BARNSTABLE — The Massachusetts Department of Public Health (MDPH) has confirmed that West Nile virus (WNV) has been detected in a mosquito sample collected in the Town of Barnstable.
According to the Barnstable Public Health Division, a sample of 15 mosquitoes collected in Cotuit on July 21, 2026, tested positive for West Nile virus.
WNV is most commonly spread to people through the bite of an infected mosquito. The mosquitoes that carry the virus are common throughout Massachusetts and can be found in both urban and rural areas.
While anyone can become infected with West Nile virus, people over the age of 50 are at greater risk for developing more serious illness.
Barnstable County Mosquito Control crews are responding by treating catch basins and containers holding standing water in areas near where the positive mosquito sample was identified. The Town of Barnstable Public Health Division says it will continue working with MDPH and other agencies to monitor the situation.
Health officials are reminding residents and visitors to take precautions to reduce their risk of mosquito bites, especially during the peak mosquito activity hours from dusk through dawn.
Recommended steps include:
• Avoid peak mosquito hours: Consider limiting outdoor activities during the evening and early morning when many mosquitoes are most active.
• Cover exposed skin: Wearing long sleeves, long pants, and socks can help reduce bites, even during warmer weather.
• Use insect repellent: Products containing DEET, permethrin, picaridin, IR3535, or oil of lemon eucalyptus (PMD) can help prevent mosquito bites when used according to label directions.
• Remove standing water: Residents should empty or remove containers that collect water, including flowerpots, birdbaths, wading pools, and clogged gutters, where mosquitoes can breed.
• Check screens: Repair or replace window and door screens to help keep mosquitoes outdoors.
Health officials also remind residents that mosquito activity can occur anywhere, and taking simple precautions can help protect individuals and their families.
More information about West Nile virus, including current and historical virus activity in Massachusetts, is available through the Massachusetts Department of Public Health’s Arbovirus Update page.
Residents can also find general mosquito and West Nile virus information through the Massachusetts Department of Public Health.
