Rat-bite fever (RBF) is a systemic bacterial illness caused by Streptobacillus moniliformis that can be acquired through the bite or scratch of a rodent or the ingestion of food or water contaminated with rat feces. Cases are rarely reported in the United States and the true incidence of disease is unknown. On August 7, 1996, a physician in a rural community reported a case of infection with S. moniliformis bacteremia in a 15-year-old boy to the New Mexico Department of Health. This report summarizes the results of the investigation of this case and indicates the need for ongoing surveillance for this illness.