Powassan Virus Infection

Powassan virus infection is an uncommon infection caused by a type of virus called a flavivirus.

Powassan virus is spread to people from a bite from an infected tick, mostly by a blacklegged tick. It can take as little as 15 minutes for an attached tick to feed on a person’s blood to pass the virus onto them.

Symptoms usually begin to show up within one week to one month after getting bitten by an infected tick. Most people who have Powassan virus infection do not have symptoms however, people who do get symptoms may have:

  • Fever
  • Headaches
  • Nausea
  • Vomiting
  • Low energy or feel weaker than usual
  • Body aches and pains

People with symptoms might start to feel better but then develop more serious symptoms like confusion, difficulty speaking, paralysis, seizures, or a coma state. Fifty percent of the people who survive severe Powassan virus infection have long-term health issues such as repeated headaches, low muscle strength, and memory problems.

People who live in, work in, travel to, or visit areas that are at-risk for ticks have a higher risk of getting Powassan virus infection.

If you think you might be infected with Powassan virus, speak to your health care provider about getting assessed and ways to relieve your symptoms.

The best way to prevent Powassan virus infection is to avoid tick bites.

How to avoid tick bites:

  • Wear long pants and long sleeves.
  • Light coloured clothing may make ticks easier to spot.
  • Apply insect repellent approved by Health Canada (Personal Insect repellents – Canada.ca), following the manufacturer’s instructions
  • Walk closer to the centre of trails avoiding brushy areas that may extend out on the trail edges.
  • After spending time outdoors in wooded or bushy areas, shower to remove ticks before they become attached.
  • Carefully check your full body and head for attached ticks.
  • If you find a tick on your body, remove it as soon as possible.
  • Remember to also check your children and pets for ticks.

Powassan virus infection is diagnosed by a blood test, spinal fluid or other body sample to check if you have the virus or have been exposed to it.

There is currently no medication to treat Powassan virus infection. Speak to your health care provider about ways to help relieve your symptoms.