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Powassan Virus

​What is Powassan virus?                                                          
Powassan (POW) virus is a germ carried by some ticks. It can cause Powassan virus disease, a rare illness caused when infected ticks bite humans.  

Where is Powassan virus found?
Most cases of POW virus disease have occurred in the Northeast and Great Lakes regions of the United States.

How is Powassan virus spread?
POW virus is transmitted by the bite of an infected tick. POW virus is not transmitted directly from person-to-person.

What are the symptoms of Powassan virus disease?
Many people who become infected with POW virus do not develop any symptoms. When symptoms occur, they can include fever, headache, vomiting, weakness, confusion, loss of coordination, speech difficulties, and seizures. Symptoms usually start about 1 week to 1 month after a tick bites. POW virus can cause encephalitis (swelling of the brain) and meningitis (swelling of the membranes that surround the brain and spinal cord). Approximately half of survivors have permanent neurological symptoms, such as recurrent headaches, muscle wasting and memory problems and about 10% of POW virus encephalitis cases are fatal. 

How is Powassan virus disease treated?
There is no specific medicine to cure or treat POW virus disease. A healthcare provider may prescribe medications to relieve the symptoms of the illness. Severe cases will require hospitalization.

Is there a vaccine for Powassan virus?
No, there are no vaccines to prevent POW virus infection.

How can I prevent Powassan virus disease?
The best way to prevent POW virus infection is to prevent tick bites and avoid areas where ticks are likely to be found.  In general you can keep tick numbers low by reducing cover and shade, by keeping grass mowed, removing leaf litter and trimming shrubs and trees.  Other precautions to take:

  • Wear long sleeved shirts and long pants and tuck your pant legs into your socks. 
  • Light colored clothes can help you spot the ticks on your clothes before they reach your skin.
  • Stay to the middle of paths when in a heavily wooded area.
  • Use insect repellants approved by the Environmental Protection Agency (EPA).
  • Always check yourself and your children after being to a high risk area to find any ticks that may have attached.

What should I do if I find a tick on myself, my child, or my pet?
The longer a tick is attached to someone, the greater the chance it will be able to spread a disease-causing germ. That is why it is important to remove any ticks promptly using fine point tweezers:

  • The tick should not be squeezed or twisted, grasp it close to the skin and pull straight out with the steady pressure.  Other methods of such as using a match, petroleum jelly, or kerosene are not recommended.
  • Clean the skin around the bite with soap and water or a disinfectant.
  • Mark the date and location of the bite for future reference.
  • If you develop a rash or symptoms, see your healthcare provider.
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