West Nile Virus

The Town has received notification from the state Health & Homeland Alert Network (HHAN) this afternoon that Shelburne and Northfield have both had their first WNV positive mosquito samples.

As of the time of this email, West Nile Virus (WNV) risk levels have not changed. The risk level remains low in most towns and remains moderate in 5 of our towns. These are Monroe, Rowe, Charlemont, Heath and Leyden. Northfield and Shelburne and surrounding towns may also move up to moderate risk. Risk levels can be monitored on the arbovirus risk level maps on the state website, see link below. Moderate level of risk means that infection with WNV is likely or has already occurred. There have not been known human cases of WNV in our towns yet, but mosquitos trapped in Leyden, Northfield, Rowe and Shelburne have been found to be positive for WNV.

  • West Nile virus (WNV) is a mosquito-disease that can cause illness in humans and animals.
    • Humans: Roughly 80% of people infected with WNV do not develop any symptoms. Severe symptoms may occur in about 1 in 150 infected people.
    • Horses: Can develop severe neurological disease. Vaccines are available for horses as a preventative.
    • Birds: Amplifying hosts; they play a key role in spreading the virus to mosquitoes.
  • Symptoms in Humans
    • Mild cases: Fever, headache, body aches, rash, and fatigue.
    • Severe cases (about 1 in 150): Encephalitis or meningitis (swelling of the brain and/or spine), which can be life-threatening.
    • Higher risk: People over 50 or with weakened immune systems are more likely to develop serious illness.
  • Best Protection:
    • Avoid peak mosquito hours from dusk to dawn when mosquitoes are most active.
    • Use EPA-approved repellents.
    • Wear long sleeves and pants when possible.
    • Ensure window and door screens are intact to keep mosquitoes out.
    • Eliminate standing water by regularly emptying containers that collect water, such as flowerpots, bird baths, kiddie pools, tarps, and gutters.
  • Stay Informed:

Posted: to Town of Shelburne News on Wed, Aug 13, 2025
Updated: Wed, Aug 13, 2025