The Atlanta-based Centers for Disease Control and Prevention is investigating a salmonella outbreak that has sickened 163 people in 43 states, including nine people in Georgia.

The outbreak is linked to chickens and ducks kept in backyards, the CDC said in its report posted online Thursday.

Those sickened range in age from less than a year old to 87, and 58% are female. Nearly a third (34 people) have been hospitalized.

According to the CDC, the actual number is probably higher, because many people recover without medical care and, therefore, are not tested. But of the 92 people the CDC interviewed, 81 reported having contact with backyard poultry before getting ill.

Infection can be prevented, however. The CDC recommends the following safety tips:

Always wash your hands with soap and water right after touching backyard poultry or anything in the area where they live and roam. Adults should supervise handwashing by young children. Use hand sanitizer if soap and water are not readily available.

Don’t let backyard poultry inside the house, especially in areas where food or drink is prepared, served, or stored.

Set aside a pair of shoes to wear while taking care of poultry and keep those shoes outside the house.

Children younger than 5, adults over 65, and people with weakened immune systems shouldn’t handle or touch chicks, ducklings, or other poultry.

Don’t eat or drink where poultry live or roam.

Don’t kiss backyard poultry or snuggle them and then touch your face or mouth.

Stay outdoors when cleaning any equipment or materials used to raise or care for poultry, such as cages, or feed or water containers.

For a complete list of recommendations, visit the Healthy Pets, Healthy People website section on backyard poultry.