West Nile Virus Found In Melrose Mosquito Sample

The illness is most commonly spread through the bite of an infected mosquito.

By Benjamin Pierce, Patch Staff

Aug 14, 2026 4:34 PM EDT

MELROSE, MA — West Nile virus has been detected in mosquitoes collected in Melrose, prompting local health officials to remind residents to take precautions against mosquito bites.

The Massachusetts State Public Health Lab confirmed that a mosquito sample collected in Melrose on Wednesday, Aug. 12, tested positive for West Nile virus. There have been no human cases of the virus reported in Massachusetts so far this year. With mosquito populations expected to remain active into September and beyond, health officials are urging residents to reduce their risk of mosquito bites.

Most people infected with West Nile virus do not develop symptoms, though about 1 in 5 develop a fever along with symptoms that can include headaches, body aches, joint pain, vomiting, diarrhea, or a rash. Most recover completely, but fatigue and weakness can persist for weeks or months. About 1 in 150 infected people develop a severe illness affecting the central nervous system, including meningitis or encephalitis. People over the age of 60 and those with certain medical conditions are at greater risk of severe illness, which in some cases can result in lasting effects or death.

The Melrose Health and Human Services Department is encouraging residents to use insect repellents with an EPA-registered ingredient such as DEET, picaridin, or permethrin and to carefully follow product instructions, particularly when using repellents on children. Residents should also wear long sleeves, long pants, and socks when practical and consider limiting outdoor activities between dusk and dawn, when mosquitoes are most active. Mosquito netting can be used on baby carriages and playpens.

Homeowners can help reduce mosquito breeding by eliminating standing water around their properties, including water that collects in containers, clogged gutters, and pool covers. Swimming pools should be kept clean and properly chlorinated, while window and door screens should be tightly fitted and repaired if damaged.

The Massachusetts Department of Public Health continues to conduct seasonal surveillance for both West Nile virus and Eastern equine encephalitis, updating community risk levels throughout the summer as positive mosquito samples are identified. Residents can monitor the latest mosquito testing results and community risk levels through the state's online arbovirus surveillance maps.