Rare deadly tick-borne virus that has no cure is spreading through the US
A potentially deadly tick-borne virus with no cure is spreading in the US, with case numbers reaching historic highs.
The Powassan virus was first discovered in a young boy in 1958, when the four-year-old developed symptoms medical experts couldn’t explain.
In 2025, 76 Americans were diagnosed with the virus, the highest number on record and up from an average of seven diagnoses per year.
The virus – which is spread by infected woodchuck or deer ticks – has continued to spread more quickly than usual, leaving experts worried.
Most cases are concentrated in the Northeast United States, the Great Lakes region, and Canada.
Dr Jorge Parada, a medical advisor at the National Pest Management Association in Chicago, told Fox: ‘Powassan can be transmitted in as little as 15 minutes after the infected tick bites, while Lyme disease usually requires a 36- to 48-hour attachment time for transmission.’
While transmission is fast, those who contract the Powassan virus may not develop symptoms for up to four weeks after exposure.
In some cases, severe illnesses can lead to complications such as encephalitis and meningitis.
There is no treatment for Powassan virus. The CDC recommends that most patients rest, drink plenty of fluids, and take over-the-counter pain medications to relieve some of the symptoms.
People with severe cases of the disease may need to be taken to hospital for support for breathing, staying hydrated, or reducing swelling in the brain.
Cases of another potentially life-threatening allergy to meat triggered by tick bites are also on the rise, experts have warned.
Alpha-gal syndrome was first linked to tick saliva 15 years ago, which can cause sufferers to develop the allergy even if they’ve never suffered symptoms before.
The disease is an immune response to a sugar called alpha-gal, found in the meat of most mammals. The allergy doesn’t impact the consumption of seafood or poultry. Chicken, turkey and eggs are also okay to eat.
While the allergy can take weeks or months to develop, symptoms can occur within hours of consuming meat or cheese.
Most commonly associated with lone star ticks – which are native to the Americas but not the UK – scientists now believe other types of tick can also spread the allergy.
These include the black-legged tick, known as the sheep tick or castor bean tick in the UK, which is a primary spreader of Lyme disease.
Some 450,000 Americans are thought to have developed Alpha-gal syndrome, according to a study by the Centers for Disease Control and Prevention.
In the UK, the allergic response remains very rare.
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