Experts warn millions of lives are at risk as world's most effective malaria drug loses its potency

Millions of lives are at risk as one of the best drugs used to treat malaria is losing its potency, say experts.
Resistant strains of the deadliest and most common form of the disease have been confirmed on the border of Thailand and Burma.
Tests revealed that the malaria parasite, Plasmodium falciparum has undergone a genetic change making it resistant to artemisinin, one of the world's most popular drug treatments.

Tests revealed that the malaria parasite, Plasmodium falciparum has undergone a genetic change making it resistant to one of the most popular drug treatments

Experts now fear if it cannot be defeated thousands more lives could be lost to the disease, as drug-resistant strains of the virus could potentially spread across India and Africa.

 

Lead researcher, Professor Francois Nosten, director of the Shoklo Malaria Research Unit in Thailand, said: 'This is very worrying indeed and suggests that we are in a race against time to control malaria in these regions before drug resistance worsens and develops and spreads further.
'The effect of that happening could be devastating. Malaria already kills hundreds of thousands of people a year - if our drugs become ineffective, this figure will rise dramatically.'
In 2010, malaria killed an estimated 655,000 people worldwide, mostly young children and pregnant women.
However, some estimates put the annual death toll at more than one million.

In 2010, malaria killed an estimated 655,000 people worldwide, but some estimates put the death toll at over one million

Since 2006 Artemesinin has been regarded as a miracle cure for malaria because it has few side-effects and, up to now, has been almost 100 per cent effective.
Resistance to it was first detected in western Cambodia in 2009, and despite efforts to contain the spread, it appears that it has now spread 800km along Thailand's north-western border with Burma.
Concerns have been raised as, twice before, resistance to the then gold standard anti-malarial drugs – chloroquine and sulfadoxine-pyrimethamine –  started in the same region before spreading to South-east Asia and Africa, leading to the deaths of millions of children.
Prof Nosten added: 'We have now seen the emergence of malaria resistant to our best drugs, and these resistant parasites are not confined to western Cambodia.'
Prof Nosten, along with a team of British and Thai scientists measured the effectiveness of artemisinin treatments in more than 3,000 malaria patients who attended clinics in the region.

Preventing the spread of artemisinin resistance to other regions is imperative, but as we can see here, it is going to be increasingly difficult

Over a 10-year period between 2001 and 2010, the average time taken to reduce the number of parasites in the blood by half rose from 2.6 hours to 3.7 hours.

This is said to be a clear sign that the drugs are becoming less effective. The proportion of slow-clearing infections increased over the same period from six to 200 out of every 1,000 cases.

The scientists warned in a paper published in The Lancet medical journal that  resistance rates on the Thai-Burmese border could match those in western Cambodia within two to six years.
Two US experts commenting on the findings highlight that artemisinin combination treatments were the last bastion of defence against P. falciparum.

Dr Anne-Catrin Uhlemann and Dr David Fidock, from Columbia University College of Physicians and Surgeons in New York, wrote: 'Antimalarial control efforts are vitally dependent on artemisinin combination treatments. Should these regimens fail, no other drugs are ready for deployment.'

While Dr Jimmy Whitworth, head of international activities at the Wellcome Trust, said: 'Researchers will need to monitor these outbreaks and follow them closely to make sure they are not spreading.

'Preventing the spread of artemisinin resistance to other regions is imperative, but as we can see here, it is going to be increasingly difficult.'
Approximately 1,500 travellers return to the UK with malaria every year. In 2008, there were 1,370 cases of malaria reported and six deaths in the UK.