–9 or a single locus variant thereof. In total, 287 cases met the definition. Food traceback investigations in the UK and other affected European countries linked the outbreaks to chicken eggs from a German company. We undertook whole genome sequencing of isolates from UK and European cases, implicated UK premises, and German eggs: isolates were highly similar. Combined with food traceback information, this confirmed that the UK outbreak was also linked to a German producer.

T Inns, C Lane, T Peters, T Dallma2, C Chatt, N McFarland, P Crook, T Bishop, J Edge, J Hawker, R Elson, K Neal, G K Adak, P Cleary

Eurosurveillance, Volume 20, Issue 16, 23 April 2015

The spatial spread of the highly pathogenic avian influenza virus H5N1 and its long-term persistence in Asia have resulted in avian influenza panzootics and enormous economic losses in the poultry sector. However, an understanding of the regional long-distance transmission and seasonal patterns of the virus is still lacking. In this study, we present a phylogeographic approach to reconstruct the viral migration network. We show that within each wild fowl migratory flyway, the timing of H5N1 outbreaks and viral migrations are closely associated, but little viral transmission was observed between the flyways. The bird migration network is shown to better reflect the observed viral gene sequence data than other networks and contributes to seasonal H5N1 epidemics in local regions and its large-scale transmission along flyways. These findings have potentially far-reaching consequences, improving our understanding of how bird migration drives the periodic reemergence of H5N1 in Asia. 

Huaiyu Tiana, Sen Zhoub, Lu Dongc, Thomas P. Van Boeckeld, Yujun Cuie, Yarong Wue, Bernard Cazelles, Shanqian Huang, Ruifu Yang, Bryan T. Grenfelld and Bing Xua 

Proceedings of the National Academy of Sciences of the United States of America PNAS, vol. 112 no. 1 > Huaiyu Tian, 172–177doi: 10.1073/pnas.1405216112

An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. The aim of this study was to evaluate the pathogenesis in and mode of transmission of this virus among domestic and wild ducks. Three of the viruses had similar pathogenicity among infected domestic ducks: the H5N8 viruses were moderately pathogenic (0%–20% mortality rate); in wild mallard ducks, the H5N8 and H5N1 viruses did not cause severe illness or death; viral replication and shedding were greater in H5N8-infected mallards than in H5N1-infected mallards. Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. We propose active surveillance to support prevention of spread of the virus, and in areas where infection is documented, culling of wild birds and infected poultry, especially domestic ducks.

Kang HM, Lee EK, Song BM, Jeong J, Choi JG, et al. 

Emerg Infect Dis. 2015 Feb [date cited].

A survey of national animal influenza surveillance programmes was conducted to assess the current capacity to detect influenza viruses with zoonotic potential in animals (i.e. those influenza viruses that can be naturally transmitted between animals and humans) at regional and global levels. Information on 587 animal influenza surveillance system components was collected for 99 countries from Chief Veterinary Officers (CVOs) (n = 94) and published literature. Less than 1% (n = 4) of these components were specifically aimed at detecting influenza viruses with pandemic potential in animals (i.e. those influenza viruses that are capable of causing epidemic spread in human populations over large geographical regions or worldwide), which would have zoonotic potential as a prerequisite. Those countries that sought to detect influenza viruses with pandemic potential searched for such viruses exclusively in domestic pigs. This work shows the global need for increasing surveillance that targets potentially zoonotic influenza viruses in relevant animal species.

S. VON DOBSCHUETZ, M. DE NARDI, K. A. HARRIS, O. MUNOZ, A. C. BREED, B. WIELAND, G. DAUPHIN, J. LUBROTH, K. D. C. STÄRK and the FLURISK Consortium

Epidemiol. Infect., Page 1 of 18. © Food and Agriculture Organization of the United Nations 2014 doi:10.1017/S0950268814002106

European quail (Coturnix c. coturnix) may share with Japanese quail (Coturnix c. japonica) its potential as an intermediate host and reservoir of avian influenza viruses (AIV). To elucidate this question, European quail were experimentally challenged with two highly pathogenic AIV (HPAIV) (H7N1/HP and H5N1/HP) and one low pathogenic AIV (LPAIV) (H7N2/LP). Contact animals were also used to assess the viral transmission among birds. Severe neurological signs and mortality rates of 67% (H7N1/HP) and 92% (H5N1/HP) were observed. Although histopathological findings were present in both HPAIV-infected groups, H5N1/HP-quail displayed a broader viral antigen distribution and extent of microscopic lesions. Neither clinical nor pathological involvement was observed in LPAIV-infected quail. Consistent long-term viral shedding and effective transmission to naive quail was demonstrated for the three studied AIV. Drinking water arose as a possible transmission route and feathers as a potential origin of HPAIV dissemination. The present study demonstrates that European quail may play a major role in AI epidemiology, highlighting the need to further understand its putative role as an intermediate host for avian/mammalian reassortant viruses.

Kateri Bertran, Roser Dolz, Núria Busquets, Virginia Gamino, Júlia Vergara-Alert, Aida J Chaves, Antonio Ramis, Xavier F Abad, Ursula Höfle, Natália Majó 

Veterinary Research 2013, 44:23 (28 March 2013)

Pet birds are a not-so-well known veterinarian’s clientship fraction. Bought individually or in couples, as families often do (which is a lucrative business for pet shops or local breeders) or traded (sometimes illegally) for their very high genetic or exotic value, these birds, commonly canaries, parakeets or parrots, are regularly sold at high prices. These animals, however, are potential carriers and/or transmitters of zoonotic diseases. Some of them could have an important impact on human health, like chlamydophilosis, salmonellosis or even highly pathogenic avian influenza A H5N1. This review paper, although non exhaustive, aims at enlightening, by the description of several cases of bird-human transmission, the risks encountered by bird owners, including children. Public health consequences will be discussed and emphasis will be made on some vector-borne diseases, known to be emergent or which are underestimated, like those transmitted by the red mite Dermanyssus gallinae. Finally, biosecurity and hygiene, as well as prevention guidelines will be developed and perspectives proposed.

Geraldine Boseret, Bertrand Losson, Jacques G Mainil, Etienne Thiry, Claude Saegerman

Veterinary Research 2013, 44:36 (20 May 2013)

Keiko Herrick and colleagues used machine-learning algorithms and data mining to form a predictive ecological model of Avian Influenza Virus in wild bird populations, identifying specific northern regions at high risk of outbreak.

Keiko A Herrick, Falk Huettmann and Michael A Lindgren 

Veterinary Research 2013, 44:42 doi:10.1186/1297-9716-44-42

Geraldine Boseret and colleagues address the biosecurity and hygiene concerns of human contact with pet birds, describing the risk of zoonotic infection with salmonellosis, avian influenza A H5N1 and other diseases.

Geraldine Boseret, Bertrand Losson, Jacques G Mainil3, Etienne Thiry and Claude Saegerman

Veterinary Research 2013, 44:36 doi:10.1186/1297-9716-44-36

A more rigorous and nuanced understanding of land-use change (LUC) as a driver of emerging infectious disease (EID) is required. Here we examine post hunter-gatherer LUC as a driver of infectious disease in one biogeographical region with a compressed and documented history—continental Australia. We do this by examining land-use and native vegetation change (LUCC) associations with infectious disease emergence identified through a systematic (1973–2010) and historical (1788–1973) review of infectious disease literature of humans and animals. We find that 22% (20) of the systematically reviewed EIDs are associated with LUCC, most frequently where natural landscapes have been removed or replaced with agriculture, plantations, livestock or urban development. Historical clustering of vector-borne, zoonotic and environmental disease emergence also follows major periods of extensive land clearing. These advanced stages of LUCC are accompanied by changes in the distribution and density of hosts and vectors, at varying scales and chronology. This review of infectious disease emergence in one continent provides valuable insight into the association between accelerated global LUC and concurrent accelerated infectious disease emergence.

Rosemary A. McFarlane, Adrian C. Sleighand Anthony J. McMichael

Int. J. Environ. Res. Public Health 2013, 10(7), 2699-2719; doi:10.3390/ijerph10072699

Influenza A H10N7 virus with a hemagglutinin gene of North American origin was detected in Australian chickens and poultry abattoir workers in New South Wales in 2010 and in chickens in Queensland on a mixed chicken and domestic duck farm in 2012. We investigated their genomic origins by sequencing full and partial genomes of H10 viruses isolated from wild aquatic birds and poultry in Australia and analysed them with all available avian influenza virus sequences from Oceania and representative viruses from North America and Eurasia. Our analysis showed that the H10N7 viruses isolated from poultry were similar to those circulating since 2009 in Australian aquatic birds; and their initial transmission into Australia occurred during 2007—2008. The H10 viruses that appear to have developed endemicity in Australian wild aquatic birds, were derived from several viruses circulating in waterfowl along various flyways. Their hemagglutinin gene was derived from aquatic birds in the western states of the USA, whereas the neuraminidase was closely related to viruses previously detected in waterfowl in Japan. The remaining genes were derived from Eurasian avian influenza lineages. Our analysis of virological data spanning 40 years in Oceania indicates that the long-term evolutionary dynamics of avian influenza viruses in Australia may be determined by climatic changes. The introduction and long-term persistence of avian influenza virus lineages were observed during periods with increased rainfall, whereas bottlenecks and extinction was observed during phases of widespread decreases in rainfall. These results extend our understanding of factors affecting the dynamics of avian influenza and provide important considerations for surveillance and disease control strategies.

Dhanasekaran Vijaykrishna, Yi-Mo Deng, Yvonne C. F. Su, Mathieu Fourment, Pina Iannello, George G. Arzey, Philip M. Hansbro, K. Edla Arzey, Peter D. Kirkland, Simone Warner, Kim O’Riley, Ian G. Barr, Gavin J. D. Smith and Aeron C. Hurt

Journal of Virology Published ahead of print 17 July 2013, doi: 10.1128/JVI.03437-12 JVI.03437-12

During 2005–2010, the Canadian Integrated Program for Antimicrobial Resistance Surveillance identified increased prevalence of ciprofloxacin (a fluoroquinolone) resistance among Campylobacter isolates from retail chicken in British Columbia (4%–17%) and Saskatchewan (6%–11%), Canada. Fluoroquinolones are critically important to human medicine and are not labeled for use in poultry in Canada.

Agnes Agunos , David Léger, Brent P. Avery, E. Jane Parmley, Anne Deckert, Carolee A. Carson, and Lucie Dutil

Emerg Infect Dis [Internet]. 2013 Jul [date cited].

Exotic and emerging viral pathogens associated with high morbidity and mortality in humans are being identified annually with recent examples including Lujo virus in southern Africa, Severe Fever with Thrombocytopenia Syndrome virus in China and a SARS-like coronavirus in the Middle East. The sporadic nature of these infections hampers our understanding of these diseases and limits the opportunities to design appropriate medical countermeasures against them. Because of this, animal models are utilized to gain insight into the pathogenesis of disease with the overall goal of identifying potential targets for intervention and evaluating specific therapeutics and vaccines. For these reasons it is imperative that animal models of disease recapitulate the human condition as closely as possible in order to provide the best predictive data with respect to the potential efficacy in humans. In this article we review the current status of disease models for highly pathogenic and emerging viral pathogens.

David Safronetz1,

Current Opinion in Virology
Volume 3, Issue 2, April 2013, Pages 205–209

Free-living wild birds worldwide act as reservoir for Chlamydia psittaci, but the risk of transmission to humans through contact with wild birds has not been widely documented. From 12 January to April 9 2013, a total of 25 cases of psittacosis were detected in southern Sweden, about a threefold increase compared with the mean of the previous 10 years. A matched case–control study investigating both domestic and wild bird exposure showed that cases were more likely than controls to have cleaned wild bird feeders or been exposed to wild bird droppings in other ways (OR: 10.1; 95% CI: 2.1–47.9). We recommend precautionary measures such as wetting bird feeders before cleaning them, to reduce the risk of transmission of C. psittaci when in contact with bird droppings. Furthermore, C. psittaci should be considered for inclusion in laboratory diagnostic routines when analysing samples from patients with atypical pneumonia, since our findings suggest that psittacosis is underdiagnosed.

M Rehn1,2, H Ringberg3, A Runehagen4, B Herrmann5, B Olsen6, A C Petersson7, M Hjertqvist1, S Kühlmann-Berenzon1, A Wallensten1

Euro Surveill. 2013;18(19):pii=20478

As of 10 April 2013, 33 human cases infected with a novel influenza A(H7N9) virus have been laboratory confirmed in Shanghai, Anhui, Jiangsu and Zhejiang provinces in China (Figure1). This case count came after on 31 March 2013, the Chinese authorities had announced the identification of a novel influenza A virus, an A(H7H9) virus, in three people in Shanghai and Anhui province. Two men in Shanghai, 87 and 27 years old, respectively, had become ill with influenza-like (ILI) symptoms and progressed to severe lower respiratory tract infections within a week in mid to late February, and died from acute respiratory distress syndrome hereafter [1,2]. The two had no epidemiological link and no known exposure to evidently sick animals. One of them was a pork butcher. The third case was a 35-year-old woman from Anhui province, adjacent to Shanghai, who also became ill with ILI with symptom onset on 9 March followed by severe respiratory disease and death.

A Nicoll, N Danielsson

Eurosurveillance, Volume 18, Issue 15, 11 April 2013

Studies have suggested that flies play a linking role in the epidemiology of Campylobacter spp. in broiler chickens and that fly screens can reduce the prevalence of Campylobacter spp. We examined the year-round and long-term effects of fly screens in 10 broiler chicken houses (99 flocks) in Denmark. Prevalence of Campylobacter spp.–positive flocks was significantly reduced, from 41.4% during 2003–2005 (before fly screens) to 10.3% in 2006–2009 (with fly screens). In fly screen houses, Campylobacter spp. prevalence did not peak during the summer. Nationally, prevalence of Campylobacter spp.–positive flocks in Denmark could have been reduced by an estimated 77% during summer had fly screens been part of biosecurity practices. These results imply that fly screens might help reduce prevalence of campylobacteriosis among humans, which is closely linked to Campylobacter spp. prevalence among broiler chicken flocks.


Bahrndorff S, Rangstrup-Christensen L, Nordentoft S, Hald B.

Emerg Infect Dis [Internet]. Volume 19, Number 3—March 2013 DOI: 10.3201/eid1903.111593

Crimean-Congo hemorrhagic fever virus was detected in ticks removed from migratory birds in Morocco. This finding demonstrates the circulation of this virus in northwestern Africa and supports the hypothesis that the virus can be introduced into Europe by infected ticks transported from Africa by migratory birds.


Ana M. Palomar, Aránzazu Portillo, Paula Santibáñez, David Mazuelas, Juan Arizaga, Ariñe Crespo, Óscar Gutiérrez, Juan Francisco Cuadrado, and José A. Oteo

Emerg Infect Dis [Internet] Volume 19, Number 2—February 2013. DOI: 10.3201/eid1902.121193

Theory predicts that selection for pathogen virulence and horizontal transmission is highest at the onset of an epidemic but decreases thereafter, as the epidemic depletes the pool of susceptible hosts. We tested this prediction by tracking the competition between the latent bacteriophage λ and its virulent mutant λcI857 throughout experimental epidemics taking place in continuous cultures of Escherichia coli. As expected, the virulent λcI857 is strongly favored in the early stage of the epidemic, but loses competition with the latent virus as prevalence increases. We show that the observed transient selection for virulence and horizontal transmission can be fully explained within the framework of evolutionary epidemiology theory. This experimental validation of our predictions is a key step towards a predictive theory for the evolution of virulence in emerging infectious diseases.

Thomas W. Berngruber, Rémy Froissart, Sylvain Gandon

PLoS Pathog 9(3): e1003209. doi:10.1371/journal.ppat.1003209

Campylobacteriosis; QMRA; poultry; carcass; control measures

Danish organic broiler meat, represented by carcasses sampled at the end of processing after chilling, was more frequently contaminated with thermotolerant Campylobacter spp. than conventional broiler carcasses; the yearly mean prevalence being 54.2% (CI: 40.9-67.5) for organic and 19.7% (CI: 14.8-24.7) for conventional carcasses. Campylobacter jejuni was the most frequently isolated species. The difference in prevalence was obvious in all quarters of the year. Contamination of organic and conventional broiler carcasses was more likely to occur in the warmer summer months, in this case in the third quarter, as also documented for conventional broiler flocks. When contaminated, the mean concentration of Campylobacter on neck skin samples of organic and conventional carcasses was not significantly different (P = 0.428); 2.0 ± 0.65 log10 cfu per g and 2.1 ± 0.93 log10 cfu per g, respectively. Assessing the relative risk of becoming ill following exposure to Campylobacter on conventional or organic broiler meat indicated that the risk per serving from organic carcasses was 1.7 times higher than that of conventional carcasses. The higher risk of illness from organic broiler carcasses compared with conventional broiler carcasses emphasizes the importance of implementing control measures in organic broiler production.

Hanne Rosenquist, Louise Boysen, Anne Louise Krogh, Annette Nygaard Jensen, Maarten Nauta

International Journal of Food Microbiology
Available online 1 February 2013

Outbreaks of highly pathogenic avian influenza in poultry can cause severe economic damage and represent a public health threat. Development of efficient containment measures requires an understanding of how these influenza viruses are transmitted from one farm to the next. However, the actual mechanisms of inter-farm transmission are largely unknown. Dispersal of infectious material by wind has been suggested but never demonstrated as a possible cause of transmission between farms. Here, we provide statistical evidence that the direction of spread of avian influenza A(H7N7) is correlated with the direction of wind at date of infection. We find the direction of spread by reconstructing the transmission tree for a large outbreak in the Netherlands in 2003 using detailed genetic and epidemiological data. We conservatively estimate the contribution of a possible wind-mediated mechanism to the total amount of spread during this outbreak to be around 18 percent.

Ypma RJ, Jonges M, Bataille A, Stegeman A, Koch G, van Boven M, Koopmans M, van Ballegooijen WM, Wallinga J.

Journal of Infectious Diseases 2012, Advance Access; published 10 Dec 2012 

Bioconcentration—Clams—Influenza virus.

We report experimental evidence for bioconcentration of a low-pathogenicity avian influenza virus (H6N8) in the tissue of freshwater clams. Our results support the concept that freshwater clams may provide an effective tool for use in the early detection of influenza A viruses in aquatic environments.

Kathryn P. Huyvaert, Jenny S. Carlson, Kevin T. Bentler, Kacy R. Cobble, Dale L. Nolte, and Alan B. Franklin.

Vector-Borne and Zoonotic Diseases. October 2012, 12(10): 904-906. doi:10.1089/vbz.2012.0993.

Adamantanes;antiviral resistance;avian influenza virus;live bird markets;matrix gene;wild birds

Background Wild birds are the natural hosts for influenza A viruses (IAVs) and provide a niche for the maintenance of this virus.
Objectives This study was undertaken to analyze nucleotide sequences of the matrix (M) gene of AIVs isolated from wild birds and live bird markets (LBMs) to index the changes occurring in this gene.
Methods M-gene of 229 avian influenza virus (AIV) isolates obtained from wild birds and LBMs was amplified and sequenced. Full-length sequences (∼900 nt.) thus obtained were analyzed to identify changes that may be associated with resistance to adamantanes. Phylogenetic analysis of all sequences was performed using clustalw, and evolutionary distances were calculated by maximum composite likelihood method using mega (ver. 5.0) software.
Results Twenty-seven different viral subtypes were represented with H3N8 being the most dominant subtype in wild birds and H7N2 being the predominant subtype among isolates from LBMs. Phylogenetic analysis of the M-gene showed a high degree of nucleotide sequence identity with US isolates of AIVs but not with those of Asian or European lineages. While none of the isolates from wild birds had any antiviral resistance–associated mutations, 17 LBM isolates carried polymorphisms known to cause reduced susceptibility to antiviral drugs (adamantanes). Of these 17 isolates, 16 had S31N change and one isolate had V27A mutation.
Conclusions These results indicate independent evolution of M-gene in the absence of any antiviral drugs leading to mutations causing resistance indicating the need for continued active surveillance of AIVs.

Yogesh Chander, Naresh Jindal, Srinand Sreevatsan, David E. Stallknecht, Sagar M. Goyal

Influenza and Other Respiratory Viruses DOI: 10.1111/irv.12003

On March 15, 2010, a highly pathogenic avian influenza virus was isolated from the carcass of a common buzzard (Buteo buteo) in Bulgaria. Phylogenetic analyses of the virus showed a close genetic relationship with influenza virus A (H5N1) clade 2.3.2.1 viruses isolated from wild birds in the Tyva Republic and Mongolia during 2009–2010. Designated A/common buzzard/Bulgaria/38WB/2010, this strain was highly pathogenic in chickens but had low pathogenicity in mice and ferrets and no molecular markers of increased pathogenicity in mammals. The establishment of clade 2.3.2.1 highly pathogenic avian influenza viruses of the H5N1 subtype in wild birds in Europe would increase the likelihood of health threats to humans and poultry in the region.

Atanaska Marinova-Petkova, Georgi Georgiev, Patrick Seiler, Daniel Darnell, John Franks, Scott Krauss, Richard J. Webby, and Robert G. Webster

Emerg Infect Dis [Internet]. 2012 Oct [date cited].

Epidemiology; surveillance; veterinary epidemiology; West Nile virus; zoonoses

West Nile virus (WNV) is a zoonotic arthropod-borne pathogen with continued geographical expansion in Europe. We present and evaluate data on the temporal, spatial and bird species focus of the WNV surveillance programme in dead wild birds in Great Britain (2002–2009). During this period all bird samples tested negative for WNV. Eighty-two per cent of the 2072 submissions occurred during the peak period of vector activity with 53% tested during April–July before human and equine infection would be expected. Samples were received from every county, but there was significant geographical clustering (nearest neighbour index=0·23, P<0·001). Over 240 species were represented, with surveillance more likely to detect WNV in resident bird species (92% of submissions) than migrants (8%). Evidence indicates that widespread avian mortality is not generally a reported feature of WNV in Europe and hence additional activities other than dead bird surveillance may maximize the ability to detect WNV circulation before the onset of human and equine infections.

V. A. BRUGMAN, D. L. HORTON, L. P. PHIPPS, N. JOHNSON, A. J. C. COOK, A. R. FOOKS and A. C. BREED

Epidemiology and Infection, Available on CJO2012 doi:10.1017/S095026881200177X

Since 2008, a progressive pneumonia has become prevalent in broilers and laying hens. This disease occurrs the first day after hatching and lasts more than 30 days, resulting in approximately 70% morbidity and 30% mortality in broilers. The objective of this study was to isolate and identify the pathogens that are responsible for the progressive pneumonia and establish an animal model for drug screening. 193 serum samples were collected from 8 intensive farms from 5 provinces in China and analysed in the current research. Our clinical survey showed that 65.2% to 100% of breeding broilers, breeding layers, broilers and laying hens were seropositive for ORT antibodies. From 8 intensive farms, six ORT isolates were identified by PCR and biochemical assays, and two H9N2 viruses were isolated. Newcastle Disease Virus (NDV) and Infectious Bronchitis Virus (IBV) were excluded. Typical pneumonia and airsacculitis were observed both in broilers inoculated intraperitoneally with an ORT isolate alone and in those co-infected with ORT and H9N2 virus isolates. Specifically,the survival rate was 30%, 20%, 70%, 50% and 90% in birds inoculated with ORT+H9N2 virus, ORT followed by
H9N2 virus, H9N2 virus followed by ORT, and ORT or H9N2 virus alone, respectively. The results of this study suggest that ORT infections of domestic poultry have been occurring frequently in China. ORT infection can induce higher economic losses and mortality if H9N2 AIV is also present. Although the isolation of ORT and H9N2 virus has been reported previously, there have been no reported co-infections of poultry with these two pathogens. This is the first report of co-infection of broilers with ORT and H9N2 virus, and this co-infection is probably associated with the outbreak of broiler airsacculitis in China, which has caused extensive economic losses.

Qing Pan, Aijing Liu, Faming Zhang, Yong Ling1, Changbo Ou, Na Hou and Cheng He

BMC Veterinary Research 2012, 8:104

We previously described how retail meat, particularly chicken, might be a reservoir for extraintestinal pathogenic Escherichia coli (ExPEC) causing urinary tract infections (UTIs) in humans. To rule out retail beef and pork as potential reservoirs, we tested 320 additional E. coli isolates from these meats. Isolates from beef and pork were significantly less likely than those from chicken to be genetically related to isolates from humans with UTIs. We then tested whether the reservoir for ExPEC in humans could be food animals themselves by comparing geographically and temporally matched E. coli isolates from 475 humans with UTIs and from cecal contents of 349 slaughtered animals. We found genetic similarities between E. coli from animals in abattoirs, principally chickens, and ExPEC causing UTIs in humans. ExPEC transmission from food animals could be responsible for human infections, and chickens are the most probable reservoir

Catherine Racicot Bergeron, Catharine Prussing1, Patrick Boerlin, Danielle Daignault, Lucie Dutil2, Richard J. Reid-Smith, George G. Zhanel, and Amee R. Manges

Emerg Infect Dis [serial on the Internet] 2012 Mar [date cited].

We amplified gene sequences from Anaplasma phagocytophilum, Borrelia garinii, B. valaisiana, B. turdi, Rickettsia monacensis, R. helvetica, R. sibirica sibirica, and Rickettsia spp. (including Candidatus Rickettsia vini) in ticks removed from birds in Spain. The findings support the role of passerine birds as possible dispersers of these tick-borne pathogens.


Ana M. Palomar, Paula Santibáñez, David Mazuelas, Lidia Roncero, Sonia Santibáñez, Aránzazu Portillo, and José A. Oteo

Emerg Infect Dis [serial on the Internet] 2012 Jul [date cited].

Transmission of influenza (H5N1) virus from birds to humans is a serious public health threat. In South Korea, serologic investigation among 2,512 poultry workers exposed during December 2003–March 2004 to poultry with confirmed or suspected influenza (H5N1) virus infection found antibodies in 9. Frequency of bird-to-human transmission was low.


Donghyok Kwon, Joo-Yeon Lee, Wooyoung Choi, Jang-Hoon Choi, Yoon-Seok Chung, Nam-Joo Lee, Hyang-Min Cheong, Jacqueline M. Katz, Hee-Bok Oh, Haewol Cho, and Chun Kang

Emerg Infect Dis [serial on the Internet]. 2012 Jun [date cited]. DOI: 10.3201/eid1806.111631

Avian influenza (AI) H9N2 has been reported from poultry in India. A seroepidemiological study was undertaken among poultry workers to understand the prevalence of antibodies against AI H9N2 in Pune, Maharashtra, India. A total of 338 poultry workers were sampled. Serum samples were tested for presence of antibodies against AI H9N2 virus by hemagglutination inhibition (HI) and microneutralization (MN) assays. A total of 249 baseline sera from general population from Pune were tested for antibodies against AI H9N2 and were negative by HI assay using ≥40 cut-off antibody titre. Overall 21 subjects (21/338 = 6.2%) were positive for antibodies against AI H9N2 by either HI or MN assays using ≥40 cut-off antibody titre. A total of 4.7% and 3.8% poultry workers were positive for antibodies against AI H9N2 by HI and MN assay respectively using 40 as cut-off antibody titre. This is the first report of seroprevalence of antibodies against AI H9N2 among poultry workers in India.


Shailesh D. Pawar, Babasaheb V. Tandale, Chandrashekhar G. Raut, Saurabh S. Parkhi, Tanaji D. Barde, Yogesh K. Gurav, Sadhana S. Kode, Akhilesh C. Mishra*

PLoS ONE 7(5): e36374. doi:10.1371/journal.pone.0036374

An engineered influenza virus based on a haemagglutinin protein from H5N1 avian influenza, with just four mutations, can be transmitted between ferrets, emphasizing the potential for a human pandemic to emerge from birds.

Hui-Ling Yen1 & Joseph Sriyal Malik Peiris1

Nature Year published: (2012)
doi:10.1038/nature11192

We previously described how retail meat, particularly chicken, might be a reservoir for extraintestinal pathogenic Escherichia coli (ExPEC) causing urinary tract infections (UTIs) in humans. To rule out retail beef and pork as potential reservoirs, we tested 320 additional E. coli isolates from these meats. Isolates from beef and pork were significantly less likely than those from chicken to be genetically related to isolates from humans with UTIs. We then tested whether the reservoir for ExPEC in humans could be food animals themselves by comparing geographically and temporally matched E. coli isolates from 475 humans with UTIs and from cecal contents of 349 slaughtered animals. We found genetic similarities between E. coli from animals in abattoirs, principally chickens, and ExPEC causing UTIs in humans. ExPEC transmission from food animals could be responsible for human infections, and chickens are the most probable reservoir.

Catherine Racicot Bergeron1, Catharine Prussing1, Patrick Boerlin, Danielle Daignault, Lucie Dutil2, Richard J. Reid-Smith, George G. Zhanel, and Amee R. Manges

Emerg Infect Dis [serial on the Internet] 2012 Mar [date cited]. Volume 18, Number 3—March 2012

According to researchers in Belgium, the number of human campylobacteriosis cases associated with chickens remains high because, although it is known that chickens are the number one risk factor for disease in humans, there are no effective strategies to reduce Campylobacter prevalence in flocks.

Hermans D., F. Pasmans, W. Messens, A Martel, F. Van Immerseel, G. Rasschaert, M. Heyndrickx, K. Van Deun and F. Haesebrouck. 2012.

Vector-Borne and Zoonotic Diseases. 12(2): 89-98. doi:10.1089/vbz.2011.0676

A quantitative understanding of the spread of contaminated farm dust between locations is a prerequisite for obtaining much-needed insight into one of the possible mechanisms of disease spread between farms. Here, we develop a model to calculate the quantity of contaminated farm-dust particles deposited at various locations downwind of a source farm and apply the model to assess the possible contribution of the wind-borne route to the transmission of Highly Pathogenic Avian Influenza virus (HPAI) during the 2003 epidemic in the Netherlands. The model is obtained from a Gaussian Plume Model by incorporating the dust deposition process, pathogen decay, and a model for the infection process on exposed farms. Using poultry- and avian influenza-specific parameter values we calculate the distance-dependent probability of between-farm transmission by this route. A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 epidemic reveals that the wind-borne route alone is insufficient to explain the observations although it could contribute substantially to the spread over short distance ranges, for example, explaining 24% of the transmission over distances up to 25 km.

Ssematimba A, Hagenaars TJ, de Jong MCM

(2012) PLoS ONE 7(2): e31114. doi:10.1371/journal.pone.0031114

Cambodia; environment;H5N1 virus; influenza; outbreaks; transmission risk

Background:  Very little is known regarding the persistence of highly pathogenic avian influenza H5N1 viruses in natural settings during outbreaks in tropical countries, although environmental factors may well play a role in the persistence and in the transmission of H5N1 virus.
Objective:  To investigate various environmental compartments surrounding outbreak areas as potential sources for H5N1 virus transmission.
Methods:  Environmental specimens were collected following outbreaks of avian influenza in Cambodia between April 2007 and February 2010. The methods used to concentrate H5N1 virus from water samples were based either on agglutination of the virus with chicken red blood cells or on adsorption on glass wool, followed by an elution-concentration step. An elution-concentration method was used for mud specimens. All samples that tested positive by real-time RT-PCRs (qRT-PCRs) targeting the HA5, M and NA1 genes were inoculated into embryonated hen eggs for virus isolation.
Results:  Of a total of 246 samples, 46 (19%) tested positive for H5N1 by qRT-PCRs. Viral RNA was frequently detected in dust, mud and soil samples from the farms’ environment (respectively, 46%, 31% and 15%). Samples collected from ponds gave a lower proportion of positive samples (6%) as compared to those collected from the farms (24%). In only one sample, infectious virus particles were successfully isolated.
Conclusion:  During H5N1 virus outbreaks, numerous environmental samples surrounding outbreak areas are contaminated by the virus and may act as potential sources for human and/or animal contamination.

Srey V. Horm, Ramona A. Gutiérrez, San Sorn, Philippe Buchy

In: Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750-2659.2012.00338.x.(2012)

North Carolina State University chemists have created a compound that makes existing antibiotics 16 times more effective against recently discovered antibiotic-resistant "superbugs."

Roberta J. Worthington, Cynthia A. Bunders, Catherine S. Reed, Christian Melander

ACS Medicinal Chemistry Letters, 2012; : 120209131248001 DOI: 10.1021/ml200290p

On March 15, 2010, a highly pathogenic avian influenza virus was isolated from the carcass of a common buzzard (Buteo buteo) in Bulgaria. Phylogenetic analyses of the virus showed a close genetic relationship with influenza virus A (H5N1) clade 2.3.2.1 viruses isolated from wild birds in the Tyva Republic and Mongolia during 2009–2010. Designated A/common buzzard/Bulgaria/38WB/2010, this strain was highly pathogenic in chickens but had low pathogenicity in mice and ferrets and no molecular markers of increased pathogenicity in mammals. The establishment of clade 2.3.2.1 highly pathogenic avian influenza viruses of the H5N1 subtype in wild birds in Europe would increase the likelihood of health threats to humans and poultry in the region.

Atanaska Marinova-Petkova, Georgi Georgiev, Patrick Seiler, Daniel Darnell, John Franks, Scott Krauss, Richard J. Webby, and Robert G. Webster

Emerg Infect Dis [Internet]. 2012 Oct [date cited].

Plans for restricted access to bird flu papers expected "within the next few weeks"

Heidi Ledford

Nature DOI: doi:10.1038/nature.2012.9784

Reservoirs for the continuing influenza (H5N1) outbreaks in Egypt are ill-defined. Through active surveillance, we detected highly pathogenic influenza subtype H5 viruses in all poultry sectors; incidence was 5%. No other subtypes were found. Continued circulation of influenza (H5N1) viruses in various regions and poultry sectors perpetuates human exposure in Egypt.

Ghazi Kayali, Rabeh El-Shesheny, Mohamed A. Kutkat, Ahmed M. Kandeil, Ahmed Mostafa, Mariette F. Ducatez, Pamela P. McKenzie, Elena A. Govorkova, Mohamed H. Nasraa, Robert G. Webster, Richard J. Webby, and Mohamed A. Ali

Emerg Infect Dis [serial on the Internet]. Volume 17, Number 12—December 2011 http://dx.doi.org/10.3201/eid1712.110683
DOI: 10.3201/eid1712.110683

Pheasant, partridge, flavivirus, Spain

In September 2010, an unusually high number of wild birds (partridges and pheasants) died in Cádiz in southwestern Spain. Reverse transcription PCR and virus isolation detected flavivirus infections. Complete nucleotide sequence analysis identified Bagaza virus, a flavivirus with a known distribution that includes sub-Saharan Africa and India, as the causative agent.

Montserrat Agüero, Jovita Fernández-Pinero, Dolores Buitrago, Azucena Sánchez, Maia Elizalde, Elena San Miguel, Ruben Villalba, Francisco Llorente, and Miguel Ángel Jiménez-Clavero

Emerg Infect Dis [serial on the Internet]. 2011 Aug [date cited]. Volume 17, Number 8—August 2011

Campylobacter; Slaughter; Carcass; Contamination; Broiler

A study was conducted in 2009 to identify risk factors of Campylobacter spp. transmission from the digestive tract to the carcasses of standard broilers (slaughter age: 37 day, carcass weight: 1.3 kg on average). Counts of Campylobacter were performed on pools of 10 ceca and 10 neck-skins from 108 Campylobacter ceca-positive batches in three slaughterhouses. Technical and health data also was collected on the broilers: age, size, carcass weight (mean and standard deviation), condemnation rate, mortality rate and nature of treatment during the rearing period.

Xavier Malhera,Matthieu Simona, Valérie Charnay, Rosine Danguy des Déserts, Anne Lehébela, Catherine Belloca

International Journal of Food Microbiology
Volume 150, Issue 1, 17 October 2011, Pages 8-13

Bronchite infettiva, variante, Italia

Identificazione della nuova variante Q1 di IBV in Italia

A. Toffan, C. Terregino, E. Mazzacan,I. Castaldello, I. Capua, M. Bonci

Veterinary Record | August 2011, Volume 169, Issue 8

The extensive circulation of the H5N1 highly pathogenic avian influenza (HPAI)virus in animals and the human health implications which it poses have led to extensive research in unexplored fields and thus a re-assessment of our understanding of this infection. Moreover, widespread infection of poultry has raised concerns about the food safety and trade implications of this infection,necessitating revised international trade regulations.

M.S. Beato & I. Capua

Rev. sci. tech. Off. int. Epiz., 2011, 30 (1), 51-61

Increasing international trade in poultry meat presents an opportunity for the global dissemination of poultry disease. However, it would be very unfortunate if expanding world trade resulted in animal diseases being used as unjustified nontariff trade barriers.
For those avian diseases currently listed by the World Organisation for Animal Health, the current evidence suggests that only highly pathogenic avian influenza, Newcastle disease, and (for chicken meat) infectious bursal disease should be considered likely to be spread though trade in this commodity.

S.P. Cobb

Rev. sci. tech. Off. int. Epiz., 2011, 30 (1), 149-164

Drug-resistant strains of Staphylococcus aureus, a bacterium linked to a wide range of human diseases are present in meat and poultry from U.S. grocery stores at unexpectedly high rates, according to a nationwide study by the Translational Genomics Research Institute

A. E. Waters, T. Contente-Cuomo, J. Buchhagen, C. M. Liu, L. Watson, K. Pearce, J. T. Foster, J. Bowers, E. M. Driebe, D. M. Engelthaler, P. S. Keim, L. B. Price.

Clinical Infectious Diseases, 2011; DOI: 10.1093/cid/cir181

Researchers in Bavaria suggest that the presence of thermo-tolerant Campylobacter on four per cent of the eggshells they tested may be a missing link for foodborne infections

U. Messelhusser*, D. Thrigen, D. Elmer-Englhard, H. Bauer, H. Schreiner, and C. Hòller

Appl. Environ. Microbiol. doi:10.1128/AEM.00145-11

This study was conducted to examine the in vitro activity of antimicrobials against Campylobacter spp. isolates from chicken and human sources and the genetic interrelation among them. The results suggest that MDR Campylobacter spp. are widespread and that Campylobacter with similar genotypes are circulating both in humans and in chicken meat in Korea.

Bok Kyung Ku, Hae Ji Kim, Young Ju Lee, Young Ihl Kim, Jung Su Choi, Mi Young Park, Jin Wook Kwon, Hyang-Mi Nam, Yong Hwan Kim, Suk-Chan Jung, Sun Jin Lee, Sang Hyun Kim, Jong Hyun Kim.

Foodborne Pathogens and Disease. March 2011, 8(3): 381-386. doi:10.1089/fpd.2010.0680.

tacchino, epatite, picornavirus

Viene riportata l'identificazione e caratterizzazione molecolare dell'agente della Epatite del tacchino. Si tratta di un nuovo PIcornavirus, diverso da quelli conosciuti e con caratteristiche peculiari. La realtime PCR sviluppata a fini diagnostici ha rivelato la presenza dell'agente oltreche a livello apatico anche nella bile, intestino, siero e tamponi cloacali. La presenz adi questo agente è stata riilevata in 8 gruppi campionati tra il 2008 e il 2010

Kirsi S. Honkavuori, H. L. Shivaprasad, Thomas Briese, Craig Street, David L. Hirschberg,Stephen, K. Hutchison, and W. Ian Lipkin

Emerging Infectious Diseases è www.cdc.gov/eid  Vol. 17, No. 3, March 2011

duck, egg-drop, flavivirus, BYD

Isolato un nuovo virus nelle anatre responsabile di una sindrome di calo di deposizione. Si tartta di un flavivirus chiamtao BYD
Il testo completo del lavoro è accessibile (free) al sito seguente:
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0018106

Su J, Li S, Hu X, Yu X,, Wang Y, et al.

PLoS ONE 6(3): e18106.
doi:10.1371/journal.pone.0018106.

"Highly Pathogenic Avian Influenza (H5N1): Pathways of Exposure at the Animal‐Human Interface, a Systematic Review"
The threat posed by highly pathogenic avian influenza A H5N1 viruses to humans remains significant, given the continued occurrence of sporadic human cases (499 human cases in 15 countries) with a high case fatality rate (approximately 60%), the endemicity in poultry populations in several countries, and the potential for reassortment with the newly emerging 2009 H1N1 pandemic strain. Therefore, we review risk factors for H5N1 infection in humans.

Maria D. Van Kerkhove, Elizabeth Mumford, Anthony W. Mounts, Joseph Bresee3, Sowath Ly4, Carolyn B. Bridges, Joachim Otte

PLoS ONE 6(1): e14582. doi:10.1371/journal.pone.0014582

"Antimicrobial Resistance of Major Foodborne Pathogens from Major Meat Products"
Il lavoro pubblicato è scaricabile dal seguente link: http://www.liebertonline.com/doi/abs/10.1089/fpd.2010.0577

Panagiota Gousia, Vagelis Economou, Hercules Sakkas, Stamatina Leveidiotou, Chrissanthy Papadopoulou.

Foodborne Pathogens and Disease. January 2011, 8(1): 27-38. doi:10.1089/fpd.2010.0577.

Prevalence of Antimicrobial Resistance Among Salmonella Isolates from Chicken in China"
Il lavoro pubblicato è scaricabile dal seguente link: http://www.liebertonline.com/doi/abs/10.1089/fpd.2010.0605

Yan Lu, Cong-Ming Wu, Guo-Juan Wu, Hong-Yu Zhao, Tao He, Xing-Yuan Cao, Lei Dai, Li-Ning Xia, Shang-Shang Qin, Jian-Zhong Shen.

Foodborne Pathogens and Disease. January 2011, 8(1): 45-53. doi:10.1089/fpd.2010.0605.

"Single-Dose Mucosal Immunization with a Candidate Universal Influenza Vaccine Provides Rapid Protection from Virulent H5N1, H3N2 and H1N1 Viruses"
Il lavoro pubblicato su un open source journal è scaricabile dal seguente link http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0013162


Price GE, Soboleski MR, Lo C-Y, Misplon JA, Quirion MR, et al. (2010)

PLoS ONE 5(10): e13162. doi:10.1371/journal.pone.0013162

Avian influenza. waterfowl, transmission

"Can Preening Contribute to Influenza A Virus Infection in Wild Waterbirds?"
Il lavoro pubblicato su un open source journal è scaricabile dal seguente link http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0011315

Mauro Delogu, Maria A. De Marco, Livia Di Trani, Elisabetta Raffini, Claudia Cotti, Simona Puzelli, Fabio Ostanello, Robert G. Webster, Antonio Cassone, Isabella Donatelli

PLoS ONE 5(6): e11315. doi:10.1371/journal.pone.0011315

Listeria monocytogenes, chicken, processing plant

"Colonization of a Newly Constructed Commercial Chicken Further Processing Plant with Listeria monocytogenes"
This study was undertaken to determine potential sources of Listeria monocytogenes in a newly constructed chicken further processing plant and document the eventual colonization of the facility by this pathogen.

prova

Journal of Food Protection, Volume 73, Number 2, February 2010 , pp. 286-291(6)

"The change in prevalence of Campylobacter on chicken carcasses during processing: A systematic review"
A systematic review was conducted to evaluate the change in prevalence of Campylobacter on chicken carcasses during processing.



Poult Sci 2010. 89:1070-1084.

Avian Influenza, migratory birds

"Outbreak Study: Satellite Tracking Reveals How Wild Birds May Spread Avian Flu"
For the first time, migratory birds marked with satellite transmitters were tracked during an outbreak of highly pathogenic H5N1 avian influenza virus (H5N1) in Asia, providing evidence that wild birds may be partly responsible for the spread of the virus to new areas.

The human respiratory tract is a major site of avian influenza A(H5N1) infection. However, many humans infected with H5N1 present with gastrointestinal tract symptoms, suggesting that this may also be a target for the virus. In this study, we demonstrated that the human gut expresses abundant avian H5N1 receptors, is readily infected ex vivo by the H5N1 virus, and produces infectious viral particles in organ culture. An autopsy colonic sample from an H5N1-infected patient showed evidence of viral antigen expression in the gut epithelium. Our results provide the first evidence, to our knowledge, that H5N1 can directly target human gut tissues.

Yuelong Shu, Chris Ka-fai Li, Zi Li et al.

The Journal of Infectious Diseases 2010;201:11731177

An intensive study of 443 isolates of Campylobacter jejuni and Campylobacter coli from 2031 fecal samples excreted by animal sources including cattle, sheep, and pigs, a range of wild and domesticated avian species and pets is described. The prevalence found in the majority of animal sources ranged from 22% to 28% with poultry being highest at 41% and cats and dogs lowest (<5%). The average count excreted for each animal source was found not to be significantly different ranging from approximately 102 to 105 cfu=g. Multilocus sequence typing (MLST)identified phylogenies that exhibited host specificity. A number of clonal complexes (CCs) and sequence types (STs) were characteristic of particular hosts (e.g., CC-179, ST-637, and ST-1341 found only in pigeons and gulls). Analysis of genetic distance demonstrated numerous significant differences in the distribution of MLST types (CC, ST, and allele) between animal sources. Host association was quantified using structure that correctly assigned the nine animal sources with accuracies of 28%, 24%, and 55% at the CC, ST, and allele levels, respectively. This is substantially higher than would be expected by random allocation (11%) but farmyard poultry had the lowest assignment accuracy (13%, 13%, and 21%) suggesting that isolates were shared with a wide range of other animals. This study demonstrates the link between MLST type and host and provides data that can be used in risk assessment and food attribution models. Further, it demonstrates the applicability of MLST to characterize Campylobacter strains from a broad range of environmental sources.

Iain D. Ogden, John F. Dallas, Marion MacRae, et al.

FOODBORNE PATHOGENS AND DISEASE
Volume 6, Number 10, 2009

Inmfluenza, genetica, uccelli migratori, trasmissione
Il ruolo che gli uccelli migratori rivestono nel movimento del virus influenzale H5N1 è oggetto di frequente dibattito. Allo scopo di approfondire l'argomento e di valutare il rischio reale che dall'Asia possano giungere in Nord America virus influenzali ad alta patogenicità (HPAI) tramite uccelli migratori, sono state condotte ricerche genetiche su virus influenzali a bassa patogenicità (LPAI), isolati in Alaska da una specie di anatre migranti (Anas acuta). Un'analisi completa del genoma dei ceppi virali isolati ha messo in evidenza una divergenza genetica di base tra i ceppi asiatici e quelli nord americani, ma ha anche permesso di rilevare, con elevata frequenza, uno scambio genetico di livello intercontinentale. In quasi la metà di 38 ceppi isolati in Alaska era presente almeno un segmento genetico più affine ai ceppi LPAI asiatici che non a quelli nord americani. Inoltre, le sequenze genetiche di alcuni ceppi LPAI asiatici presenti in una banca di geni apparivano più vicine a quelle dei ceppi isolati in Nord America che non a quelli isolati in Asia. Le ricerche esposte supportano ulteriormente il ruolo degli uccelli selvatici migratori nel trasferimento intercontinentale dei virus influenzali.



Genetic evidence of intercontinental movement of avian influenza in a migratory bird: the northern pintail (Anas acuta). Molecular Ecology, 17 (21), 4754-4762 (2008)

Influenza aviare, trasmissione, ambiente, epidemie, uccelli acquatici

Il virus dell'influenza Aviare (AIV) permane nelle popolazioni di uccelli acquatici in Nord America causando focolai rilevanti con una cadenza di 3-4 anni. I tentativi per spiegare tale periodicità e persistenza usando semplici modelli di trasmissione diretta non hanno dato risultati concreti. Spinti da un'evidenza empirica abbiamo valutato le possibilità di un modo di trasmissione ignorato fino ad oggi ovvero la trasmissione ambientale. E noto che gli uccelli infetti eliminano grandi quantità di virioni nell' ambiente, dove questi possono persistere per un tempo molto lungo. Abbiamo di conseguenza ipotizzato che, in aggiunta alla tradizionale trasmissione oro-fecale, gli uccelli potessero infestarsi per ingestione di particelle virali presenti da tempo nell'ambiente. Abbiamo quindi disegnato un nuovo modello ospite-patogeno che combina le modalità di trasmissione intra-stagionali, la migrazione e riproduzione inter-stagionale e le variazioni ambientali. L'analisi del modello ha generato 3 risultati principali: 1) la trasmissione ambientale crea un meccanismo di persistenza all'interno di piccole comunità dove le epidemie non possono essere perpetuate dalla sola trasmissione diretta. 2) la trasmissione ambientale fornisce una cauta spiegazione della periodicità (2-4 anni) dei focolai. 3) livelli molto bassi di trasmissione ambientale (es. pochi casi all'anno) sono sufficienti a consentire la persistenza dell'influenza aviare in popolazioni nelle quali altrimenti scomparirebbe.



The Role of Environmental Transmission in Recurrent Avian Influenza Epidemics. PLoS Comput Biol 5(4)2009.

Influenza aviare; Grippe; Vaccinazione; Vettori; Subunità

Sebbene sia stato stabilito come la panzoozia Asiatica da virus H5N1 sia soprattutto un problema di sanità animale, l'implicazione della salute umana ed il rischio di una pandemia hanno evidenziato la necessità di maggiori informazioni e di coordinazione per entrambe le medicine.
I virus H5 e H7 dell'influenza aviare (AI) hanno la proprietà di poter essere, quando presenti, molto patogeni e di diffondersi rapidamente tra i volatili degli allevamenti.
L'obiettivo finale della vaccinazione dei volatili è di poter ottenere la eradicazione della malattia.
Attualmente esistono infatti importanti differenze per il controllo della influenza aviare e per la grippe dell'uomo. Per prima cosa, contrariamente ai vaccini umani che debbono avere come antigeni al fine di una buona protezione, i virus presenti sul campo in pratica, i vaccini aviari debbono conferire una buona protezione nei riguardi del ceppo IAHP. Inoltre, mentre principalmente i vaccini umani debbono proteggere dalla sintomatologia clinica, i vaccini aviari debbono essere in grado di evitare la replicazione degli stessi virus in modo da permetterne il controllo della diffusione.
La presente ricerca ha avuto lo scopo di considerare queste differenze passando in rassegna gli attuali vaccini e quelli futuri nonchè le diversità nelle strategie vaccinali per i volatili.

Thierry van den Berg, Bàndicte Lambrecht, Sylvie Marchè, Mieke Steensels, Steven Van Borm, Michel Bublot

Microbiology and Infectious Disease 31(2008)121-65

Influenza aviare - H5N1 virus altamente patogeno influenza aviare - Malattia - Lesioni - Volatili - Mammiferi

Le manifestazioni cliniche delle infezioni da virus influenzali sono molto variabili dipendendo le stesse dalle specie animale, dalla loro sensibilità e dalla reazione all'infezione, come anche dal potere patogeno del virus responsabile della infezione. La variante H5N1, di cui ben nota ne è la patogeneticità, èresponsabile della influenza aviaria (HPAIV) derivante dal virus A/Goose/Guandong/96 (H5N1 HPAI) ed è responsabile, nel mondo, della infezione di diverse specie animali.
Comunque, nonostante le specie di animali ammalati sul campo con il virus H5N1 HPAI siano diverse da quelle infettate sperimentalmente al fine della ricerca, le manifestazioni cliniche sono simili. In alcune specie le lesioni anatomo patologiche agli organi interni sono notevoli e la morte avviene improvvisamente senza presenza di una sintomatologia clinica. Ciò particolarmente si verifica nella categoria dei pulcini e delle altre specie aviarie dell'ordine dei Galliformi. In altre specie predominano le manifestazioni nervose seguite rapidamente dalla morte. Ciò è stato particolarmente evidenziato nel gatto (Carnivora), nelle oche (Anseriformes), nei ratti (Struthioniformes), nei piccioni inoculati con alte dosi di virus (Columbifornes) e nelle oche infettate con H5N1 HPAIV isolato ancora nel 2002 (Anseriformes). In alcune altre specie l'infezione perdura a lungo con una sintomatologia che, comunque, può causare anche la morte come esito finale. Principalmente queste specie comprendono l'umana (Primates), furetto (Carnivora), topo (Rodentia), Cynamologous macaques (Primates). In fine alcune specie sono molto resistenti alla infezione con il virus H5N1 HPAIV non dimostrando nessuna manifestazione clinica della malattia. Queste specie comprendono il piccione (Columbiformes), le anatre (Anseriformes) infettate con il virus pre-2002 e i suini (Artiodactyla).
Si tratta di una pubblicazione in cui si considera, oltre alla classificazione delle specie di animali che si infettano, anche le singole manifestazioni cliniche e le lesioni anatomopatologiche; si prendono in esame la diagnostica della malattia e le ripercussioni che la stessa può causare nelle produzioni zootecniche comprendendovi anche i danni economici da essa derivati.

Carol J. Cardona, Zheng Xing, Christian E. Sandrock, Cristina E. Davis

Comparative immunology, Microbiology and Infectious Diseases (2008) pubblicazione in stampa

tossina, enterite necrotica

Un gruppo di ricercatori australiani ha individuato una tossina, denominata NetB, che pare svolga un ruolo chiave (a differenza della tossina alfa) nella patogenesi dell'enterite necrotica. L'articolo è scaricabile gratuitamente dal sito www.plospathogens.org.La scoperta apre nuove opportunità nello studio di questa patologia e nello sviluppo di presidi immunizzanti.

A.L.Keyburn e coll

PloS Pathogens 2008, vol.4 n.2 pag.26

bronchite infettiva, coronavirus, immunità

Lo studio della risposta immunitaria nei confronti del virus della bronchite infettiva è indispensabile dal punto di vista pratico per rispondere agli interrogativi relativi alla profilassi vaccinale: quali sierotipi impiegare, a che età vaccinare, quale immunità stimolare, quale organo proteggere e per quanto tempo.

Pascucci S.

gallina ovaiola, qualità del guscio, alimentazione

World Poultry pubblica una review di facile consultazione sulle principali cause di alterazione della qualità del guscio nella gallina ovaiola con particolare enfasi sulle problematiche di natura alimentare.

A.Dhawale

World Poultry 2008, vol.24 n.6 pag.20

fertilità, uova, temperatura

Poultry International pubblica i risultati di una prova in cui sono state valutate le conseguenze delle variazioni di temperatura in fase di pre-incubazione sulla fertilità delle uova.

K.Bramwell

Poultry International 2008, vol.47 n.8 pag.10

salmonella, infezione verticale, uovo

In questa ricerca viene studiata la capacità e l'efficienza con la quale alcuni sierotipi di Salmonella (tra cui S.enteritidis, S.thyphimurium, S.hadar e S.virchow) infettano l'uovo per via verticale.

I.Gantois e coll

Avian Pathology 2008, vol.37 n.4 pag.399

Dermanyssus gallinae, S.enteritidis, trasmissione, feci

L'abilità di Dermanyssus gallinae come vettore di microrganismi patogeni è nota da tempo. Questo lavoro prende in considerazione la trasmissione di S.enteritidis. i risultati sono interessanti. L'acaro sembra infatti in grado di infettarsi (e di trasmettere S.enteritidis) sia da animali con forma setticemica in atto sia per contatto da matrici contaminate come ad esempio le feci.

C.Valiente Moro e coll

Veterinary Microbiology 2007, vol.146 pag.329

avvelenamento, sodio, tacchino, acqua di bevanda

Viene descritto un caso clinico di avvelenamento da sodio in un gruppo di tacchini da carne. L'intossicazione è collegata alla presenza di residui di ipoclorito di sodio nelle cisterne dell'acqua di bevanda. Interessanti i dati analitici relativi alle concentrazioni di sodio rilevate negli organi degli animali colpiti.

R.Crespo e coll

Avian Diseases 2008, vol.52 pag.179

chicken; cost of immunity; ecological immunology; effect size; poultry; production trait; selection line; turkey

L'abstract è visualizzabile sul sito: http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2435.2010.01800.x/abstract

Peter J. Van Der Most1, Berber De Jong1, Henk K. Parmentier2, Simon Verhulst1,*

Functional Ecology Article first published online:
DOI: 10.1111/j.1365-2435.2010.01800.x

In September 2010, an unusually high number of wild birds (partridges and pheasants) died in Cádiz in southwestern Spain. Reverse transcription PCR and virus isolation detected flavivirus infections. Complete nucleotide sequence analysis identified Bagaza virus, a flavivirus with a known distribution that includes sub-Saharan Africa and India, as the causative agent.

Montserrat Agüero, Jovita Fernández-Pinero, Dolores Buitrago, Azucena Sánchez, Maia Elizalde, Elena San Miguel, Ruben Villalba, Francisco Llorente, and Miguel Ángel Jiménez-Clavero

Emerg Infect Dis [serial on the Internet]. 2011 Aug [date cited].

This study aimed to identify the sources and routes of transmission of Campylobacter in intensively reared poultry farms in the Republic of Ireland. Breeder flocks and their corresponding broilers housed in three growing facilities were screened for the presence of Campylobacter species from November 2006 through September 2007. All breeder flocks tested positive for Campylobacter species (with C. jejuni and C. coli being identified). Similarly, all broiler flocks also tested positive for Campylobacter by the end of the rearing period. Faecal and environmental samples were analyzed at regular intervals throughout the rearing period of each broiler flock. Campylobacter was not detected in the disinfected house, or in one-day old broiler chicks. Campylobacter jejuni was isolated from environmental samples including air, water puddles, adjacent broiler flocks and soil. A representative subset of isolates from each farm was selected for further characterization using flaA-SVR sub-typing and multi-locus sequence typing (MLST) to determine if same-species isolates from different sources were indistinguishable or not. Results obtained suggest that no evidence of vertical transmission existed and that adequate cleaning/disinfection of broiler houses contributed to the prevention of carryover and cross-contamination. Nonetheless, the environment appears to be a potential source of Campylobacter. The population structure of Campylobacter isolates from broiler farms in Southern Ireland was diverse and weakly clonal.

Emer O'Mahony, James F. Buckley, Declan Bolton, Paul Whyte, Séamus Fanning

PLoS ONE 6(12): e28490. doi:10.1371/journal.pone.0028490

In the Netherlands in 2003, an outbreak of avian influenza in poultry resulted in extensive culling, especially of layer hens. Concurrently, human campylobacteriosis cases decreased, particularly in the culling area. These observations raise the hypothesis that Campylobacter spp. dissemination from poultry farms or slaughterhouses might contribute to human campylobacteriosis.

Ingrid H.M. Friesema , Arie H. Havelaar, Paul P. Westra, Jaap A. Wagenaar, and Wilfrid van Pelt

Emerg Infect Dis [serial on the Internet]. 2012 Mar [date cited]. Volume 18, Number 3—March 2012

In March 2010, an outbreak of low pathogenicity avian influenza A (H10N7) occurred on a chicken farm in Australia. After processing clinically normal birds from the farm, 7 abattoir workers reported conjunctivitis and minor upper respiratory tract symptoms. Influenza virus A subtype H10 infection was detected in 2 workers.


George G. Arzey , Peter D. Kirkland, K. Edla Arzey, Melinda Frost, Patrick Maywood, Stephen Conaty, Aeron C. Hurt, Yi-Mo Deng, Pina Iannello, Ian Barr, Dominic E. Dwyer, Mala Ratnamohan, Kenneth McPhie, and Paul Selleck

Emerg. Infect. Dis. Volume 18, Number 5—May 2012 DOI: 10.3201/eid1805.111852

In order to investigate new hosts for Anaplasmataceae agents in Brazil, we collected blood samples from 21 wild birds. Using molecular techniques, we detected the presence of Anaplasma phagocytophilum, Ehrlichia chaffeensis, and an Ehrlichia species closely related to Ehrlichia canis in carnivorous avian blood samples. In addition, an Ehrlichia species closely related to an Ehrlichia species found in wild felines in Brazil was also detected in a goose blood sample. Wild birds may play a role as carriers of Anaplasmataceae agents in Brazil.

Rosangela Zacarias Machado, Marcos Rogério André, Karin Werther, Eliane de Sousa, Fernando Antônio Gavioli, and José Roberto Ferreira Alves Junior.

Vector-Borne and Zoonotic Diseases. August 2012, 12(8): 705-708. doi:10.1089/vbz.2011.0803.