Serological Epizootiology of Japanese Encephalitis Virus Infection in Horses in Japan

DOI
  • ANDO Yasumasa
    Tochigi Branch Laboratory, Equine Health Laboratory, Japan Racing Association

Bibliographic Information

Other Title
  • 日本における馬の日本脳炎の疫学的研究

Search this article

Description

Japanese encephalitis (JE) attacks man and swine in every summer, although its morbidity has decreased remarkedly in recent years. The racehorses belonging to the Japan Racing Association have been free from clinical infection of JE since several years ago. They have received preventive inoculation with inactivated JE virus vaccine (JE vaccine) regularly every year. Accordingly, HI antibody titer has been found in horses. Does this antibody serve for the prevention of JE virus infection? To settle these problems, the present survey was conducted with the following results. (1) Young horses less than 4 years of age showed an indistinct antibody response to JE vaccine, which had been inoculated every year. (2) The rate of possession of HI antibody was compared between racehorses in the Tokyo area and those in the Osaka area. It was higher in the latter than in the former, at the end of the epizootic period of JE. (3) HI antibody titer was estimated on blood samples collected from experimental horses at regular intervals during a five year period of 1972 to 1976. It was reasonable to find horses in which the antibody appeared and increased in titer by natural infection in autumn of all the years, except 1976. This result indicates that these horses were involved in inapparent infection, regardless of age and history of vaccination.

Journal

Details 詳細情報について

Report a problem

Back to top