Powassan Virus

Powassan Virus- is a tick borne encephalitis originally discovered in the town of Powassan, Ontario in 1958. In mouse studies it has been reported the virus can be transmitted within 15 minutes of an infected tick bite.

Ticks, such as Ixodes cookei (woodchuck ticks) and the black legged tick (Ixodes scapularis or deer tick) have been reported as the main carriers of the virus.

Symptoms- Powassan Virus symptoms can begin 1 to 4 weeks after a tick bite (1-2 weeks is typical). Symptoms can be mild to non-existent and sometimes begin with acute onset of fever. Muscle weakness, dizziness, headaches, vomiting, chills, fatigue, labored breathing, stiff neck, confusion, speech difficulties, memory loss, nausea, paralysis, encephalitis and meningitis.

Approximately 15% of those infected with the virus will experience severe symptoms, with 50% developing chronic neurological problems.

The disease usually progresses to viral encephalitis, or inflammation of the brain, which can cause severe brain damage. Approximately 10 percent of cases are fatal and an additional 50 percent suffer from long-term neurological impairment, such as complete paralysis of one side of the body.


Diagnosis- There are no commercially available tests on the market at this time. Blood can be sent to the Centers for Disease Control for testing.

UPDATE- As of March 2016 testing for the Powassan Virus will be available through Coppe Laboratories. [Please note- the CEO of Coppe Lab, Dr. Konstance Knox, is a member of the Infectious Diseases Society of America (IDSA).]

Coppe Laboratories®

CLIA Certified Lab

W229N1870 Westwood Drive

Waukesha, WI 53186

Fax (262)-574-0703 Office (262) 574-0726 Mobile 414-405-0931

Email- mjahn@coppehealth.com Website- www.coppelabs.com

Note- Lyme and other TBD testing is performed at this lab also. Lyme tests will not move forward to the Western Blot test if the 1st screening test is negative. (They cite CDC guidance for this out-dated procedure.) However, if requested by the physician they will do a Western Blot even if the screening test is negative.

Billing Info- http://www.coppelabs.com/for-patients-families/insurance-and-billing/


Treatment- There is currently no recommended treatment for Powassan Virus. Supportive therapy is recommended for the various symptoms. There is no vaccine available to prevent Powassan Virus.



Suspected Neuro-invasive Powassan Virus Infection in a Pediatric Patient

August 2020- Personal note on study below... It saddens me to read these kind of studies and to see what this poor child and her parents had to go through before getting a diagnosis and treatment. At the end, the study reports the child was lost to follow-up. My guess is she and her parents wanted nothing more to do with them (Department of Medicine, Harvard Medical School, Boston, Massachusetts, et. al.).

QUOTE- "The arbovirus MAC-ELISA IgM panel in serum (collected on day 4 of illness) was positive for POWV and Jamestown Canyon virus (JCV).

The POWV case fatality rate in adults is 10%–15%, with 50% of patients experiencing neurologic sequelae.

In conclusion, POWV is an emerging tick-borne pathogen capable of causing neuro-invasive disease. Clinicians in Lyme endemic regions should maintain a high degree of suspicion for POWV given the high mortality and long-term morbidity."

Link to Full Article Here





Last Updated- October 2020

Lucy Barnes

AfterTheBite@gmail.com