As the U.S. anticipates the annual surge in mosquito populations, pork producers are urged to implement robust control strategies to reduce mosquito populations near swine farms and minimize potential production impacts. Changes in environmental conditions, specifically during high rainfall seasons, may result in increased mosquito populations that can be a risk for emerging disease and other swine production challenges. Through global disease monitoring by the Swine Health Information Center, heightened awareness for mosquito control stems from the recent 2025 re-emergence of Japanese encephalitis virus in Australia, a stark reminder of the potential impact of this mosquito-borne pathogen.
In February 2025, JEV was reported at two piggeries in southern Queensland, Australia, marking the first detections of the virus in AU commercial swine since July 2022. With no cases detected in piggeries during 2023 or 2024, this re-incursion of JEV into Australian piggeries requires close monitoring. Recent detections in mosquito populations in Goondiwindi, Inglewood, and Monto, as well as in mosquito and feral pig populations in New South Wales, have raised concerns about further potential spread of JEV, particularly with wet season conditions increasing mosquito activity.
The U.S. is currently negative for JEV, a mosquito-borne virus which has waterbirds as a natural reservoir host but is capable of infecting pigs, humans and horses. As a transboundary disease risk for U.S. introduction, JEV is transmitted through the bite of infected mosquitos and can cause reproductive failure, delayed farrowing, stillbirths, mummified fetuses, abortions and weak piglets in swine breeding herds. In December 2024, SHIC, along with the Foundation for Food & Agriculture Research, funded six research projects to enhance U.S. prevention, preparedness, mitigation and response capabilities for JEV.
Click here to see more...