Travelers not taking antimalarial drugs and returning to Britain with a potentially fatal form of malaria have increased in number, health officials said yesterday.
A Health Protection Agency (HPA) study identified 6,753 cases of falciparum malaria diagnosed in the UK between 2002 and 2006.
This is a 30% increase in the last 15 years, reports the British Medical Journal.
According to experts, many of the malarial cases in the UK occur among migrants who become infected while visiting west Africa where the disease is endemic. Many travellers do not take antimalarial pills because they believe they are already immune.
Professor Peter Chiodini, head of the HPA's Malaria Reference Laboratory, said: "There is a prevailing myth that travelers who were born in a malaria-endemic country such as Africa have some 'natural' immunity to malaria and this is simply not the case."
"Like all other people who go to Africa and Asia they need to make sure they take their anti-malaria drugs and follow the guidelines that are there to protect everyone," he added.
Cases of malaria were found to be concentrated in communities where people frequently travelled to west Africa. Some 96% of falciparum malaria infections followed visits to west Africa, with more than half the cases in travellers returning from Nigeria and Ghana.
It has been observed that travel to areas where malaria is endemic has increased sharply in the past 20 years, from less than 600,000 visits in 1987, to 2.6 million in 2004.
According to the report only two-fifths of the UK travelers had made any effort to prevent malaria by taking prophylaxis drugs before or during their trip, especially those born in or with family ties to malaria-endemic areas.
"Half of all people who go travelling don't seek any medical advice before going, particularly to tropical destinations where the risk of infectious diseases is significant," said Jane Zuckerman, who runs a travel clinic at the Royal Free and University Medical School in London.
Travel medicine advice is freely available at GP surgeries, and specialist travel medicine clinics in the UK's bigger cities.