Multistate Outbreak of Salmonella Enteritidis Infections Linked to Pet Guinea Pigs

The Centers for Disease Control and Prevention (CDC), several states, and the U.S. Department of Agriculture Animal and Plant Health Inspection Service are investigating a multistate outbreak of Salmonella Enteritidis infections.

The CDC began investigating in December 2017 when CDC PulseNet identified a cluster of three Salmonella Enteritidis infections that whole genome sequencing showed were closely related genetically.

A review of the PulseNet database identified six more closely related illnesses dating back to 2015. These illnesses were added to the outbreak case count.

Nine people infected with the outbreak strain of Salmonella Enteritidis have been reported from eight states.
Illnesses started on dates ranging from July 17, 2015 to December 15, 2017. One person was hospitalized, and no deaths were reported.

Epidemiologic and laboratory evidence indicates that contact with pet guinea pigs is the likely source of this multistate outbreak.
Four of the seven people interviewed reported contact with a guinea pig or its habitat in the week before getting sick.

The outbreak strain of Salmonella was identified in a sample collected from an ill person’s pet guinea pig in Vermont. Whole genome sequencing showed that Salmonella bacteria isolated from sick people and the guinea pig were closely related genetically. This result provides more evidence that people in this outbreak got sick from contact with pet guinea pigs.

Whole genome sequencing did not identify predicted antibiotic resistance in 11 of 13 isolates analyzed (9 ill people and 4 guinea pigs). One isolate from a sick person and one isolate from a guinea pig contained genes for resistance to streptomycin, sulfisoxazole, and trimethoprim-sulfamethoxazole. Testing of outbreak isolates using standard antibiotic susceptibility testing by CDC’s National Antimicrobial Resistance Monitoring System laboratory confirmed these results.

This outbreak is a reminder that pet rodents such as guinea pigs, regardless of where they are purchased or adopted, can carry Salmonella bacteria even when they look healthy and clean.

Follow CDC’s tips to keep you and your pet safe and healthy:
- Pick the right pet. Pet rodents are not recommended as pets for children younger than 5 years, and should not be kept in childcare centers.
- Always wash your hands after touching, feeding, or caring for pet rodents or cleaning their habitats.

Source: CDC