ATLANTA, June 23 (Our Illinois Times) — Powassan virus is still rare in the United States, but federal health officials say the tick-borne infection can be transmitted quickly and can lead to serious brain disease, making tick checks and bite prevention especially important in outdoor seasons.
The Centers for Disease Control and Prevention says Powassan is spread by the bite of an infected tick and is reported most often in the Northeast and Great Lakes regions. The agency says cases have increased in recent years, though it remains uncommon.
CDC guidance says the illness can start with fever, headache, vomiting and weakness. In severe cases, the infection can progress to encephalitis or meningitis and cause confusion, loss of coordination, speech problems, seizures and paralysis.
The CDC says there are no vaccines to prevent Powassan virus disease and no medicines to treat it. The agency says older adults, children and immunocompromised people are at higher risk of developing neuroinvasive disease.
A Defense Centers for Public Health–Aberdeen overview says studies show some ticks can transmit the virus in as little as 15 minutes of feeding. A peer-reviewed case report in PMC said human transmission can occur within hours of tick attachment and cited experimental evidence of transmission as quickly as 15 minutes.
That fast transmission differs from many other tick-borne diseases and means a tick bite may be enough to spread the virus before a person notices it. The CDC says Powassan can also rarely be transmitted through blood transfusion.
The CDC says about 10% of patients with Powassan virus neuroinvasive disease die and about half of survivors have long-lasting neurologic deficits. Defense public-health officials say approximately half of patients who survive the encephalitis form of the disease suffer permanent brain damage.
