A Briton who is in a coma after being bitten by a mosquito is thought to have become the first European victim of the deadly “Triple E” virus.

Michael Nicholson, 35, began to feel tired after he returned from a fishing holiday in Rhode Island, in the northeast United States, with bites around his ankles.

When Mr Nicholson, a painter from Livingston, West Lothian, went to see his GP he suffered a seizure and then lost consciousness. If he lives, he is expected to be severely disabled for the rest of his life.

His family are cautioning other holidaymakers to be aware of the rare virus in the US. About a third of all those who contract the virus die.

His sister, Sharan McKenzie, said: “There is no cure for this so the only thing that can be done is prevention. I’m sure that most people are like me in thinking that if you are bitten by a mosquito in the US it’s the same as somewhere like Spain – irritating but not life-threatening.” She added: “He was just an ordinary guy who enjoyed spending time with his family.”

The virus – known as Eastern Equine Encephalitis or Triple E – is regarded as one of the most serious mosquito-borne diseases on the North American continent. It is found mainly in the eastern regions of the US, but transmission to human beings is rare.

Mr Nicholson had travelled to the US in July. He spent six weeks with family and friends in Rhode Island and stayed in a log cabin on the Saco River in northern New Hampshire. He fell ill on August 31, a day after flying home.

Within two days he had lost consciousness and was transferred to the intensive care unit of Western General Hospital, in Edinburgh. The rare condition was diagnosed on September 13. According to Mrs McKenzie, doctors said that it was the first case of Triple E to be discovered in Europe.

Mr Nicholson is being cared for at the hospital’s neurological unit, where he remains unconscious and unresponsive.

“He has opened his eyes, but is not aware of anything,” Mrs McKenzie, 38, said. “Our family has been devastated by this. We have been told that he is likely to be severely disabled at best. It seems that there is nothing we can do apart from warn people. The more people know about this virus, the better.”

US health records show that there were 220 confirmed cases of Triple E between 1964 and 2004, an average of five per year. According to reports there has been one death this year in the US – a six-year-old boy in Alabama.

Mr Nicholson’s local MP, Jim Devine, said that he would be writing to David Miliband, the Foreign Secretary, to urge him to publish an official warning about the dangers of the virus. “This is a very tragic case and I would like people who travel to this part of America to be warned about this,” he said.

Triple E

— Recognised in Massachusetts in 1831 when 75 horses died of encephalitic illness. The first human cases emerged in 1938 when 30 children died in northeastern USA

— The virus is maintained through a bird-mosquito cycle that increases throughout the summer, as more birds and mosquitoes become infected. The first winter frosts end the annual cycle

— Transmission to humans is rare; it generally takes from three to ten days to develop symptoms. Many infected people have no apparent illness; for those who do become ill symptoms range from mild flu-like illness to inflammation of the brain, coma and death. There is no specific treatment

— Since 1964 there have been an average of five cases a year; up to 35 per cent of victims die

— A vaccine is available to protect horses but not human beings. The US Centres for Disease Control recommends that people use repellents to avoid mosquito bites

Source: Times database

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