In addition to WNV, Eastern equine encephalitis (EEE) has also been detected in mosquitoes in Massachusetts this year. Clothing Can Help Reduce Mosquito Bites. Water troughs provide excellent mosquito breeding habitats and should be flushed out to reduce mosquitoes near paddock areas. Horse owners should keep horses in indoor stalls at night to reduce their risk of exposure to mosquitoes. Owners should also speak with their veterinarian about mosquito repellents approved for use in animals and vaccinations to prevent West Nile virus (WNV) and EEE.