Prevalence of Ranavirus in Virginia Turtles as Detected by Tail-Clip Sampling versus Oral-Cloacal Swabbing

Ranaviruses are emerging infectious diseases that infect amphibians, fish, and reptiles. Several cases of morbidity and mortality in captive and natural populations of reptiles have been attributed to ranaviruses, but research in this taxon has been limited. We used oral-cloacal swabs and tail clips to survey two species, Chrysemys picta picta (Eastern Painted Turtles) and Sternotherus odoratus (Common Musk Turtles), in three water bodies in central Virginia to determine if ranaviruses were present. Prevalence of ranavirus in C. p. picta ranged from 4.8–31.6% at the three sites. Ranavirus was not detected in S. odoratus, but only oral-cloacal swabs were used in this species because of the cornified tail tip. While tail-tip tissues from all three study sites indicated presence of ranavirus in C. p. picta, no oral-cloacal swabs from these same turtles tested positive. We therefore suggest that oral-cloacal swabbing may yield false negatives when ranavirus is present in turtles, and that tissue sampling may be more appropriate for monitoring ranavirus in turtles.