Seroepidemiological evidence for the presence of Japanese encephalitis virus infection in ducks, chickens, and pigs, Bali-Indonesia

Background: The presence of various animals, such as: ducks, chickens and pigs in households increases the potential risks of zoonosis from animal to human. One of the diseases is Japanese encephalitis (JE). The seroepidemiological studies on the presence JE among animals especially those raised in household is very important for emerging and reemerging disease control program. Ducks, chickens and pigs have long been considered as carrier and even the amplifier hosts of Japanese encephalitis virus (JEV) replication. The presence of the animal hosts and mosquitoes as vector could result in transmission of the JEV to humans. Methods: A seroepidemiological study of the presence of Japanese encephalitis virus (JEV) was conducted by collecting sera and detecting the antibody against JEV in ducks, chickens and pigs in Bali. As pig is the amplifying animal of JEV, comparison JEV antibody between ducks reared in households with pig nearby and with no pig were also determined the presence of antibody against JEV was examined by using indirect enzyme-linked immunosorbent assay (ELISA). The serum samples with over cut off value (COV) of optical density were considered as those containing Ab against JEV. Results: Antibody against JEV was demonstrated in ducks (20.6%), chickens (36.7%) and pigs (32.2%) evaluated in this study. Moreover, there was no significant difference (p>0.05) in the prevalence of antibody against JEV in ducks kept closely with pigs compared to the antibody in the ducks reared without pigs around. Conclusion: This study convinced that antibody against JEV is found in ducks, chickens and pigs in Bali. Indicating that these animals was infected or previously infected by the virus.