Clinical And Epidemiological Studies of Japanese B Encephalitis

Report 1: Epidemiological and clinical statistics of patients with Japanese B Encephalitis in Kyoto City

Abstract

Four hundred forty nine patients with Japanese B encephalitis admitted in Kyoto Municipal Hospital since 1947 to 1962 have been observed from the epideminlogical and clinical stand point of view. The results were concluded as follows.
1) The highest incidence of this disease was observed in 1951 and 1956, and the lowest was in 1947 and 1950.
2) No significant difference was observed, in the number of patients between male and female however, a tendency was noticed that more male patients were observed in infant group and more female ones in aged group.
3) It was evident that the number of patients under 15 years old have been decreasing since 1958.
4) The onset of epidemic of the disease has started at the begining of August in most of the years and in these years more patients were obresved.
5) A higher indiednce of this disease was observed in the south and the east part of Kyoto City.
6) The mortality of this disease was 34.7 percent in this City (159 patients out of 449 patients died of this disease). It was higher in female and aged group.
7) Onset with other symptoms than fever was observed in 13.8 percent of the patients.
8) The highest body temperature was 40 to 41 centigrades in most cases. A parallelism seemed to exist between body temperature and letality.
9) Disturbance of consciousness was observed in 81.2 percent of the patients. Over half of the patients with coma were fatal. The prognosis of the patients with eye symptoms was poor.
10) A higher mortality was observed among the patients with lower cerebrospinal fluid pressure and less cell count in the cerebrospinal fluid.
11) Sequelae were obserued in about one fourth of the whole patients.