By Lauren Victory

CHICAGO (CBS) — You can’t help but feel your heart melt when you look at the adorable face of a puppy – but this week, news emerged that some puppies may be infectious.

As CBS 2’s Lauren Victory reported Thursday afternoon, the Centers for Disease Control and Prevention warned that puppies are the source of germs that are spreading to people and making them sick.

“It’s a bacteria that, for lack of a better word, sets up camp in the GI tract,” explained Dr. Sara Lewis of the Animal Humane Society.

The CDC is warning of an outbreak of drug-resistant Campylobacter infections that are spread from puppies to people. They have identified 30 cases across 13 states.

At least four people have been hospitalized. Nobody has died, but Dr. William Schaffner of Vanderbilt University Medical Center said the symptoms are very unpleasant.

“It can cause an illness characterized by nausea, vomiting, abdominal cramps, diarrhea – which can sometimes be bloody – and it can last several days,” Schaffner said.

Most of the infections have been linked to puppies from pet stores, including the Petland chain, where several employees have gotten sick.

The CDC says if you are picking out a puppy, you should make sure it’s alert and playful. You also should take it to the vet for a checkup within the first few days

Doctors also suggest good hygiene for all pet owners.

“The best thing you can do to prevent getting Campylobacter is vigorous, frequent handwashing after you’ve played with the puppy,” Schaffner said.

And don’t get dogs lick your mouth. Puppy kisses can be cute, but they may also be hazardous to your health.

Petland says it has implemented all recommended protocols from health officials and is looking for the sources of infection.

Lauren Victory