Horses owners in Butte County should vaccinate their animals against West Nile virus, health officials warn, as mosquitoes are expected to proliferate in the Camp Fire burn area after a particularly rainy season. West Nile virus is a potentially serious, sometimes fatal disease that can be transmitted to animals and people through the bite of an infected mosquito, according to the U.S. Centers for Disease Control and Prevention. Horses face increased risk for the virus because they generally are outdoors at dawn and dusk, when mosquito activity is highest, according to a news release Wednes...