A rare tick-borne virus has been reported in New York, prompting health officials to remind residents that ticks can remain a health threat even as temperatures begin to cool.

A Madison County adult man tested positive for Powassan virus, a disease that is uncommon but can cause serious neurological illness, according to the Madison County Health Department. The man is recovering at home.

Powassan virus is primarily spread through the bite of an infected tick. Most U.S. cases occur in the Northeast and Great Lakes regions, particularly from late spring through mid-fall when ticks are most active.

Unlike Lyme disease, which is caused by bacteria, Powassan is caused by a virus. There are currently no vaccines or specific medicines available to prevent or treat the infection, making protection against tick bites especially important.

What Is Powassan Virus?

Powassan virus is a tick-borne flavivirus that can infect people after the bite of an infected tick. Blacklegged or deer ticks are among the ticks that can transmit the virus, and the same type of tick can also spread Lyme disease and other infections.

Not everyone infected with Powassan develops symptoms. When illness does occur, symptoms can initially resemble other viral infections and may include fever, headache, vomiting and general weakness.

The CDC says the incubation period ranges from one to five weeks, while Madison County health officials say symptoms typically begin one to four weeks after an infected tick bite.

Powassan Can Cause Brain and Spinal Cord Inflammation

The greatest concern with Powassan is its potential to cause neuroinvasive disease.

In some patients, the virus can lead to encephalitis, or inflammation of the brain, or meningitis, which involves inflammation of the tissues surrounding the brain and spinal cord. Severe symptoms can include confusion, loss of coordination, difficulty speaking and seizures.

Older adults, children and people with weakened immune systems have a higher risk of developing severe disease, although anyone infected can potentially develop neurological complications.

Severe Powassan infection can be life-threatening. The CDC estimates that approximately one in 10 people with severe Powassan illness die, while about half of those who survive severe illness experience long-term health problems, which may include recurring headaches, weakness or memory problems.

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How Quickly Can a Tick Spread Powassan?

One reason tick prevention matters is that Powassan may be transmitted relatively quickly after a tick attaches.

Madison County health officials warn that Powassan virus can potentially be transmitted soon after an infected tick attaches, making prompt tick removal particularly important.

The CDC recommends avoiding tick bites in the first place by using insect repellent, wearing long sleeves and trousers, avoiding brushy or wooded areas where ticks are common and checking the body carefully after spending time outdoors.

If a tick is found attached to the skin, it should be removed promptly using fine-tipped tweezers. The tick should be grasped as close to the skin as possible and pulled upward with steady pressure. Madison County health officials also recommend showering soon after coming indoors and checking children and pets for ticks.

There Is No Specific Treatment for Powassan

There is currently no specific antiviral treatment for Powassan virus and no vaccine available for humans. Treatment is supportive, meaning doctors manage the symptoms and complications while the body fights the infection.

People with severe disease may require hospital care, particularly if they develop encephalitis or meningitis. Treatment is supportive and may include fluids, symptom management and support for breathing or complications such as brain swelling.

Because early symptoms can be nonspecific, a history of possible tick exposure can be important when doctors evaluate someone with fever or neurological symptoms. Anyone who develops concerning symptoms after a possible tick bite should tell their healthcare provider about the exposure.

The New York case serves as a reminder that tick exposure does not necessarily end when summer does. Preventing bites and checking for ticks after spending time outdoors remain among the most important ways to reduce the risk of Powassan and other tick-borne infections.

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