If you planned on buying a dog for a loved one this Christmas, maybe you should reconsider. As CBS News reports, pet store puppies are being blamed for making humans sick in 13 states across the U.S.

A report from the Centers for Disease Control and Prevention (CDC) published on December 17 reveals that 30 people have contracted a drug-resistant strain of the bacteria Campylobacter jejuni. Campylobacter can cause fever, abdominal cramps, and diarrhea, and of the 30 people affected by the illness between January 6 and November 10, 2019, four were sent to the hospital. There have been no deaths linked to the bacterial outbreak so far.

Epidemiologic and laboratory evidence, as well as interviews with patients, traced the new strain of Campylobacter back to pet store puppies. The CDC interviewed 24 of the 30 people who reported the illness, and out of that group, 21 reported contact with puppies before getting sick. In 15 out of the 21 cases, the interactions took place at a pet store, and in 12 of those 15 cases, the store was a location of the national chain Petland.

The Campylobacter outbreak has spread to regions across the country. Minnesota has recorded the most reports of any state with six. Ohio is close behind with five, as is Nevada with four.

If you work at a pet store or already have a puppy at home, there's no need to quarantine yourself until this latest wave of illnesses has passed. Instead, the CDC recommends taking a few precautions to limit your chance of infection. Washing your hands frequently and thoroughly is the best way to protect yourself, especially after making a contact with puppies, their food, or their messes. When petting dogs, don't let them lick your face—especially around your mouth—and stop them from licking any open wounds. And if you get a new puppy for the holidays, make sure to bring them to the vet for a check-up within a few days.

[h/t CBS News]