Multistate outbreak of Salmonella infections associated with small turtle exposure, 2007-2008

Abstract

Objective: Turtle-associated salmonellosis was increasingly recognized in the United States during the 1960s, leading to a federal ban in 1975 on the sale of turtles <4 inches in carapace length (small turtles). Although sporadic reports of turtle-associated Salmonella are frequent, outbreaks are rare. In September 2007, several patients with Salmonella enterica serotype Paratyphi B var Java infections reported recent turtle exposure. We conducted an investigation to determine the source and extent of the infections.

Patients and methods: Patients with Salmonella Paratyphi B var Java infections with a specific pulsed-field gel electrophoresis pattern (outbreak strain) and illness onset between May 2007 and January 2008, were compared with healthy controls. Reptile exposure and awareness of a Salmonella-reptile link were assessed. Turtle size and purchase information were collected.

Results: We identified 107 patients with outbreak-strain infections. The median patient age was 7 years; 33% were hospitalized. Forty-seven (60%) of 78 patients interviewed reported exposure to turtles during the week before illness; 41 (87%) were small turtles, and 16 (34%) were purchased in a retail pet store. In the case-control study, 72% of 25 patients reported turtle exposure during the week before illness compared with 4% of 45 controls (matched odds ratio [mOR]: 40.9 [95% confidence interval (CI): 6.9-unbounded]). Seven (32%) of 22 patients versus 11 (28%) of 39 controls reported knowledge of a link between reptile exposure and Salmonella infection (mOR: 1.3 [95% CI: 0.4-4.6]).

Conclusions: We observed a strong association between turtle exposure and Salmonella infections in this outbreak. Small turtles continue to be sold and pose a health risk, especially to children; many people remain unaware of the link between Salmonella infection and reptile contact.