2002年に報告された日本脳炎症例5例の臨床的検討

Abstract

We discussed the clinical features of 5 Japanese encephalitis (JE) cases which we experienced in 2002. Today there are few opportunities for a clinician to see JE patients. Until the 1950s, the number of JE patients was more than 2000 in Japan, but the annual cases of JE are decreasing remarkably due to the extermination of mosquitoes, thorough vaccination and improvement of environmental sanitation. However, even today the disease still has a high fatality rate. In fact 4 in 5 cases we experienced had poor prognosis and one of them resulted in death despite the relatively early diagnosis. It shows the difficulty of diagnosis and treatment. When we see elderly patients with high fever, headache, and impaired consciousness in late summer and autumn, the important thing is to recognize the possibility of JE. Moreover it turned out that brain MRI and detecting serologic JE virus antibodies was very helpful for diagnosis and treatment. Nowadays we clinicians tend to consider JE as a disease of the past in Japan, however, this experience taught us that it is necessary for us to study JE again and to continue educating the public about it.