UK faces summers of malaria
Large parts of southern England and Wales are at risk from malaria, scientists have calculated.
They say that the disease is most likely to take hold in river estuaries and low-lying wetlands.
Researchers at Durham University, commissioned by the Department of Health, used a mathematical model to predict how global warming will increase the threat of malaria in coming years.
They focused on vivax malaria which can be transmitted by a species of mosquito commonly found in Britain, Anopheles atroparvus.
Humans become infected when bitten by a mosquito that is carrying the parasite.
A rise in temperature encourages the mosquito to breed and feed more rapidly. It also speeds up the maturation of the malaria parasite.
Malaria was once common in many parts of the UK, and was a leading cause of death in many marsh communities between the 16th and 19th centuries.
The areas that were most badly affected included the Fens, Thames estuary south-east Kent, the Somerset levels, the Severn estuary, the Holderness of Yorkshire and the coastal districts of the Firth of Forth.
The researchers have calculated that if global warming continues at its current rate, some of these same areas could once again become breeding centres for malaria for up to four months each year by the end of this century.
Researcher Dr Steve Lindsay said: "Present day summer temperatures are warm enough to support the transmission of malarial parasites by indigenous mosquitoes in the warmest parts of the country for two months each year.
"By 2050 large parts of Southern England could get malarial transmissions and the season could be increased to four months by the end of the century.
"Health authorities should be aware of the possibility malaria could occur.
"There is no way it could become entrenched but an outbreak is possible."
At present, mosquitoes in the UK are not infected with the malaria parasite.
However, increased foreign travel has led to a sharp increase in the number of people bringing the disease back to the UK.
Chief Medical Officer for England Professor Sir Liam Donaldson warned earlier this month that the tropical diseases posed a growing threat to the UK.
Dr Peter Chiodini, of the Hospital for Tropical Diseases in London, said malaria was a particular problem, particularly because the early symptoms can be confused with flu.
The research is published in the journal Global Change and Human Health.