Avian Influenza A(H5N1) Virus in Egypt

In Egypt, avian influenza A subtype H5N1 and H9N2 viruses are enzootic in poultry. The control plan devised by veterinary authorities in Egypt to prevent infections in poultry focused mainly on vaccination and ultimately failed. Recently, widespread H5N1 infections in poultry and a substantial increase in the number of human cases of H5N1 infection were observed. We summarize surveillance data from 2009 through 2014 and show that avian influenza viruses are established in poultry in Egypt and are continuously evolving genetically and antigenically. We also discuss the epidemiology of human infection with avian influenza in Egypt and describe how the true burden of disease is underestimated. We discuss the failures of relying on vaccinating poultry as the sole intervention tool. We conclude by highlighting the key components that need to be included in a new strategy to control avian influenza infections in poultry and humans in Egypt.     

宁乡县家禽养殖环境禽流感病毒监测分析

目的对宁乡县家禽养殖环境进行禽流感病毒(Avian influenza virus,AIV)监测,了解环境中AIV的分布状况。方法 2010年从3个禽类环境监测点(家禽散养户、规模化养殖交易场所和规模化养殖场)共采集环境标本80份,real-time PCR方法检测环境标本(污水、禽类粪便和禽类笼具表面涂抹标本)AIV核酸。结果监测数据显示,80份环境标本中检出20份AIV核酸阳性,阳性率为25%;17份H5亚型AIV阳性,阳性率21.25%。家禽散养户H5亚型AIV核酸阳性率最高,阳性率为30%,其次为规模化养殖交易场所和规模化养殖场,阳性率分别为23.33%和13.33%;不同环境标本H5亚型AIV标本检出率不同,其中污水标本阳性率最高,阳性率41.67%,显著高于粪便和笼具涂抹样的阳性率。结论宁乡县家禽养殖环境标本中H5亚型AIV核酸阳性率较高,各监测点需要及时对环境进行清扫和消毒,以减少H5亚型AIV传播至人的风险。     

No Evidence of Infection With Avian Influenza Viruses Among US Poultry Workers in the Delmarva Peninsula,Maryland and Virginia,USA

ABSTRACT

Industrial poultry workers may be at elevated risk of avian influenza infection due to intense occupational contact with live poultry. Serum samples from poultry workers and community members in the Delmarva Peninsula, one of the densest regions of poultry production in the United States, were analyzed for antibodies to strains of five avian influenza subtypes using microneutralization assays. No evidence of infection was found, suggesting inefficient transmission to humans or the absence of virus in these premises. Continued serological surveillance of workers in industrial food animal facilities is necessary to prevent the transmission of influenza A viruses.     

Novel Reassortant Avian Influenza A(H5N6) Virus,China, 2021

Although reports of human infection with influenza A(H5N6) increased in 2021, reports of similar H5N6 virus infection in poultry are few. We detected 10 avian influenza A(H5N6) clade 2.3.4.4b viruses in poultry from 4 provinces in China. The viruses showed strong immune-escape capacity and complex genetic reassortment, suggesting further transmission risk.     

Continuing threat of influenza (H5N1) virus circulation in Egypt

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.     

Equine-Like H3 Avian Influenza Viruses in Wild Birds,Chile

Since their discovery in the United States in 1963, outbreaks of infection with equine influenza virus (H3N8) have been associated with serious respiratory disease in horses worldwide. Genomic analysis suggests that equine H3 viruses are of an avian lineage, likely originating in wild birds. Equine-like internal genes have been identified in avian influenza viruses isolated from wild birds in the Southern Cone of South America. However, an equine-like H3 hemagglutinin has not been identified. We isolated 6 distinct H3 viruses from wild birds in Chile that have hemagglutinin, nucleoprotein, nonstructural protein 1, and polymerase acidic genes with high nucleotide homology to the 1963 H3N8 equine influenza virus lineage. Despite the nucleotide similarity, viruses from Chile were antigenically more closely related to avian viruses and transmitted effectively in chickens, suggesting adaptation to the avian host. These studies provide the initial demonstration that equine-like H3 hemagglutinin continues to circulate in a wild bird reservoir.     

Highly Pathogenic Avian Influenza A(H5N8) Clade 2.3.4.4b Virus in Dust Samples from Poultry Farms,France, 2021

Avian influenza A(H5N8) virus has caused major epizootics in Europe since 2016. We conducted virologic analysis of aerosol and dust collected on poultry farms in France during 2020–2021. Our results suggest dust contributes to viral dispersal, even early in an outbreak, and could be a valuable surveillance tool.     

Highly Pathogenic Avian Influenza A(H7N3) Virus in Poultry Workers,Mexico, 2012

We identified 2 poultry workers with conjunctivitis caused by highly pathogenic avian influenza A(H7N3) viruses in Jalisco, Mexico. Genomic and antigenic analyses of 1 isolate indicated relatedness to poultry and wild bird subtype H7N3 viruses from North America. This isolate had a multibasic cleavage site that might have been derived from recombination with host rRNA.     

Highly Pathogenic Avian Influenza A(H7N3) Virus in Poultry,United States, 2020

An outbreak of low-pathogenicity avian influenza A(H7N3) virus of North American wild bird lineage occurred on commercial turkey farms in North Carolina and South Carolina, USA, during March–April 2020. The virus mutated to the highly pathogenic form in 1 house on 1 farm via recombination with host 28S rRNA.     

Avian Influenza in Wild Birds, Central Coast of Peru

To determine genotypes of avian influenza virus circulating among wild birds in South America, we collected and tested environmental fecal samples from birds along the coast of Peru, June 2006–December 2007. The 9 isolates recovered represented 4 low-pathogenicity avian influenza strains: subtypes H3N8, H4N5, H10N9, and H13N2.     

Low Pathogenicity Avian Influenza (H5N2) Viruses,Dominican Republic

Low pathogenicity avian influenza (H5N2) virus was detected in poultry in the Dominican Republic in 2007 and re-emerged in 2017. Whole-genome sequencing and phylogenetic analysis show introduction of an H5N2 virus lineage from Mexico into poultry in the Dominican Republic, then divergence into 3 distinct genetic subgroups during 2007–2019.     

Effectiveness of Personal Protective Equipment and Oseltamivir Prophylaxis during Avian Influenza A (H7N7) Epidemic, the Netherlands, 2003

We analyzed the effectiveness of personal protective equipment and oseltamivir use during the 2003 avian influenza A (H7N7) epidemic in the Netherlands by linking databases containing information about farm visits, human infections, and use of oseltamivir and personal protective equipment. Using a stringent case definition, based on self-reported conjunctivitis combined with a positive hemagglutination-inhibition assay, we found that prophylactic treatment with oseltamivir significantly reduced the risk for infection per farm visit from 0.145 (95% confidence interval [CI] 0.078–0.233) to 0.031 (95% CI 0.008–0.073). The protective effect was ≈79% (95% CI 40%–97%). These results are comparable with the reported effect of prophylactic treatment with oseltamivir on human seasonal influenza. No significant protective effect was found for use of respirators or safety glasses, possibly because of limitations of the data.     

流行性感冒疫苗免疫现状与展望

流行性感冒(流感)是一种急性呼吸道传染病,在幼儿和老年人中常导致严重并发症。流感疫苗接种是目前预防流感最有效的措施。该文对现行流感灭活疫苗的免疫效果和免疫策略、其它类型流感疫苗和接种途径的研究状况、禽流感及其预防措施进行了综述。     

深圳市禽类销售人员预防人禽流感健康传播研究

目的通过对深圳市龙岗区禽类销售人员进行健康教育和危险因素的强化干预,评价预防人感染禽流感健康传播活动的效果。方法采用横断面调查方法,面对面询问调查对象,进行多种形式的健康传播活动1个月,干预前后数据的比较采用X^2检验．采取整群抽样方法,于2006年12月-2007年2月选取深圳市龙岗区28个大型农贸市场和三乌批发市场的禽类销售人员作为调查对象。结果人禽流感核心信息的知晓率干预后均有不同程度的上升。结论本次为期1个月的防治人禽流感健康传播活动取得了较好的效果,说明针对高危人群开展的防治人禽流感健康教育活动与突击性的宣传月活动相结合,在提高禽类销售人员自我防护能力、普及人禽流感防治知识等方面均有强化传播效果的作用。     

Human Case of Swine Influenza A (H1N1) Triple Reassortant Virus Infection, Wisconsin

Zoonotic infections with swine influenza A viruses are reported sporadically. Triple reassortant swine influenza viruses have been isolated from pigs in the United States since 1998. We report a human case of upper respiratory illness associated with swine influenza A (H1N1) triple reassortant virus infection that occurred during 2005 following exposure to freshly killed pigs.