West Nile Virus detected in Boston mosquito samples West Nile Virus was detected in mosquitoes in Jamaica Plain, Roslindale, Roxbury and West Roxbury.

West Nile virus has been detected in mosquitoes in Massachusetts for the first time this year, according to the Department of Public Health.

West Nile Virus is a mosquito-borne illness. People who are older than 50 years of age are at higher risk of developing serious symptoms, according to the Boston Public Health Commission.