Togavirus infection in rural Thailand.

Hemagglutination inhibition tests for antibody against chikungunya virus and the four dengue viruses were performed on a rural Thai village population. The 50% and 90% prevalence indices fell at about ages 3 and 15 for dengue virus exposure. This is considerably earlier exposure than comparable urban populations. The prevalence of chikungunya virus antibody was also age related with 50% prevalence at about age 45.