Salmonellosis is an important zoonotic disease that is associated with many animal species, including reptiles. The sale of pet turtles in the United States has been banned for decades after it was discovered that these animals posed a human health risk. Studies consistently document the presence of Salmonella in captive pet reptiles. The CDC estimates that 90% of these animals carry Salmonella and that 74,000 cases of reptile-associated salmonellosis occur annually in the United States. In this study, 94 wild-caught turtles (6 species native to North Carolina) were cultured for Salmonella. Salmonella was not isolated from any of the samples. Lack of isolation may have been due to inadequate collection of fecal matter, or wild turtles may not be shedders or carriers of Salmonella species. Funded in part by the Merck Merial Veterinary Scholars Program
COMMENTARY: This is the second study that found 0% prevalence of Salmonella in free-ranging reptiles.1 According to this study's authors, there are 2 major hypotheses of why captive reptiles shed this pathogen. The first hypothesis is that they are natural carriers of the organisms, which are shed in a stressful environment, such as captivity. The other hypothesis is that they are not natural carriers of Salmonella species but acquire the infection in captivity. Between the study abstracted here and Richards and colleagues' study,1 there were 176 wild reptiles that were either caught or brought to a wildlife facility, making it highly improbable that none of them were "stressed." Thus, the study raises more questions than it answers. Furthermore, living in a captive environment is clearly stressful; however, it is hard to believe that life as a wild reptile is "stress free." Everyone is mindful of proper hygiene when handling reptiles because of all of the press they have gotten as carriers and shedders of Salmonella spp but don't forget that in May 2005 the CDC issued a warning that pet hamsters, mice, and other pet rodents were another unrecognized source of exposure.
1. Absence of detectable Salmonella cloacal shedding in free ranging reptiles on admission to the Wildlife Center of Virginia. Richards JM, Brown JD, Kelly TR, et al. J ZOO ANIM MED; 35:562-563, 2004.
Prevalence of Salmonella spp in cloacal, fecal, and gastrointestinal mucosal samples from wild North American turtles. Saelinger CA, Lewbart GA, Christian LS, Lemons CL. JAVMA 229:266-267, 2006.