Powassan Virus - Tick Disease


    Image of a Groundhog tick and a Blacklegged tick

    Powassan is a potentially severe viral infection transmitted to people from the bite of an infected tick. It is a "cousin" of West Nile virus and is rare with only about 75 cases being reported in the United States over the past 10 years.   Most of the reported cases have occurred in the Northeast, including the Cape, and in the Great Lakes region.  A recent survey of ticks collected in several communities on Cape Cod have tested positive for this virus.

    The incubation period or the time from tick bite to emergence of symptoms for this virus range from one week to one month.   The signs and symptoms of infection can include fever, headache, vomiting, weakness, confusion, seizures, and memory loss.  In addition, long-term neurologic problems may occur.  

    Powassan is a viral disease, unlike Lyme which is caused by a bacteria, and because it is viral there is no specific treatment.  For many people there are no symptoms of infection.  But, people with severe Powassan illness often need to be hospitalized to receive respiratory support, intravenous fluids, or medications to reduce swelling in the brain.

    You can reduce your risk of becoming infected by avoiding bushy and wooded areas where ticks are common, using tick repellents (permethrin) on clothes or products containing DEET on skin, wearing long sleeves and pants, and doing thorough tick checks after spending time outdoors.  Pets should also be checked for ticks frequently and spraying perimeters of yards may prove helpful.

    It's very important that you contact your healthcare provider if you think you or a family member may have Powassan disease. 


    CDC - Powassan virus