Possible pathogenicity of Japanese encephalitis virus in newly hatched domestic ducklings.

Japanese encephalitis virus (JEV) is a zoonotic flavivirus that is transmitted by mosquitoes and vertebrate-amplifying hosts, including birds. Domestic ducks are susceptible to JEV infection and develop various levels of viremia. We tested the pathogenicities of seven JEV strains in newly hatched domestic ducklings. All inoculated ducklings showed stunted growth. Two JEV strains caused notable mortalities of 12.7% and 31.7%, respectively, highlighting that some emerged JEV strains may thus be pathogenic in newly hatched domestic ducklings.