抄録
A Japanese encephalitis hemagglutination-inhibition (HI) antibody survey was conducted on a total of 1, 763 pigs produced, raised, and shipped in three areas, A, C, and I, or Aikawa, Choyo, and Ichinomiya, during the whole year 1965. There were 737 positive pigs (34.8%). The positive rate was 34.8%, 69.7%, and 44.1 % in areas A, C, and I, respectively.
A 100 % positive conversion rate was seen in area C over a period from July to September, in area A in August, and in area I in September and October. The rate of cases showing a titer 1: 640 or higher to the whole positive cases was high in area C. The frequency of occurrence of the encephalitis among human inhabitants was also high in this area, indicating a high degree of contamination.
Flrea C has hot springs which may provide favorable conditions for the occurrence of mosquitoes.
