New virus transmission route discovered in pigs.

Japanese Encephalitis (JE) virus causes serious inflammation of the brain in people and fertility problems in pigs. Mosquitoes were previously the only known transmission route. However, the virus can also be spread from pig to pig by direct contact, and this could enable it to circulate in pigs during the mosquito-free winter season. The JE virus is the main cause of serious encephalitis in people in Asia. The virus is found in large parts of Southeast Asia and is now also widespread in India. It circulates between birds and mosquitoes and between pigs and mosquitoes, and is passed to humans through mosquito bites. In children in particular, infection can lead to acute encephalitis and permanent impairment or even death. In pigs, the main effect of the virus alongside fever and encephalitis is fertility problems. The virus is closely related to the West Nile, Zika and dengue viruses. All are transmitted by mosquitoes and are flaviviruses, which cause serious illness in humans and animals. Previously, the only known transmission route for JE viruses was mosquitoes. A team of researchers from the Institute of Virology and Immunology and the University Bern at the Vetsuisse Faculty led by Dr. Meret Ricklin and Prof Artur Summerfield have now shown that JE viruses can also be passed directly from pig to pig. The study has just been published in the journal "Nature Communications."