First case of ‘brain swelling’ bug in US state proves fatal – as alert issued

A DEADLY ‘brain swelling’ disease which is spread to humans by tick bites has been found in US state for the first time.

An unnamed person died of Powassan virus in Maryland, US, the authorities confirmed.

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Dr Nilesh Kalyanaraman, of Maryland Department of Health, said: “We are very saddened to report the first death due to the Powassan virus in our state.”

The rare bug kills up to one in ten of those infected by causing swelling of the brain (known as encephalitis) or the membranes surrounding the brain and spinal cord (meningitis).

It marks the first-ever case of Powassan found in Maryland and was recorded on September 22.

It’s believed the victim contracted the virus in Canada and returned to Maryland afterwards. 

In an update, posted on the Department of Health’s website, Dr Nilesh added: “We do not believe that Powassan poses any threat of local transmission in Maryland.

“As always, we urge everyone to practice good habits when in areas that could have ticks or avoid those areas altogether.”

There are no vaccines to prevent or medicines to treat Powassan virus disease, which is why taking preventative measures when outdoors is so important.

To avoid tick bites, the Centers for Disease Control and Prevention recommends steering clear of wooded and brushy areas with high grass and leaf litter and applying insect repellent before activities like camping or gardening.

Wearing long sleeves and long pants tucked into socks can also help, as can spraying clothing and camping gear with products containing the insecticide permethrin.

Most cases in the US occur in the northeast and Great Lakes regions from late spring through mid-fall when ticks are most active. 

The majority of cases recorded in the last decade have been in Massachusetts, Minnesota, Wisconsin and New York.

US Powassan cases have risen over the last decade as deer ticks became more widespread.

The CDC identified 20 Powassan cases in 2020, the last year for which data was available, and 39 cases in 2019. In 2011, for comparison, just 12 cases were recorded.

Although Powassan virus has not been found in the UK, some ticks in the UK carry the bacteria that causes Lyme disease and tick-borne encephalitis virus.

What are the symptoms of Powassan virus?

Most people infected with Powassan virus do not have symptoms.

For people with symptoms, the time from tick bite to feeling sick ranges from one week to one month.

Initial symptoms can include fever, headache, vomiting, and weakness.

Symptoms of severe disease include confusion, loss of coordination, difficulty speaking, and seizures.

Approximately half of the people who survive severe disease have long-term health problems such as recurring headaches, loss of muscle mass and strength, and memory problems.