Pet store puppies are the likely source of drug-resistant infection in people known as Campylobacter jejuni in the United States between 2011 and 2020, according to a new study.

Campylobacter is the most common cause of bacterial diarrhea in the U.S., with an estimated 1.5 million people becoming infected each year. These are often related to poultry, though they may be from other foods as well. Common symptoms are (often bloody) diarrhea, fever, abdominal pain, nausea, and vomiting. About 20% of reported infections are from foreign travel. Some people will experience arthritis or Guillain-Barré syndrome, a type of paralysis.

Antibiotic-resistant Campylobacter has been a growing problem since the FDA approved the use of Ciprofloxacin in poultry flocks in 1995.

Six people were infected after contact with puppies were reported to the Florida Department of Health in 2017, causing the CDC and other state health departments to study the drug-resistant strains. .

"One of the things that really caught our attention is when we realized that these isolates from these puppies were related to isolates from human patients in Ohio…the strain of bacteria that they were carrying was the same,” Louise K. François Watkins, MD, of the CDC, one of the co-authors of the study, said,

Co-author Mark E. Laughlin, a veterinary medical officer at the CDC, says they are not recommending screening of puppies for Campylobacter because it is so commonly carried.

Meghan Davis, DVM, of Johns Hopkins Bloomberg School of Public Health, who was not involved with the study, agreed. In an interview she said, “Increased veterinary oversight of antibiotic use in this context and attention to the factors that may drive such uses are important considerations for public health authorities and the industry.”

The study, she says, “highlights an important gap in our surveillance systems for companion animals, including dogs and cats. Outside of certain notifiable diseases or investigations like this one linked to human or animal disease, most surveillance for diseases like Campylobacter focus only on people or food-producing animals.”

Both Watkins and Laughlin said it’s important for doctors to be aware of the drug- resistant Campylobacter and the association with puppies.

Watkins said, “Unfortunately, these strains are resistant not only to the drugs that we report on in our paper on our panel, but they're resistant to even some of the options beyond the ones that we normally think of. So, it's a pretty ugly strain of bacteria.”

Davis’ advice for the public is, “As the COVID-19 pandemic has highlighted, pets are important to our health and wellbeing. At the same time, pets and people can be exposed to and get sick from a wide variety of pathogens, including Campylobacter, so precautions are warranted. In addition to washing hands after playing with pets, people can avoid face contact, use barriers (like gloves or plastic bags) when handling wastes, and keep contact minimal if the pet or they themselves are sick.”