Novel Clade 2.3.4.4b Highly Pathogenic Avian Influenza A H5N8 and H5N5 Viruses in Denmark, 2020

Since late 2020, outbreaks of H5 highly pathogenic avian influenza (HPAI) viruses belonging to clade 2.3.4.4b have emerged in Europe. To investigate the evolutionary history of these viruses, we performed genetic characterization on the first HPAI viruses found in Denmark during the autumn of 2020. H5N8 viruses from 14 wild birds and poultry, as well as one H5N5 virus from a wild bird, were characterized by whole genome sequencing and phylogenetic analysis. The Danish H5N8 viruses were found to be genetically similar to each other and to contemporary European clade 2.3.4.4b H5N8 viruses, while the Danish H5N5 virus was shown to be a unique genotype from the H5N5 viruses that circulated at the same time in Russia, Germany, and Belgium. Genetic analyses of one of the H5N8 viruses revealed the presence of a substitution (PB2-M64T) that is highly conserved in human seasonal influenza A viruses. Our analyses showed that the late 2020 clade 2.3.4.4b HPAI H5N8 viruses were most likely new incursions introduced by migrating birds to overwintering sites in Europe, rather than the result of continued circulation of H5N8 viruses from previous introductions to Europe in 2016/2017 and early 2020.     

Human Exposure to Live Poultry and Psychological and Behavioral Responses to Influenza A(H7N9), China

To investigate human exposure to live poultry and changes in risk perception and behavior after the April 2013 influenza A(H7N9) outbreak in China, we surveyed 2,504 urban residents in 5 cities and 1,227 rural residents in 4 provinces and found that perceived risk for influenza A(H7N9) was low. The highest rate of exposure to live poultry was reported in Guangzhou, where 47% of those surveyed reported visiting a live poultry market >1 times in the previous year. Most (77%) urban respondents reported that they visited live markets less often after influenza A(H7N9) cases were first identified in China in March 2013, but only 30% supported permanent closure of the markets to control the epidemic. In rural areas, 48% of respondents reported that they raised backyard poultry. Exposure to live commercial and private poultry is common in urban and rural China and remains a potential risk factor for human infection with novel influenza viruses.     

2016—2018年长沙市人群及活禽市场环境H5N6亚型禽流感病毒监测分析

目的:开展2016—2018年长沙市人群感染和活禽市场(live poultry markets, LPMs)环境污染H5N6亚型禽流感病毒(avian influenza virus, AIV)监测,为防控人感染H5N6亚型AIV提供实验室数据。方法:采集2016—2018年长沙市流感样病例和不明原因肺炎病例咽拭子6...     

On‐farm Study of Human Contact Networks to Document Potential Pathways for Avian Influenza Transmission between Commercial Poultry Farms in Ontario,Canada

Human movements associated with poultry farming create contact networks that might facilitate transmission of avian influenza (AI) between farms during outbreaks. In Canada, no information is available about how these networks connect poultry farms. The purpose of this study was to document human contacts between commercial poultry farms in Ontario, Canada, to learn how AI might be transmitted during outbreaks. We used face‐to‐face interviews with people entering the farm biosecurity perimeter on four layer, one turkey and three broiler breeder poultry farms in Ontario to collect information on between‐farm contacts and biosecurity practices. Over a four‐day study period on each farm, a median of 10.5 people entered the farm biosecurity perimeter (range 2–31). Ninety‐six per cent (111/118) of people consented to be interviewed. Of these, fifty‐three per cent (59/111) had contact with one or more (median 2, degree range 1–14) other poultry farms within 72 h. A median of 25 (range 7–65) human contacts linked study farms to other poultry farms. The mean distance of between‐farm contacts was 53 km. Eighty‐six per cent of people who answered the biosecurity questions (94/109) reported using one or more biosecurity practices. However, on 7/8 farms, at least one person reported that they did not use any biosecurity practices. Fifty per cent of social visitors used biosecurity, whereas 96% of all other people used biosecurity. Ninety‐two per cent of people that entered the poultry barns (46/50) used one or more biosecurity practices, whereas 81% of people (48/59) that did not enter the poultry barns used one or more biosecurity practices. Because our study documented farm visitors who did not use any biosecurity practices and moved between commercial poultry farms, we suggest that rapid trace‐out of human movements is as important as containment zoning to limiting disease spread during an outbreak of highly pathogenic AI in Ontario.     

石墨炉原子吸收光谱法测定禽、畜肝组织中镉

目的建立禽、畜肝组织中镉（cd）的石墨炉原子吸收光谱分析的方法。方法采用混合酸体系消解样品，以NHM2PO。＋Mg（N03）：作基体改进剂，石墨炉原子吸收光谱法定量。结果本方法在0-5.0μg/L浓度范围内，相关系数r=0．9994，方法的相对标准偏差（RSD％）为2．9—6．8，对国家标准物质：猪肝（GBW08551）、大米粉（GBW10010），杨树叶（GBW08513）中cd的测定值均在标准值范围。结论本方法具有方法简便、灵敏度高、稳定性好的特点，适用于禽、畜肝组织中Cd含量的测定。     

禽类及非禽类从业人员禽流感认知状况调查

目的 了解广东省东莞市禽类从业人员和非禽类从业人员人禽流感知识、态度和行为状况,为制定人禽流感防控措施提供依据.方法 对259名禽类和129名非禽类从业人员进行人禽流感知识、态度、行为调查.结果 禽类和非禽类从业人员人禽流感相关知识总知晓率分别为34.03%和29.75%.农贸市场及批发市场销售的家禽95.83%有检疫证明,但散养家禽禽流感疫苗接种率仅为62.69%.禽类从业人员每天穿工作服、戴手套、戴口罩人数所占比例分别为19.79%,32.81%和29.17%.禽类和非禽类从业人员对病死禽能采取正确处理措施的分别占25.87%和21.71%;接触病死禽后能每次洗手的分别占81.85%和92.25%;对"家禽实行定点屠宰,禁售活禽"的赞成率分别为20.08%和31.78%;对"定期对市场进行清洗消毒、宰杀当天所有活禽"的支持率分别为33.98%和54.26%.结论 东莞市禽类从业人员存在人禽流感防治知识缺乏、个人防护不足、对病死禽处理措施欠妥、散养家禽禽流感疫苗接种率偏低等现象.应加强宣传教育和管理措施.     

Residues of tetracycline compounds in poultry products in the eastern province of Saudi Arabia

Chicken muscle, liver and egg samples were collected from 33 broiler and 5 layer farms in the eastern province of Saudi Arabia over a period of two years starting from January 1996. Antibiotic-residue positive samples were identified in the products of 23 (69.7%) broiler and 3 (60%) layer poultry farms. 87% and 100.0% of the antibiotic-residue positive broiler farms were positive for at least one tetracycline compound in raw muscle and liver respectively, while 73.9% and 95.5% were positive for 2 or more tetracyclines in these two tissues, respectively. Furthermore, 82.6% and 95.5% of the antibiotic-residue-positive farms had mean concentrations of at least one tetracycline compound in excess of the permissible maximum residue limit (MRL) in raw muscle and liver, respectively. These compounds also remained chemically detectable after cooking. Tetracycline levels exceeded MRL in 14.4% of antibiotic-positive raw eggs but the overall mean tetracycline concentration in each farm was below MRL. This study confirmed widespread misuse of tetracycline agents including multiple use of drugs belonging to the same pharmacological group and lack of implementation of recommended withdrawal times. This may be contributing to the high resistance rates to tetracyclines in both chicken and human microbial isolates observed in the region. This study, therefore, stresses the need for stricter regulations for the use of antimicrobial drugs in the poultry industry as well as the inspection of chicken for drug residues prior to marketing.