MINNEAPOLIS (WCCO) — Federal health officials say salmonella outbreaks linked to backyard chickens and ducks are affecting people across nation, including in Minnesota and Wisconsin.

The Centers for Disease Control says that since February the outbreaks have affected people in more than 40 states. Among those sickened were three people in Minnesota and four people in Wisconsin.

The CDC cautions that the number of people affected by the outbreaks is likely much greater than the current numbers show as few people seek treatment or get tested.

Health officials advise people to wash their hands after handling backyard poultry, refrain from snuggling the birds or eating around them.

Symptoms of salmonella include fever, stomach cramps and diarrhea. Most people recover without medical treatment, but some people — such as the elderly and young children — may experience more severe symptoms.

For more information on the outbreak, visit the CDC’s website.