A horse, mosquito, and snake walked into a bar. The bartender looks up and says, "Is this some kind of joke?" Turns out, the bartender knows those three animals shouldn’t be fraternizing because he read a recent article by Thomas Unnasch, PhD, proving snakes can harbor Eastern equine encephalitis virus (EEEV) and could play an important role in transmitting this deadly virus.

Like the West Nile virus, mosquitoes become infected with EEEV after a blood meal from an infected bird. If that mosquito then feeds off a horse, the EEEV can be transmitted to the horse.

"Certain areas in the northeastern United States are ‘hot spots’ for EEEV," explained Unnasch, a researcher from the Global Health Infectious Disease Research Program, Department of Global Health at the University of South Florida, in Tampa. "Because there are no mosquitoes in those areas of the U.S. in the winter and few birds, it wasn’t obvious how the virus over-wintered in those areas."

He added, "Previous research found that certain mosquito species feed off of reptiles as well as birds and horses, suggesting that hibernating snakes infected with the EEEV via mosquitoes could explain how the virus survives the winter