Murine typhus infected in Oku-etsu area, Fukui Prefecture

Abstract

A 15-year-old girl, high school student, became febrile (38-39 degrees C) with chills, sore throat and cough on April 20, 1994. Until the onset, she was healthy and she had been camping with her classmates in a wooded mountainous area in Oku-etsu, Fukui Prefecture. She consulted a local clinic on April 21 and bacampicillin was initially administered and then changed to cefaclor on April 23. However, high body temperature continued and a maclopapular rash appeared on her face on April 24 and gradually spread to her anterior chest and back. Blood examination showed a WBC count of 2,200/microliter, and she was admitted to our hospital on April 25. On admission, peripheral blood data showed leukocytopenia (WBC 2,300/microliter) with 5% atypical lymphocytes. Titers of anti-Rickettsia typhi serum antibodies (IgM, -G) were elevated (1:80, 1:640) and she was diagnosed as having murine typhus. On the second hospital day, 200 mg of minocycline (MINO) was administered per os and her body temperature fell to within the normal limits on the third hospital day. On the 7th hospital day, the skin rash disappeared and she was discharged. Altogether, 320 high school students went camping with this patient. Among them, approximately 30 students had similar symptoms and signs as this case and had been diagnosed suspected viral infection. Twelve students of the 30 were admitted to other hospitals. It was considered that this case was part of an outbreak of murine typhus in the Oku-etsu area, Fukui Prefecture, but no further investigation was performed. Murine typhus is usually a benign disease that is controllable by the administration of MINO. In rare cases, infection can worsen to multiorganic failure, severe complications have been reported in 1-4% of cases, and death has been reported in less than 3%. Recently, it has also been reported that MINO not only has an antibiotic effect, but also play acts as a cytokine modulator in patients with rickettsial infection. Thus, in febrile patients in whom uncommon Rickettsia infection is suspected, serological test for murine typhus should be examined and the immediate administration of MINO is important.