First Case Of West Nile Virus Detected in Boston This Year

Boston Public Health Commission encourages residents to take precautions as the risk of West Nile Virus in the city remains high.

Thursday, August 27, 2026 - Boston Public Health Commission (BPHC) today announced that a Boston resident has tested positive for West Nile Virus. The impacted resident is a man in his 60s and is the first human case of West Nile Virus in Boston this year. It is the third case of West Nile Virus in a Massachusetts resident so far this year. The Massachusetts Department of Public Health currently considers the West Nile Virus risk level in Boston "high" based on ongoing evidence of mosquitoes carrying the virus in the city. Over the last two months positive West Nile Virus mosquito test samples were found in several Boston neighborhoods. West Nile Virus is carried by mosquitoes and can be spread to humans through the bite of an infected mosquito.

You can reduce your risk of contracting West Nile Virus by using the following strategies to avoid mosquito bites.

• People age 50 and older and those who are immunocompromised should adjust outdoor activity to avoid peak mosquito hours (from dusk to dawn).
• Empty out and clean bird baths, unused flowerpots, and other vessels containing standing water at least twice per week to prevent mosquitoes from breeding regularly.
• Flip over unused kiddie pools and dispose of old tires, which are also known to collect rainwater that attracts mosquitoes for breeding.
• Clean out gutters and remove any debris or blockages regularly.
• Wear long sleeve clothing and high socks to keep mosquitoes away from your skin.
• Use EPA-approved insect repellents like DEET, oil of lemon eucalyptus, picaridin, or IR3535.
• Make sure screens in windows and doors fit properly and do not have any holes.

"West Nile Virus can result in very serious illness and may pose serious danger to older and more vulnerable members of our communities," said Dr. Bisola Ojikutu, Commissioner of Public Health for the City of Boston. "BPHC will continue to closely monitor this situation with our partners at the Massachusetts Department of Public Health. We encourage everyone to take precautions against mosquito borne illnesses, like using insect repellent, especially between dusk and dawn when mosquitoes are most active."

Most people who are infected with West Nile Virus do not experience any signs or symptoms of illness. In some cases, however, people will experience a headache, fever, nausea, vomiting, diarrhea, rash, and body aches which can last for a few days or several weeks. In most cases, individuals with mild symptoms recover on their own without needing medical assistance.

People who are older than 50 years of age or immunocompromised are at higher risk of developing severe illness as a result of West Nile Virus infection and may experience high fever and neurologic symptoms, like severe headache, confusion, lack of coordination, and muscle paralysis or weakness. If you or someone you know is experiencing these symptoms, contact a health care provider immediately. More information on WNV and other mosquito-borne illnesses is available on BPHC's website.

• Published by: Boston Public Health Commission