Pet‐associated Campylobacteriosis: A persisting public health concern

Campylobacter is regarded as a leading cause of human bacterial gastroenteritis in the United States. We report on a case of laboratory‐confirmed Campylobacter jejuni infection in the Commonwealth of Pennsylvania among members of a household living with a laboratory‐confirmed but non‐speciated Campylobacter‐infected puppy. We describe an outbreak of likely dog‐associated campylobacteriosis, the risk factors, potential routes of exposure and the clinical features in the exposed family members, which began shortly after exposure to the recently purchased dog. We also provide public health recommendations to prevent Campylobacter infections in veterinary care providers, pet owners and those planning to adopt pets in the future. Finally, this report underscores the importance of the One Health approach when public health responders, human and animal healthcare providers and clinical diagnostic laboratories are tasked with developing effective strategies when investigating, detecting and responding to zoonoses (diseases shared between animals and humans).     

Concurrent 2009 Pandemic Influenza A (H1N1) Virus Infection in Ferrets and in a Community in Pennsylvania

We report a fall 2010 cluster of pandemic influenza A/H1N1 (pH1N1) infections in pet ferrets in Lehigh Valley region of Pennsylvania. The ferrets were associated with one pet shop. The influenza cluster occurred during a period when the existing human surveillance systems had identified little to no pH1N1 in humans in the Lehigh Valley, and there were no routine influenza surveillance systems for exotic pets. The index case was a 2.5‐month‐old neutered male ferret that was presented to a veterinary clinic with severe influenza‐like illness (ILI). In response to laboratory notification of a positive influenza test result, and upon request from the Pennsylvania Department of Health (PADOH), the Pennsylvania Department of Agriculture (PDA) conducted an investigation to identify other ill ferrets and to identify the source and extent of infection. PDA notified the PADOH of the pH1N1 infection in the ferrets, leading to enhanced human surveillance and the detection of pH1N1 human infections in the surrounding community. Five additional ferrets with ILI linked to the pet shop were identified. This simultaneous outbreak of ferret and human pH1N1 demonstrates the important link between animal health and public health and highlights the potential use of veterinary clinics for sentinel surveillance of diseases shared between animals and humans.     

Public Health and Vector‐Borne Diseases – A New Concept for Risk Governance

Public Health is defined as an interdisciplinary multilevel approach that deals with questions of preventing diseases at the population level. In this context, this paper focuses on vector‐borne diseases as an important threat with an increasing impact on human and animal health. Emphasis is laid on an integrated health approach (‘One‐Health’ initiative) as it recognizes the interrelated nature of both human and animal health. The importance of vector‐borne diseases to new and emerging diseases in Europe was demonstrated, for example, by the recent outbreak of West Nile virus infections in Greece, Northern Italy and Hungary; the spread of Crimean‐Congo haemorrhagic fever virus across Turkey, south‐western countries of the former USSR and the Balkans; the dramatic increase in hantavirus infections in Germany in 2012; and the dengue virus outbreak in Portugal in the same year. This paper provides a systematic approach for the analysis, assessment and governance of emerging health risks attributed to vector‐borne diseases by using a holistic approach developed by the International Risk Governance Council (IRGC), called the ‘IRGC Risk Governance Framework’. It can be used by decision‐makers and general Public Health authorities in order to evaluate the situation regarding any specific pathogen or Public Health risk and to decide if additional measures should be implemented.     

Swine Influenza in Sub‐Saharan Africa – Current Knowledge and Emerging Insights

Pigs have been associated with several episodes of influenza outbreaks in the past and are considered to play a significant role in the ecology of influenza virus. The recent 2009 pandemic influenza A/H1N1 virus originated from swine and not only did it cause widespread infection in humans, but was also transmitted back to swine in Asia, Europe and America. What may be the prevailing situation in Africa, particularly in sub‐Saharan Africa, with respect to the circulation of classical swine or pandemic influenza? The ecology of influenza viruses, as well as the epidemiology of human or animal influenza, is poorly understood in the region. In particular, little is known about swine influenza in Africa despite the relevance of this production in the continent and the widespread pig husbandry operations in urban and rural areas. In this review, the gap in the knowledge of classical and pandemic swine influenza is attributed to negligence of disease surveillance, as well as to the economic and public health impact that the disease may cause in sub‐Saharan Africa. However, emerging serological and virological evidence of swine influenza virus in some countries in the region underscores the importance of integrated surveillance to better understand the circulation and epidemiology of swine influenza, a disease of global economic and public health importance.     

Chinese poultry farmers' decision‐making for avian influenza prevention: a qualitative analysis

Poultry farmers faced dual risk when mutant avian influenza (AI) virus showed the zoonotic characteristics. A/H5N1 and A/H7N9 were two dominant AI virus strains that have captured the attention of the public over the years for they have been reported to bring about greater loss to poultry and human, respectively. Previous studies mainly used quantitative methods investigating either the means that poultry farmers adopted for protecting their poultry against A/H5N1 infection or the poultry farmers' self‐protective behaviours against A/H7N9 infection. We sought insights into the underlying factors influencing Chinese poultry farmers' protective behaviours in response to the dual risk of AI by a qualitative way. Semi‐structured in‐depth interviews were conducted with 25 Chinese chicken farmers recruited by purposive sampling between November 2016 and May 2017, the peak season of AI. All interviews were audio‐taped, transcribed and analysed using a grounded theory approach. From participants' experiences, we revealed five main themes: Measures adopted for protecting poultry and farmers, Emotional response to the AI epidemic, Perceived risk of AI, Perceived effectiveness of the preventive measures adopted and Perceived self‐efficacy to take preventive measures. The information of AI outbreak directly triggered Chinese chicken farmers' emotional response and thereafter preventive actions. Compared to the perceived risk of poultry infection with A/H5N1 which mainly connected to economic loss, participants perceived much lower risk of human infection with A/H7N9. AI epidemic information played a key role triggering poultry farmers' response behaviours. Chinese poultry farmers weighted more attention on the risk of poultry infection which was highly associated with economic losses. The government should build and improve an early AI warning and information transmission network to poultry farmers. Further reinforcement of related self‐protective and preventive knowledge training towards poultry farmers is necessary.     

Field Epidemiology and Laboratory Training Programs in West Africa as a model for sustainable partnerships in animal and human health

The concept of animal and human health experts working together toward a healthier world has been endorsed, but challenges remain in identifying concrete actions to move this one health concept from vision to action. In 2008, as a result of avian influenza outbreaks in West Africa, international donor support led to a unique opportunity to invest in Field Epidemiology and Laboratory Training Programs (FELTPs) in the region that engaged the animal and human health sectors to strengthen the capacity for prevention and control of zoonotic diseases. The FELTPs mixed 25% to 35% classroom and 65% to 75% field-based training and service for cohorts of physicians, veterinarians, and laboratory scientists. They typically consisted of a 2-year course leading to a master's degree in field epidemiology and public health laboratory management for midlevel public health leaders and competency-based short courses for frontline public health surveillance workers. Trainees and graduates work in multidisciplinary teams to conduct surveillance, outbreak investigations, and epidemiological studies for disease control locally and across borders. Critical outcomes of these programs include development of a cadre of public health leaders with core skills in integrated disease surveillance, outbreak investigation, vaccination campaigns, laboratory diagnostic testing, and epidemiological studies that address priority public health problems. A key challenge exists in identifying ways to successfully scale up and transform this innovative donor-driven program into a sustainable multisectoral one health workforce capacity development model.     

Do animal exhibitors support and follow recommendations to prevent transmission of variant influenza at agricultural fairs? A survey of animal exhibitor households after a variant influenza virus outbreak in Michigan

Influenza A viruses circulate in swine and can spread rapidly among swine when housed in close proximity, such as at agricultural fairs. Youth who have close and prolonged contact with influenza‐infected swine at agricultural fairs may be at increased risk of acquiring influenza virus infection from swine. Animal and human health officials have issued written measures to minimize influenza transmission at agricultural exhibitions; however, there is little information on the knowledge, attitudes, and practice (KAP) of these measures among animal exhibitors. After an August 2016 outbreak of influenza A(H3N2) variant (“H3N2v”) virus infections (i.e., humans infected with swine influenza viruses) in Michigan, we surveyed households of animal exhibitors at eight fairs (including one with known H3N2v infections) to assess their KAP related to variant virus infections and their support for prevention measures. Among 170 households interviewed, most (90%, 151/167) perceived their risk of acquiring influenza from swine to be low or very low. Animal exhibitor households reported high levels of behaviours that put them at increased risk of variant influenza virus infections, including eating or drinking in swine barns (43%, 66/154) and hugging, kissing or snuggling with swine at agricultural fairs (31%, 48/157). Among several recommendations, including limiting the duration of swine exhibits and restricting eating and drinking in the animal barns, the only recommendation supported by a majority of households was the presence of prominent hand‐washing stations with a person to monitor hand‐washing behaviour (76%, 129/170). This is a unique study of KAP among animal exhibitors and highlights that animal exhibitor households engage in behaviours that could increase their risk of variant virus infections and have low support for currently recommended measures to minimize infection transmission. Further efforts are needed to understand the lack of support for recommended measures and to encourage healthy behaviours at fairs.     

山东省首起野生天鹅H5N8高致病性禽流感疫情的紧急调查及处置

2021年1月12—19日,山东黄河三角洲国家级自然保护区大汶流管理站出现35只死亡的野生疣鼻天鹅。经现场调查,市级和省级实验室检测,诊断为疑似H5N8亚型高致病性禽流感,经国家禽流感参考实验室进行病毒分离鉴定,最终确定为H5N8亚型高致病性禽流感疫情。疫情发生后,通过现场调查、座谈及实验室检测等方式,对此次疫情开展了紧急流行病学调查,追溯疫情的可能来源,分析疫情的扩散风险,继而提出针对性的应急处置措施。调查发现,此次疫情由迁徙候鸟带毒引入引起的可能性较大;野生鸟类未及时开展免疫,导致体内抗体水平低下是疫情暴发的内源因素。由于迅速采取了合理的应急处理措施,此次疫情得到迅速控制,避免了疫情扩散。本次疫情警示,必须切实做好禽流感的强制免疫和监测工作,高度重视自然保护区及其附近场所珍稀禽类的免疫,以降低疫情发生风险。     

Contact Variables for Exposure to Avian Influenza H5N1 Virus at the Human–Animal Interface

Although the highly pathogenic avian influenza H5N1 virus continues to cause infections in both avian and human populations, the specific zoonotic risk factors remain poorly understood. This review summarizes available evidence regarding types of contact associated with transmission of H5N1 virus at the human–animal interface. A systematic search of the published literature revealed five analytical studies and 15 case reports describing avian influenza transmission from animals to humans for further review. Risk factors identified in analytical studies were compared, and World Health Organization‐confirmed cases, identified in case reports, were classified according to type of contact reported using a standardized algorithm. Although cases were primarily associated with direct contact with sick/unexpectedly dead birds, some cases reported only indirect contact with birds or contaminated environments or contact with apparently healthy birds. Specific types of contacts or activities leading to exposure could not be determined from data available in the publications reviewed. These results support previous reports that direct contact with sick birds is not the only means of human exposure to avian influenza H5N1 virus. To target public health measures and disease awareness messaging for reducing the risk of zoonotic infection with avian influenza H5N1 virus, the specific types of contacts and activities leading to transmission need to be further understood. The role of environmental virus persistence, shedding of virus by asymptomatic poultry and disease pathophysiology in different avian species relative to human zoonotic risk, as well as specific modes of zoonotic transmission, should be determined.     

A Multistate Investigation of Antibiotic‐Resistant Salmonella enterica Serotype I 4,[5],12:i:‐ Infections as Part of an International Outbreak Associated with Frozen Feeder Rodents

While most human Salmonella infections result from exposure to contaminated foods, an estimated 11% of all Salmonella infections are attributed to animal exposures, including both direct animal handling and indirect exposures such as cleaning cages and handling contaminated pet food. This report describes the epidemiologic, environmental and laboratory investigations conducted in the United States as part of the response to an international outbreak of tetracycline‐resistant Salmonella enterica serotype I 4,[5],12:i:‐ infections with over 500 illnesses occurring from 2008 to 2010. This investigation found that illness due to the outbreak strain was significantly associated with exposure to pet reptiles and frozen feeder rodents used as food for pet reptiles. Salmonella isolates indistinguishable from the outbreak strain were isolated from a frozen feeder mice‐fed reptile owned by a case patient, as well as from frozen feeder mice and environmental samples collected from a rodent producing facility (Company A). An international voluntary recall of all Company A produced frozen feeder animals sold between May 2009 and July 2010 occurred. Only 13% of cases in our investigation were aware of the association between Salmonella infection and mice or rats. Consumers, the pet industry, healthcare providers and veterinarians need to be aware of the potential health risk posed by feeder rodents, whether live or frozen. Frozen feeder rodent producers, suppliers and distributors should follow the animal food labelling requirements as described in 21 CFR §501.5, and all packages of frozen feeder rodents should include safe handling instructions. Persons should wash their hands thoroughly with soap and water after handling live or frozen feeder rodents, as well as reptiles or anything in the area where the animals live. Continued opportunities exist for public health officials, the pet industry, veterinarians and consumers to work together to prevent salmonellosis associated with pet food, pets and other animals.     

Multistate Outbreak of Human Salmonella Typhimurium Infections Linked to Pet Hedgehogs – United States, 2011–2013

Zoonotic Salmonella infections cause approximately 130 000 illnesses annually in the United States. Of 72.9 million US households owning at least one pet, five million own small mammals; 3000 hedgehogs were documented by USDA in USDA‐licensed breeding facilities and pet stores in 2012. State health department collaborators and PulseNet, the national bacterial subtyping network, identified human infections of a Salmonella Typhimurium outbreak strain, which were investigated by CDC, USDA‐APHIS and state public and animal health officials. A case was defined as an illness in a person infected with the outbreak strain identified between 1 December 2011 and 3 June 2013. Investigators collected information on patient exposures, cultured animal and environmental specimens for Salmonella, and conducted traceback investigations of USDA‐licensed hedgehog facilities. There were 26 cases in 12 states. Illness onset dates ranged from 26 December 2011 to 8 April 2013. The median patient age was 15 years (range = <1–91 years); 58% were female. Among 23 persons with available information, 8 (35%) were hospitalized and one outbreak strain‐associated death was reported. Of 25 patients with available information, 20 (80%) reported pet hedgehog contact in the week before illness onset. The outbreak strain was isolated from animal and environmental samples collected from three ill persons’ homes in three states. Hedgehogs were purchased in geographically distant states from USDA‐licensed breeders (10/17, 59%); a USDA‐licensed pet store (1/17, 6%); unlicensed or unknown status breeders (3/17, 18%); and private individuals (3/17, 18%). Traceback investigations of USDA‐licensed facilities did not reveal a single source of infection. Public and animal health collaboration linked pet hedgehog contact to human infections of Salmonella Typhimurium, highlighting the importance of a One Health investigative approach to zoonotic salmonellosis outbreaks. More efforts are needed to increase awareness among multiple stakeholders on the risk of illness associated with pet hedgehogs.     

Development of Disease‐specific,Context‐specific Surveillance Models: Avian Influenza (H5N1)‐Related Risks and Behaviours in African Countries

Avian influenza virus (H5N1) is a rapidly disseminating infection that affects poultry and, potentially, humans. Because the avian virus has already adapted to several mammalian species, decreasing the rate of avian–mammalian contacts is critical to diminish the chances of a total adaptation of H5N1 to humans. To prevent the pandemic such adaptation could facilitate, a biology‐specific disease surveillance model is needed, which should also consider geographical and socio‐cultural factors. Here, we conceptualized a surveillance model meant to capture H5N1‐related biological and cultural aspects, which included food processing, trade and cooking‐related practices, as well as incentives (or disincentives) for desirable behaviours. This proof of concept was tested with data collected from 378 Egyptian and Nigerian sites (local [backyard] producers/live bird markets/village abattoirs/commercial abattoirs and veterinary agencies). Findings revealed numerous opportunities for pathogens to disseminate, as well as lack of incentives to adopt preventive measures, and factors that promoted epidemic dissemination. Supporting such observations, the estimated risk for H5N1‐related human mortality was higher than previously reported. The need for multidimensional disease surveillance models, which may detect risks at higher levels than models that only measure one factor or outcome, was supported. To develop efficient surveillance systems, interactions should be captured, which include but exceed biological factors. This low‐cost and easily implementable model, if conducted over time, may identify focal instances where tailored policies may diminish both endemicity and the total adaptation of H5N1 to the human species.     

Infectious dose‐dependent accumulation of live highly pathogenic avian influenza H5N1 virus in chicken skeletal muscle—implications for public health

Highly pathogenic avian influenza viruses (HPAIV) of H5N1 subtype are a major global threat to poultry and public health. Export of poultry products, such as chicken and duck meat, is a known source for the cross‐boundary spread of HPAI H5N1 viruses. Humans get infected with HPAI H5N1 viruses either by close contact with infected poultry or through consumption of fresh/undercooked poultry meat. Skeletal muscle is the largest soft tissue in chicken that has been shown to contain virus during systemic HPAIV infection and supports productive virus infection. However, the time between infection of a chicken with H5N1 virus and presence of virus in muscle tissue is not yet known. Further, it is also not clear whether chicken infected with low doses of H5N1 virus that cause non‐fatal subclinical infections continue to accumulate virus in skeletal muscle. We investigated the amount and duration of virus detection in skeletal muscle of chicken experimentally infected with different doses (10², 10³ and 10⁴ EID₅₀) of a HPAI H5N1 virus. Influenza viral antigen could be detected as early as 6 hr after infection and live virus was recovered from 48 hr after infection. Notably, chicken infected with lower levels of HPAI H5N1 virus (i.e., 10² EID₅₀) did not die acutely, but continued to accumulate high levels of H5N1 virus in skeletal muscle until 6 days post‐infection. Our data suggest that there is a potential risk of human exposure to H5N1 virus through meat from clinically healthy chicken infected with a low dose of virus. Our results highlight the need to implement rigorous monitoring systems to screen poultry meat from H5N1 endemic countries to limit the global spread of H5N1 viruses.     

基于家禽产业链视角分析广东珠三角地区H7N9禽流感传播途径

珠三角地区H7N9禽流感传播途径具有复杂性和特殊性。为进一步明确传播途径,基于家禽产业链视角,在H7N9禽流感最为严重的广州市、深圳市、佛山市,采用分层抽样法选取有代表性且能反映整体情况的养殖场、批发市场、屠宰场、农贸市场,调查H7N9禽流感的动物防疫和个人防护情况。结果显示:养殖场的生物安全隔离仍不完善,存在活禽接触候鸟感染禽流感的风险;批发市场和屠宰场防疫水平高,人感染风险较低;农贸市场的动物防疫条件和个人防护不充分,易扩散病毒;最有可能的传播途径是与候鸟接触后携带病毒的活禽,通过"养殖—批发—零售"产业链蔓延。该结论在明确"禽传人"、"活禽市场环境暴露"观点上深化了产业链各环节间的传播路径。因此,珠三角地区H7N9禽流感的防控重点要加强养殖环节的生物安全隔离,并做好零售环节中活禽与人之间的防控。     

H10N8亚型禽流感病毒的研究进展

中国于2013年底首次发现H10N8亚型禽流感病毒（AIV）能感染人并致死的病例,而在此之前从未有过关于H10N8亚型病毒能感染人的报道,目前也未在其他国家监测到H10N8亚型AIV感染人的病例。与H7N9亚型AIV相似,H10N8亚型AIV在家禽中致病性很弱,可一旦感染人能表现出很强的致病性。感染了H10N8亚型AIV的患者病情恶化快、死亡率高、对人的健康危害很大,但至今尚无有效的防制手段。目前还不太清楚H10N8亚型AIV是通过何种途径传播给人的,今后H10N8亚型AIV是否会在人群中引发新的疫情暴发是人们普遍关心的问题。文章简要介绍了H10N8亚型AIV的特点及研究现状。     

Investigation of H7N2 avian influenza outbreaks in two broiler breeder flocks in Pennsylvania, 2001-02

An avian influenza (AI) outbreak occurred in meat-type chickens in central Pennsylvania from December 2001 to January 2002. Two broiler breeder flocks were initially infected almost simultaneously in early December. Avian influenza virus (AIV), H7N2 subtype, was isolated from the two premises in our laboratory. The H7N2 isolates were characterized as a low pathogenic strain at the National Veterinary Services Laboratories based on molecular sequencing of the virus hemagglutinin cleavage site and virus challenge studies in specific-pathogen-free leghorn chickens. However, clinical observations and pathologic findings indicated that this H7N2 virus appeared to be significantly pathogenic in meat-type chickens under field conditions. Follow-up investigation indicated that this H7N2 virus spread rapidly within each flock. Within 7 days of the recognized start of the outbreak, over 90% seroconversion was observed in the birds by the hemagglutination inhibition test. A diagnosis of AI was made within 24 hr of bird submission during this outbreak using a combination of virus detection by a same-day dot-enzyme-linked immunosorbent assay and virus isolation in embryonating chicken eggs. Follow-up investigation revealed that heavy virus shedding (90%-100% of birds shedding AIV) occurred between 4 and 7 days after disease onset, and a few birds (15%) continued to shed virus at 13 days post-disease onset, as detected by virus isolation on tracheal and cloacal swabs. AIV was not detected in or on eggs laid by the breeders during the testing phase of the outbreak. The two flocks were depopulated at 14 days after disease onset, and AIV was not detected on the two premises 23 days after depopulation.     

Antimicrobial‐resistant Enterobacteriaceae recovered from companion animal and livestock environments

Antimicrobial‐resistant bacteria represent an important concern impacting both veterinary medicine and public health. The rising prevalence of extended‐spectrum beta‐lactamase (ESBL), AmpC beta‐lactamase, carbapenemase (CRE) and fluoroquinolone‐resistant Enterobacteriaceae continually decreases the efficiency of clinically important antibiotics. Moreover, the potential for zoonotic transmission of antibiotic‐resistant enteric bacteria increases the risk to public health. Our objective was to estimate the prevalence of specific antibiotic‐resistant bacteria on human contact surfaces in various animal environments. Environmental surface samples were collected from companion animal shelters, private equine facilities, dairy farms, livestock auction markets and livestock areas of county fairs using electrostatic cloths. Samples were screened for Enterobacteriaceae expressing AmpC, ESBL, CRE or fluoroquinolone resistance using selective media. Livestock auction markets and county fairs had higher levels of bacteria expressing both cephalosporin and fluoroquinolone resistance than did equine, dairy, and companion animal environments. Equine facilities harboured more bacteria expressing cephalosporin resistance than companion animal shelters, but less fluoroquinolone resistance. The regular use of extended‐spectrum cephalosporins in livestock populations could account for the increased levels of cephalosporin resistance in livestock environments compared to companion animal and equine facilities. Human surfaces, as well as shared human and animal surfaces, were contaminated with resistant bacteria regardless of species environment. Detecting these bacteria on common human contact surfaces suggests that the environment can serve as a reservoir for the zoonotic transmission of antibiotic‐resistant bacteria and resistance genes. Identifying interventions to lower the prevalence of antibiotic‐resistant bacteria in animal environments will protect both animal and public health.     

Pig producers' perceptions of the Influenza Pandemic H1N1/09 outbreak and its effect on their biosecurity practices in Australia

The Influenza Pandemic (H1N1/09) virus was first reported in humans in Mexico in April 2009 and a pandemic level was declared on 11th of June 2009 by the World Health Organization (Chan, 2009; WHO, 2009a). Public misconceptions about the transmission of H1N1/09 were caused by the inadequate naming of the disease as 'swine influenza'. This cross-sectional study was conducted at the height of the outbreak in the Australian human population and before the virus was reported in the first piggery in Australia in July 2009 (OIE, 2009b; Holyoake et al., 2011). The aims of this study were to evaluate pig producers' perceptions about the virus and the outbreak financial impact and influence on on-farm biosecurity practices. A questionnaire was designed and posted to Australian Pork Limited (APL) members (n=460), obtaining responses from 182 producers (39.6%). Pig producers had good general knowledge on potential transmission pathways for H1N1/09 between people, with direct or close contact with a sick person perceived as the most likely pathways. Changes on biosecurity practices, such as asking visitors if they had recently been overseas (27.8%) and not allowing any visitor to inspect their pigs (18.3%), were reported among respondents. In addition, approximately 40% of producers asked their employees to notify flu like symptoms, consulted a veterinarian on H1N1/09 and visited websites to seek information on H1N1/09. A higher adoption of these practices was observed among large (>100 sows) than small herds. Only 2.9% of respondents reported a reduction in pig sales during the outbreak. However, approximately one third of producers reported being financially and emotionally stressed, 38.2% were distressed about the health of their pigs and 16.7% about their own health. The most important sources of information were APL (93%), veterinarians (89%) and the state Department of Primary Industries (DPI) (75%). The first two considered the most trusted sources of information. Television, radio and other farmers were considered more important sources of information by small herds and veterinarians by larger herds. Producers believed that the H1N1/09 outbreak was better managed by the pork industry (89.9%) than by the health authorities (58.8%), and the on-going communication with APL was the main strength of the outbreak management. Communication and extension programs in future outbreaks should consider the needs of all sectors of the pig industry to increase their effectiveness.     

Attribution of human infections with Shiga toxin‐producing Escherichia coli (STEC) to livestock sources and identification of source‐specific risk factors,The Netherlands (2010–2014)

Shiga toxin‐producing Escherichia coli (STEC) is a zoonotic pathogen of public health concern whose sources and transmission routes are difficult to trace. Using a combined source attribution and case–control analysis, we determined the relative contributions of four putative livestock sources (cattle, small ruminants, pigs, poultry) to human STEC infections and their associated dietary, animal contact, temporal and socio‐econo‐demographic risk factors in the Netherlands in 2010/2011–2014. Dutch source data were supplemented with those from other European countries with similar STEC epidemiology. Human STEC infections were attributed to sources using both the modified Dutch model (mDM) and the modified Hald model (mHM) supplied with the same O‐serotyping data. Cattle accounted for 48.6% (mDM) and 53.1% (mHM) of the 1,183 human cases attributed, followed by small ruminants (mDM: 23.5%; mHM: 25.4%), pigs (mDM: 12.5%; mHM: 5.7%) and poultry (mDM: 2.7%; mHM: 3.1%), whereas the sources of the remaining 12.8% of cases could not be attributed. Of the top five O‐serotypes infecting humans, O157, O26, O91 and O103 were mainly attributed to cattle (61%–75%) and O146 to small ruminants (71%–77%). Significant risk factors for human STEC infection as a whole were the consumption of beef, raw/undercooked meat or cured meat/cold cuts. For cattle‐attributed STEC infections, specific risk factors were consuming raw meat spreads and beef. Consuming raw/undercooked or minced meat were risk factors for STEC infections attributed to small ruminants. For STEC infections attributed to pigs, only consuming raw/undercooked meat was significant. Consuming minced meat, raw/undercooked meat or cured meat/cold cuts were associated with poultry‐attributed STEC infections. Consuming raw vegetables was protective for all STEC infections. We concluded that domestic ruminants account for approximately three‐quarters of reported human STEC infections, whereas pigs and poultry play a minor role and that risk factors for human STEC infection vary according to the attributed source.     

Detection of Antibodies to Alphaviruses and Discrimination between Antibodies to Eastern and Western Equine Encephalitis Viruses in Rabbit Sera using a Recombinant Antigen and Virus‐specific Monoclonal Antibodies

Three arthropod‐borne alphaviruses, western equine encephalitis viruses (WEEV), eastern equine encephalitis viruses (EEEV) and Venezuelan equine encephalitis viruses are the aetiological agents of a sometimes severe encephalomyelitis in equines and humans in the New World. With regard to the different ecology and epidemiology of these viruses, a method applied in serological screening should be able to distinguish between them as well as other related members of the genus Alphavirus in the American continent. However, this has been hampered in the past by (a) the close antigenic relationship between alphaviruses in traditional serological assays, especially in the routinely used haemagglutination‐inhibition, and (b) the need of biosafety level 3 facilities to grow the viral antigens. An epitope blocking assay using an EEEV glycoprotein E1‐expressing recombinant Sindbis virus and virus‐specific monoclonal antibodies (mAbs) binding to the E1 of EEEV (strain NJ/60) and the E1 of Sindbis virus was established using automated flow cytometry. The test was evaluated using sera of infected and vaccinated rabbits. A cut‐off value of 30% inhibition for antigenic complex‐specific seroconversion was found to be sufficient for the detection of the respective infection. By using three different mAbs in parallel, we were able to detect alphavirus genus‐, EEEV‐ and WEEV‐complex‐specific serum antibodies. As this test is based on the inhibition of binding of virus‐specific mAbs, sera of every origin other than mouse can be tested. Thus, this assay may prove useful in the serological screening of a variety of animal species during an outbreak investigation.