Disease Name

Powassan Disease

Vector Information

Powassan disease is a viral infection most commonly transmitted through the bite of an infected blacklegged tick. Powassan is preventable, if simple steps are taken to reduce exposure to ticks.

The disease is rare with approximately 75 cases over the past 10 years, but there is evidence incidence is increasing. There is no treatment for this disease. About 50% of cases are hospitalized to receive supportive care. This disease can be fatal regardless of any supportive treatment. Symptoms of Powassan disease include fever, headache, vomiting, weakness, confusion, seizures, and memory loss. Long-term neurologic problems such as muscle wasting and memory problems may also occur. In severe cases, the virus attacks the central nervous system and can cause encephalitis and meningitis. Symptom onset typically occurs one week to one month post tick bite, however, many people do not develop any symptoms. Diagnosis of Powassan infections is based on symptoms and laboratory test of blood or spinal fluid. Powassan disease is not transmittable between people. 

Vector Transmitters