Mosquito Sample Tests Positive For West Nile Virus; Suffolk's 1st In 2025

SUFFOLK COUNTY, NY — One mosquito sample has tested positive for West Nile virus — the first confirmed case in Suffolk County in 2025, Suffolk County Health Commissioner Dr. Gregson Pigott announced Friday.

The sample, of the Culex pipiens-restuans species, was collected in Nesconset on July 1.

Four mosquito samples have tested positive for Jamestown Canyon virus. The mosquito samples were of the Aedes cantator species. They were collected in June and on July 3, from Southold.

West Nile Virus

West Nile virus, first detected in birds and mosquito samples in Suffolk County in 1999 and again each year thereafter, is transmitted to humans by the bite of an infected mosquito. Suffolk County reported 21 human cases of West Nile virus in 2024 and 5 in 2023. Nine people have died from West Nile virus since 2000.

It is estimated that 20 percent of those who become infected will develop clinically noticeable symptoms of West Nile virus disease. Mild symptoms may include fever, headache and body aches, skin rash and swollen lymph glands. More severe symptoms include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis.

West Nile virus can be fatal. Residents who experience symptoms are advised to visit their healthcare providers. While there is no specific treatment for West Nile virus, patients may be offered supportive therapy as needed.

People who are most at risk for severe infection include those over 50 years of age and those with chronic illness or compromised immune systems. Suffolk County residents are urged to take precautions to avoid being bitten by mosquitoes during mosquito season, which extends from June 1 through Nov. 1.

Jamestown Canyon Virus

Jamestown Canyon virus is spread to humans by the bite of an infected mosquito. Fever, headache and fatigue are common symptoms of Jamestown Canyon virus. Symptoms of severe disease may include stiff neck, confusion, loss of coordination, difficulty speaking, or seizures. There are no vaccines to prevent the virus and treatment is supportive care.

Though Suffolk County has had no reported cases of Jamestown Canyon virus, this virus has been isolated in mosquito samples in 2008, 2017, 2022, and 2023. Residents are advised to take precautions to avoid mosquito bites. More information on Jamestown Canyon virus can be found on the Centers for Disease Control and Prevention website.

"The finding of Jamestown Canyon virus or West Nile virus in mosquito samples indicates the presence of that virus in the area," Pigott said in a news release. "While there is no cause for alarm, we advise residents to take precautions and cooperate with us in our efforts to reduce exposure to mosquito-borne diseases."

Pigott offered the following tips to avoid mosquito bites:

• Minimize outdoor activities between dusk and dawn.
• Wear shoes and socks, long pants and long-sleeved shirts when mosquitoes are active.
• Use mosquito repellent, following label directions carefully.
• Make sure all windows and doors have screens, and that all screens are in good repair.
• Keep mosquitoes from laying eggs inside and outside of your home. Once a week, empty and scrub, turn over, cover, or throw out containers that hold water, such as vases, pet water bowls, flowerpot saucers, discarded tires, buckets, pool covers, birdbaths, trash cans and rain barrels.
• Download a copy of Suffolk County’s informational brochure “Get the Buzz on Mosquito Protection,” available in English and Spanish, and share it with your community.

Dead birds may indicate the presence of West Nile virus in the area. To report dead birds, call the Bureau of Public Health Protection at 631-852-5999 from 9 a.m. to 4 p.m., Monday through Friday.

Residents are encouraged to take a photograph of any bird in question.

To report mosquito problems or stagnant pools of water, call the Department of Public Works’ Vector Control Division at 631-852-4270.

For further information on West Nile virus, visit the Department of Health Services’ website.