Japanese encephalitis virus surveillance in the Taipei area, Taiwan in 1978.

ABSTRACT

Attempts were made to isolate Japanese encephalitis virus from mosquitoes collected with three light traps operated twice a week at three sentinel pigpens in the Taipei area from May to Oct. 1978. A total of 6,549 mosquitoes trapped alive were processed in 283 pools. Suspensions were inoculated into Aedes albopictus cell cultures and into suckling mice. A total of 19 JE virus isolates were made; 12 from pools of Cx. tritaeniorhynchus, 6 from Cx. annulus and one from Cx. quinquefaciatus. Sindbis virus was isolated for the first time in Taiwan from a pool of Cx. tritaeniorhynchus. More isolates were made from mosquito cell cultures (20) than by mouse inoculation (6). Positive isolations of JE virus by mouse inoculation were all from the mosquitoes obtained during an 11 day period from 20 to 30 June 1978 when all six sentinel pigs were viremic. This study shows the decided advantage of the use of mosquito-cell cultures over that of mice.