Japanese encephalitis virus (JEV) is a disease transmitted by mosquitoes that infects pigs, horses and humans. In swine, this virus causes reproductive failure, delayed farrowing, stillbirths, mummified fetuses and weak piglets. Historically, JEV has been primarily maintained in endemic Southeast Asia and Pacific Island nations. In 2022, an outbreak of JEV genotype IV spread rapidly across new geographic regions of Australia, impacting roughly 60% of the commercial swine industry, with an estimated cost of $250,000 (USD) per 1,000 sows. While this virus has not been detected in the U.S., its recent spread warrants the need for a close investigation of this disease and its potential for incursion and establishment in the U.S.
The Swine Health Information Center and the Foundation for Food & Agriculture Research awarded in 2024 a total of $1.3 million to six projects through its jointly funded Japanese Encephalitis Virus (JEV) Research Program. The program invests in critical research to prevent JEV incursion, ensure rapid detection of JEV if introduced to the U.S., inform stakeholder response, mitigate production losses on the sow farm, identify effective control measures and develop clear messaging to consumers on the safety of pork. Research priorities include transmission and epidemiology, mosquito control, diagnostics, communication, surveillance, compatible cases, challenge models, vaccines, cross-protection, competent vectors, the role of wildlife, novel hosts and viral sequencing.