Infectious Disease Epidemiology Program
Vector-borne Diseases
Powassan Encephalitis Q&A
- Question 1. What is Powassan Encephalitis?
- Question 2. Who gets Powassan encephalitis?
- Question 3. How is Powassan spread?
- Question 4. What are the signs of Powassan infection?
- Question 5. When do the signs of Powassan first appear?
- Question 6. What are the treatment methods?
- Question 7. What are the prevention methods?
- Question 8. How do I properly remove a tick?
- Question 9. How do I obtain information on tick identification?
Question 1. What is Powassan Encephalitis?
A. Powassan encephalitis
is a serious and rare tick-borne illness caused by the Powassan virus. In Maine, the Powassan
virus is spread by the woodchuck tick.
Question 2. Who gets Powassan encephalitis?
A. Anyone can get
infected with the Powassan virus. The majority of cases occur in adults who spend time outdoors
in areas where ticks are common during the months of April through October.
Q3. How is Powassan spread?
A. Powassan is spread by the bite
of a tick that already has the germ. Powassan does not spread from person to person.
Q4. What are the signs of Powassan infection?
A. Early signs
of Powassan usually include headache, fever, nausea, vomiting, stiff neck, and sleepiness.
In later stages, signs such as respiratory distress, tremors, confusion, seizures, coma, paralysis,
and sometimes even death can occur.
Q5. When do the signs of Powassan first appear?
A.Signs generally
are seen about 4-18 days after the tick bite.
Q6. What are the treatment methods?
A. There is currently no
effective treatment for Powassan. If you have Powassan, your doctor will have you kept at the
hospital so that you can receive supportive care.
Q7. What are the prevention methods?
A. To prevent Powassan
and other tick-borne illnesses, the best protection is to avoid contact with ticks. If you
are working, playing, or relaxing in areas that may have ticks you should do the following:
- Wear light colored clothing (spot ticks easier) with long sleeve shirts and pants
- Create an extra "no tick" zone by tucking your pants into your socks and you shirt into your pants
- Use insect repellent (with DEET) on your skin and apply permethrin (kills ticks on contact)
to your clothes. For information on other recommended repellents, click on the following
link: http://www.cdc.gov/ncidod/dvbid/westnile/RepellentUpdates.htm

- Check your clothing and skin carefully after being outdoors in likely tick infested areas & remove ticks promptly
- Wash area of any possible tick bites thoroughly with soap and water, apply an antiseptic to area of the bite
- Mark on a calendar the date that you were bitten, then watch yourself for signs of powassan or any changes in your personal health every day for the next two weeks
- Keep your lawn mowed, cut overgrown brush, and clear away leaf litter from your home
- Inspect any pets daily and remove any ticks found
Q8. How do I properly remove a tick?
A. Using tweezers, you should
grab the tick at its mouth and using firm steady pressure you should pull the tick out. Do
not yank or squish the tick because it may have harmful bodily fluids. Also, do not use petroleum
jelly, hot matches, nail polish remover or any other substance to remove the tick. Using those
items could increase the risk of an infection.
Q9. How do I obtain information on tick identification?
A. You
can have a tick identified by sending it to the Maine Medical Center Lyme Research Lab. For
specific instructions on how to submit a tick please go to the Maine Medical Center Lyme Research
Lab website at: www.mmcri.org/lyme/submit.html