Salmonellosis and arizonosis in the reptile collection at the National Zoological Park.

The prevalence of Salmonella and Arizona organisms in the reptile collection at the National Zoological Park was investigated. Culture of specimens from 311 reptiles, while live or at necropsy, yielded yielded 117 positive results, for an overall infection rate of 37%. Snakes had the highest rate, 55% (69 of 125); lizards had an intermediate rate, 36% (46 of 129); and turtles and tortoises had the lowest rate, 3% (2 of 63). Twenty-four serotypes of Salmonella enteritidis, 1 of S choleraesuis, and 39 of Arizona hinshawii were represented. While clinical illness was never directly attributed to infection with these organisms, pure cultures of Salmonella and Arizona were recovered at necropsy from some reptiles with gross and/or histologic lesions in the gastrointestinal tract, liver, spleen, and blood vessels. However, numerous other concurrent diseases and management problems were often considered the immediate cause of death, with Salmonella and Arizona being ready and significant opportunistic pathogens contributing to the demise of the reptiles.