Ball Python Nidovirus: a Candidate Etiologic Agent for Severe Respiratory Disease in Python regius

Stenglein, Mark D.; Jacobson, Elliott R.; Wozniak, Edward J.; Wellehan, James F. X.; Kincaid, Anne; Gordon, Marcus; Porter, Brian F.; Baumgartner, Wes; Stahl, Scott; Kelley, Karen; Towner, Jonathan S.; DeRisi, Joseph L.

Current standards in herpetoculture encourage disease transmission and may foster evolution of increased pathogen virulence. Captive snake breeding operations typically operate at high stocking densities, and breeders commonly attend trade shows, where animals from different sources are juxtaposed. In addition, animals from geographically and ecologically diverse areas are commonly imported and mixed with minimal quarantine. These practices increase pathogen exposure and lower barriers to transmission. The outcome is evident in the case of farmed turtles, which typically have very high Salmonella carriage rates, in contrast to the low prevalence in wild turtle populations (66) (67) (68) . It is also possible that these practices select for increased virulence, as has been the case for feline calicivirus (FCV), which has independently evolved multiple times from a pathogen that causes a relatively benign upper respiratory disease to one that causes hemorrhagic disease with high mortality (69) . This increase in FCV virulence has been documented only in high-density environments, such as shelters. Surveillance of wild ball pythons in Africa will shed light on whether a similar phenomenon has occurred here. Further investigation of the pathogens of reptiles and improved biosecurity practices and disease surveillance of the herpetoculture industry are indicated.