Africans suffering from malaria¹ may be getting sub-standard treatment, a study by US-based experts has suggested.

一组美国科学家经过研究得出结论，遭受疟疾之苦的非洲人可能接受着非正规的治疗。

The experts say their research threw up a disturbing trend

Researchers from the Pharmacopeia（药典，处方汇编） group found that between 26% and 44% of anti-malaria drugs in Uganda, Senegal（塞内加尔） and Madagascar（马达加斯加） were of poor quality.

The group, conducting the study for the World Health Organization, said low-grade drugs were being used in both public and private health practices.

Some 90% of malaria deaths in the world occur in Africa.

The experts subjected 200 samples of anti-malaria drugs to quality-control testing in a US laboratory.

They found 44% of the drugs from Senegal failed the testing, followed by 30% from Madagascar and 26% from Uganda.

Patrick Lukulay, director of the US government-funded Pharmacopeia programme, said it was a "disturbing（烦扰的，令人不安的） trend".

"It is worrisome that almost all of the poor-quality data that was obtained was a result of inadequate² amounts of active [ingredients材料，作料] or the presence of impurities³（杂质） in the product," he said.

The particular problem they identified was with artemisinin（青蒿素） -based drugs.

The chemical is one of the few affordable⁴ and effective treatments for malaria.

But the WHO's malaria programme chief Robert Newman said low-quality versions of the drug could increase resistance because they would not kill all of the parasites⁵.

"There are a number of things that need to be done - as a global community we need to support countries in strengthening their regulatory controls," Mr Newman said.

The researchers also studied drugs from seven other countries - Cameroon（喀麦隆） , Ethiopia, Ghana（加纳） , Kenya, Malawi, Nigeria and Tanzania（坦桑尼亚） - but have not yet released data from those nations.

However, Mr Lukulay said Ghana had already withdrawn⁶ more than 20 drugs from the market after seeing initial results.