WORCESTER—A human case of West Nile Virus (WNV) has been detected in Worcester, prompting the Central Massachusetts Mosquito Control Project (CMMCP) to schedule truck-mounted pesticide spraying in the area where the case was reported. The spraying is set for Thursday, Sept. 18, beginning after 7:30 p.m., weather permitting, according to a city release.
The city’s WNV risk level remains at moderate. A map of the areas to be sprayed is available online, officials said.
Residents who wish to exclude their property from the wide-area pesticide application may do so by following the opt-out instructions on the Massachusetts Department of Agricultural Resources website.
Along with spraying, CMMCP provides other mosquito control services such as ditch maintenance and abandoned pool treatments. Service request forms are available at cmmcp.org or by phone at 508-393-3055. The agency also publishes information about the products used in its Integrated Pest Management program.
Residents in affected neighborhoods will receive notifications about spraying through email, text, and social media. Those who want to receive alerts are encouraged to register with ALERTWorcester and ensure their contact information is up to date. Additional alerts will be issued if more mosquito-borne illness cases are detected.
Health officials advised residents to take precautions if their area is being sprayed: close windows, keep pets inside, and remain indoors during the application and for 15–20 minutes afterward. Vegetables from home gardens should be washed before eating.
The pesticide being used is considered safe for people and pets, though individuals with chemical sensitivities are advised to consult their physician.
To reduce mosquito bites and the risk of infection, residents are urged to follow the “5 Ds”: dress in long sleeves and pants when possible, use DEET repellent, be cautious at dawn and dusk, drain standing water weekly, and make use of insect-repellent clothing or treated fabrics.
Most people infected with WNV will not experience symptoms, though some may develop fever or flu-like illness. In rare cases, infection can be severe. People over the age of 50 are at higher risk for serious complications.
The Worcester Division of Public Health is working with state officials to monitor mosquito-borne illness. Five human cases of WNV have been reported in Massachusetts so far in 2025.
More information, including statewide test results for WNV and Eastern equine encephalitis, is available at mass.gov/mosquito-borne-diseases or by calling the Massachusetts Department of Public Health Division of Epidemiology at 617-983-6800.
