Centers for Disease Control and Prevention (CDC), several states, and the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (USDA-APHIS) investigated a multistate outbreak of drug-resistant Campylobacter infections. Epidemiologic and laboratory evidence indicated that contact with puppies sold through Petland stores was a likely source of this outbreak.
A total of 113 people with laboratory-confirmed infections or symptoms consistent with Campylobacter infection were linked to this outbreak. Illnesses were reported from 17 states. Illnesses started on dates ranging from January 12, 2016 to January 7, 2018. Ill people ranged in age from less than 1 year to 86, with a median age of 27. Sixty-three percent of ill people were female. Of 103 people with available information, 23 (22%) were hospitalized. No deaths were reported. Whole genome sequencing (WGS) showed that isolates from people infected with Campylobacter were closely related genetically, meaning that people in this outbreak were more likely to share a common source of infection.
In interviews, ill people answered questions about the foods they ate and any animal contact in the week before they became ill. Ninety-nine percent of people reported contact with a puppy in the week before illness started, and 87% reported they had contact with a puppy from Petland stores or had contact with a person who became sick after contact with a puppy from a Petland store. Twenty-five ill people worked at Petland stores.
During the investigation, officials collected samples from pet store puppies for laboratory testing and identified the outbreak strain of Campylobacter in the samples. WGS showed that the Campylobacter isolates from sick people in this outbreak and isolates from pet store puppies were closely related genetically, providing additional evidence that people got sick from contact with pet store puppies.
Campylobacter bacteria isolated from clinical samples from people sickened in this outbreak were resistant to commonly recommended, first-line antibiotics. The 12 isolates tested by standard methods were resistant to azithromycin, ciprofloxacin, clindamycin, erythromycin, nalidixic acid, telithromycin, and tetracycline. In addition, 10 were resistant to gentamicin, and 2 were resistant to florfenicol.