Backyard chickensThe backyard poultry debate continues in many areas. It raised is head again in Guelph recently, with more city government debate about how far you have to keep your backyard chickens from your neighbours. There are a number of issues to consider, like potential for spread of zoonotic bacteria (e.g. Salmonella), avian flu, noise, smell and attracting other critters (e.g. coyotes).

A recent study in Zoonoses and Public Health (Kauber et al 2016) engaged owners of backyard chickens in Seattle to look at their level of knowledge of Salmonella, and practices that might influence Salmonella exposure risk.

Here are some highlights from the study:

  • Owners of the 50 studied backyard flocks were predominantly white (94%), female (74%) and well educated. 36% had a 4-year college degree and 54% had a graduate degree.
  • 90% of flocks were comprised of 8 or fewer birds.
  • Only one person had chicks on the premises at the time of the study. Those were kept inside.
  • 80% of people knew Salmonella was a bacterium, all but one knew people can get salmonellosis.

They also asked people about their infection control practices. You always have to take results like this with a grain of salt because if people know what they should be doing, there’s a chance they’ll give you that answer rather than what they actually do. They also collected video footage of people caring for their birds. This would likely provide more accurate information but still with some potential for people changing their behaviour because they knew they were being watched (the Hawthorne effect).

  • Two thirds of people said they don’t wash poultry-related items in the house or in areas where food is prepared. (The flip side is that 1/3 of people do this, and that is considered a high risk practice).
  • Three quarters rarely (10%) or never (66%) let their birds inside the house (a more obvious way to track bacteria and other bugs into the house).
  • One quarter had close contact with the birds, such as kissing them (to each their own, I guess).
  • Over one half allowed children less than 5 years of age to have contact with chickens, especially chicks. (This is getting into higher risk territory too, since contact with chicks is recurrently associated with salmonellosis outbreaks, particularly in kids).
  • In the videos, young kids were seen petting chickens, playing barefoot in the chicken area and entering the house with shoes worn in the chicken area. (I’m not a germaphobe and think environmental exposures are good for kids. This is to the extreme of that, given the known Salmonella risk. Outside and dirty… good. Outside and dirty with chickens… not so much).
  • People often touched their mouth or face while caring for the birds.
  • When comparing the video and survey results, over 50% of people who said they don’t have close contact with birds were observed snuggling with birds or touching their face.

What does this mean?

It’s hard to say. We really don’t know what the Salmonella risk is to owners of these small backyard flocks. The risk is probably greatest when people buy chicks, since lots of outbreaks have occurred from newborn chicks (both because they often carry Salmonella and because there is often closer contact with them). The risk to neighbours is also unclear, and presumably varies a lot with things like climate, rainfall and the contour of the land (e.g. a sloping lawn that sends chicken-poop-tea into the neighbouring lawn every time it rains).

There are some good aspects of having backyard chickens and some concerns, including disease and other issues. This study helps with one piece of the puzzle, and points out some potential areas to address.

The paper’s conclusions aren’t surprising but are logical: The data from this survey reveal that backyard poultry owners are aware of the association between Salmonella and poultry, but that they do not consistently perform risk-reducing husbandry and hygiene practices as recommended by CDC and the State department of health to help prevent infection with Salmonella. There is a need for better education to effectively communicate the risk of potential for zoonotic disease transmission and provide recommendations for husbandry and hygiene practices.