Man hospitalized for weeks with tick-borne illness. What is Powassan virus?

A New Hampshire man has been hospitalized for weeks after contracting a rare but serious tick-borne illness called Powassan virus, according to multiple local reports.

After feeling worn down from a tick bite, the 66-year-old was admitted to Concord Hospital for about two weeks before being transferred to Massachusetts General Hospital for more intensive care, sources close to the patient told WMUR and the Concord Monitor.

USA TODAY has reached out to the New Hampshire Department of Health and Human Services for comment.

What is Powassan virus?

Powassan virus is spread to people through a bite from an infected tick. Although the virus is rare, according to the CDC, the number of reported cases of people sick from the virus has increased in recent years. It does not spread through coughing, sneezing or touching, but in rare cases, it has spread person-to-person through a blood transfusion.

Most cases of Powassan virus in the US are in the Northeast and Great Lakes regions and are found from late spring through mid-fall, when ticks are most active.

Powassan virus is named after Powassan, Ontario, in Canada, where it was first discovered in 1958, according to the Minnesota Department of Health.

What are the symptoms of Powassan virus?

Initial symptoms can include fever, headache, vomiting and weakness, according to the CDC. In some cases, Powassan virus can cause severe disease, including encephalitis, an infection of the brain, or meningitis, an infection of membranes around the brain and spinal cord.

Someone with severe disease can experience confusion, loss of coordination, difficulty speaking and seizures, and the CDC says approximately one in 10 people with severe disease die.

Approximately half the people with severe disease can have long-term health problems, including recurring headaches, loss of muscle mass and strength, and memory problems.

There are no vaccines that can prevent Powassan virus or medicines to treat the disease. The CDC recommends that people avoid ticks to reduce risk of infection.

How to spot ticks and what you need to know

Ticks are often found in grassy, brushy or wooded areas, and can also live on animals. They can also be found in yards or neighborhoods, the CDC says.

In order to avoid contact with ticks, avoid wooded and brushy areas with high grass and leaf litter, and walk in the center of trails. The CDC also recommends treating clothing and gear with products containing 0.5% permethrin, and to use Environmental Protection Agency-registered insect repellents.

After you come in from outdoors, the CDC recommends checking your clothing for ticks and to remove any that are found. You can kill them by tumble drying clothes in a dryer on high heat for 10 minutes. If you need to wash clothes, use hot water first.

You should also conduct a full body check after coming in from outdoors, in which you check the following areas:

Under the arms

In and around the ears

Inside the belly button

Back of the knees

In and around the hair

Between the legs

Around the waist