The relationship of infection rate of Japanese encephalitis in mosquito vectors to the incidence of encephalitis in Thailand from 1992 to 1994

Supon Paosriwong*
Apiwat Tawatsin*
Usavadee Thavara*
Chitti Chansang*
Prakong Phan-Urai*

Affiliations :
      *National Institute of Health, Department of Medical Sciences

Source:
      Journal of Health Science 1998; 7(2): 241-246

Language:
      Thai with English abstract

Abstract:
      The occurrence of Encephalitis is related to several factors. The infection rate in vector mosquitoes which are Culex tritaeniorhynchus, Culex gelidus,   and Culex fuscocephala,   may be one variable to predict the epidemiological trend of Encephalitis. The objective of this study was to determine whether there was the relationship between JE virus infection rate in mosquitoes and the incidence of Encephalitis cases in 6 provinces of Thailand: Uttaradit, Chiangrai, Chumphon, Suratthani, Khonkaen and Ayutthaya. Mosquito samples were collected every month for three years (1992-1994). The JE virus antigen was detected by ELISA technique. In Uttaradit, Chiangrai, Suratthani, Khonkaen and Ayutthaya, direct relations were reported with correlation coefficients (r) of 0.32, 0.07, 0.15, 0.11, and 0.42 respectively, whereas in Chumphon there was an inverse correlation with a correlation coefficient (r) of -0.04.