Medicinal plant from Asia fights malaria, earns cash for small farmers

PATANDI VILLAGE, Tanzania (AP) - Small farmer Atanasia Vincent Moshia stands proudly next to the knee-high plants she's growing to fight two African ills: malaria and poverty. In March, Moshia, who is also an agricultural extension officer with the Tanzanian government, switched from planting the corn and beans she's been growing for years to artemisia annua, from which artemisinin is extracted to make a drug or a combination of drugs used to treat malaria. She expects it to be a more lucrative crop.

Artemisia annua, more commonly known as wormwood or sagewort, has been applied to a variety of ailments, including hemorrhoids, coughs and fevers. China and Vietnam are the main sources of the plant native to Asia, but they have been unable to meet a steep increase in demand. The World Health Organization says demand for artemisinin-based combination drug treatment rose to 30 million courses in 2004, from just two million courses in 2003.

Last year, after trials in several countries, it was found that the plant grows well in East Africa - fitting, as Tanzanian health officials call malaria this country's No. 1 killer. Tanzania has an estimated 16 million to 18 million cases of malaria a year and about 100,000 people, mainly children, die from the disease each year, said Dr. Alex Mwita, program manager of the country's National Malaria Control Program.

Patients' resistance to other anti-malarial drugs has grown over the years, leading the World Health Organization in 2001 to recommend artemisinin-based combination drug treatment to fight the ancient mosquito-borne disease that infects as many as 400 million people and kills one million a year.

"We want people to plant this crop because if we don't, many of us will die of malaria," farmer Moshia said.

She planted her artemisia annua on a part of her tenth-of-a-hectare farm that is near a footpath used by her fellow villagers, so that they can see it and be encouraged to try it.

Farmers need not turn to artemisia annua purely out of idealism. The treelike plant that grows up to two metres does not need as much care as corn, largely acting as its own pesticide and insecticide, Moshia said.

She expects to earn the equivalent of about $45 Cdn in August when she harvests the plant's thick foliage, compared to about $28 she earned a season from her maize crop.

Thomas Dixon, country director for Technoserve, which works with small farmers in Tanzania and Kenya to grow artemisia annua, said that a year ago only a small number grew the plant, but this year the hectares under artemisia annua grew several times. Dixon declined to give specific numbers. Most farming in both countries is done by small farmers.

Dixon said, though, that it is possible a cheaper synthetic version of artemisinin will emerge in a few years.

"We are cautioning farmers not to think of this as a new coffee or a long-term crop, but basically advising them that they probably have a secure market for three or four, maybe five or maybe six years," Dixon said.

Scientists are working on a synthetic version but have not so far perfected it.

For farmers, switching back once the artemisia annua market fades should not be a problem, as the medicinal plant takes less toil on the soil than corn.

In the meantime, increased artemisia annua supplies could bring down the costs of artemisinin-based treatment, crucial in a poor country like Tanzania. Mwita, of Tanzania's anti-malaria program, said artemisinin-based combination treatments cost about $2.50 a dosage. Other anti-malarial drugs cost between 12 and 18 cents a dosage, he said.

Walter Opiyo, co-ordinator of Anamed Kenya, said that a cheaper alternative to artemisinin-based combination drug treatment for malaria is for people growing the plant in their gardens to pluck and dry a few leaves to make an infusion taken over seven days.

There have been no widely recognized scientific studies of such infusions, although Opiyo says his group conducted its own study in Congo and determined it was effective.

Mwita believes that no matter how effective artemisinin-based combination drug treatments are, they are not the only answer to defeat malaria in Africa.

"Several things have to be combined to have the desired effect. You have to produce effective drugs, you have to have ways of controlling this malaria epidemic, you have to prevent transmission of malaria through various ways," like using insecticide-treated mosquito nets, he said.

© The Canadian Press, 2005