@article{oai:nagasaki-u.repo.nii.ac.jp:00024697, author = {林, 薫 and 三舟, 求真人 and 七条, 明久}, issue = {2}, journal = {熱帯医学 Tropical medicine}, month = {Aug}, note = {The presence of Japanese encephalitis (JE) vius in mosquitoes infected experimentally could be demonstrated on the 3-5 day after infection by the intracerebral inoculation into mice and at the same time, the viral antigen in the mosquitoes midgut could be detcted as well by the fluorsecent antibody technique. In the salivary gland of mosquitoes infected, the viral antigen was found on the 11-13 day after infection. In pigs infected experimentally with JE virus, on the other hand, the viremia appeared on the 2-3 day and not on the 6-7 day after infection. The hemagglutination-inhibition (HI) antibody in pig sera, sensitive to 2-mercaptoethanol, showed rapid rise subsequently. Referring to these process of JE virus infection in both mosquitoes and pigs, the starting time of infection in mosquitoes in early stage of epidemic may be estimated by counting backwad 3-12 days from the date of the first isolation of JE virus from mosquitoes caught in fields, and the starting time of infection in pigs to retrace at least 5 days before the date of detection of HI antibody in pig sera. Using such a method, it was possible that the starting time of infection in mosquitoes in early stage of epidemic during the period from 1965 to 1969 appeared usually 4 or 37 days earlier than that in pigs. In the case of 1965, the JE virus infection in mosquitoes in the earliest stage of epidemic could be retraced upto May 18 or 27 by counting backward from the May 30 when the first isolation of JE virus from mosquitoes caught in the fields was made. In the latter part of that month, the prevalence of newly emarged mosquitoes showed a peak in population. It was presumed that the first stage of JE virus amplification would occurr in the presence of susceptible pigs. Same phenomenon were observed both in 1966 and 1967. In 1968, however, the first isolation of JE virus from mosquitoes was made on July 22. It was about one month later than in previous two years. The starting time of infection in mosquitoes in that year,on counted backward, was on July 19 or 11. The prevalence of newly emarged mosquitoes, on the other hand, had reduced markedly in the middle part of that month. Consequently, it was conceivably possible that the amplification of JE virus could not be expected efficiently under that circumstances, eventhough there were plenty susceptible pigs there., 熱帯医学 Tropical medicine 12(2). p51-63, 1970}, pages = {51--63}, title = {日本脳炎ウイルス撒布の解析と早春における蚊及び豚の推定感染}, volume = {12}, year = {1970} }