Chickens can carry bacteria such as Salmonella and viral infections such as avian influenza, and urban regulation of backyard poultry ownership can help to reduce the risk of human infection, the researchers say in an article in the journal Public Health Reports.
Jessica Leibler, a BU assistant professor of environmental health, and colleagues say local ordinances should incorporate specifications on a range of health measures, including manure management, slaughter and disposal of sick poultry, veterinary care, consumer education, and registration of households with poultry.
“The reintegration of live poultry into the urban environment poses risks to human health due to zoonotic disease transmission from poultry to humans,” the authors say. “Noncommercial contact with poultry has been associated with numerous multistate salmonella outbreaks in recent years and poses risks for transmission of other bacterial and viral pathogens.
“The local nature of poultry regulation poses challenges for systematically managing infectious disease risk from backyard poultry, and many US urban ordinances do not fully address the infectious disease risks to humans associated with this practice.”
Leibler and colleagues from BU’s College of Health & Rehabilitation Sciences: Sargent College and College of Arts & Sciences and from George Washington University assessed local ordinances in the 150 most populous US cities for regulations related to noncommercial poultry ownership, using online resources and communications with government officials. They also performed a literature review, using publicly available data sources, to identify human infectious disease outbreaks caused by contact with backyard poultry since 1990.
Annually, an estimated 1.4 million people in the US are infected with nontyphoidal salmonella serovars. Exposure to noncommercial live chickens and eggs has been the source of 45 documented salmonella outbreaks since 1991, with 1,581 documented illnesses, 221 hospitalizations, and five deaths, the authors say.
Despite these risks, many backyard chicken owners are unaware of infectious disease risks from poultry contact and do not engage in appropriate hygienic behaviors, Leibler and colleagues say. A 2010 US Department of Agriculture study suggested that more than 50 percent of urban poultry owners were unaware that live poultry contact poses infectious disease risks for humans, and nearly 25 percent reported not washing hands after handling live poultry.
Of the cities reviewed, 93 percent permit poultry in some capacity. Most urban poultry ordinances share common characteristics focused on reducing nuisances to neighbors. But many of the ordinances do not address the pathways of transmission relevant to poultry-to-human transmission of pathogens, such as manure management, the authors found.
Among the study’s recommendations are: requiring owners to compost poultry manure in sealed containers; prohibiting slaughter at the home; requiring veterinary care in the event of bird illness and reporting of rapid die-offs within the flock to city officials through a website or hotline; disposing of dead birds properly; and requiring owners to participate in educational programs, such as online modules, about hygiene and sanitation in conjunction with the permitting and renewal process.
A version of this article was originally published in the School of Public Health website.
Source: Boston University