A 5-year-old girl was admitted to hospital with fever, headache and nausea. Her C-reactive protein raised from less than 11 mg/l to 65 mg/l and she developed a maculopapular, petechial rash, especially pronounced on the soles and palms. After incubation for 3 days, Streptobacillus moniliformis was found in all blood cultures that had been taken. Some weeks before her admission, the girl had been playing with her grandmother's pet rats, which later had died from an unknown disease. There was no history of rat bite. Her condition improved rapidly after treatment with penicillin and chloramphenicol, and she was discharged from hospital after 10 days without sequelae.