Rat-Bite Fever

Three cases of rat-bite fever, resulting from the bite of laboratory rats, were observed in a 6-month period. In two cases, Streptobacillus moniliformis was obtained from blood culture. Extracellular spiral organisms, presumably Spirillum minus, were observed on peripheral blood smear in the third case. All cases responded promptly to penicillin therapy. The occurrence of three cases in 6 months suggests that this disease may be commoner than is currently appreciated. Extreme care must be taken when handling laboratory rats.