A key malaria treatment has failed for the first time in patients being treated in the UK.
The drug combination artemether-lumefantrine was unsuccessful in curing four patients, who had all visited Africa.
However, all patients were then treated using other therapies. The failure is causing concern that the parasite is evolving resistance. A team at the London School of Hygiene & Tropical Medicine said it was too early to panic.
But it warned things could suddenly get worse and demanded an urgent appraisal of drug-resistance levels in Africa.
Malaria parasites are spread by bites from infected mosquitoes. It is a major killer of the under-fives with one child dying from the disease every two minutes.
Up to 2,000 people are treated for malaria in the UK each year, always after foreign travel. Most are treated with artemether-lumefantrine.
Of the four cases of failure, two were associated with travel to Uganda, one with Angola and one with Liberia.
This suggests drug-resistant malaria could be emerging over wide regions of the continent.
