Each year, about 500 million people in the world contract malaria, and about one million are killed by the disease, many of them children. In recent years, the most effective treatment against the disease was a compound based on a drug called artemisinin. But the World Health Organization (WHO) warned Thursday that if the drug is used alone, the parasite that causes malaria will be able to evolve so that it will eventually prove resistant to the drug.
The World Heath Organization says pharmaceutical companies should stop marketing artemisinin alone as a so-called monotherapy to treat malaria. Continuing to do so, it says, increases the risk that the malaria parasite will one day resist the drug, which has happened with all previous malaria therapies.
That is why the World Health Organization is urging that artemisinin, which is derived from wormwood, an ancient Chinese herb, be used in combination with at least one other drug. The new malaria therapies combine artemisinin with drugs based on quinine. These Artemisinin Combination Therapies (ACTs) are 95-percent effective in curing malaria.
The head of WHO's malaria department, Dr. Arata Kochi, says the importance of artemisinin cannot be overstated.
"If we lose artemisinin, we will no longer have an effective cure for malaria. WHO estimates that it will take at least ten years before another effective medicine may become available," he said.
The WHO says many companies are marketing the drug as a single therapy, particularly in Africa, taking advantage of weak regulatory regimes there. Dr. Kochi says he and his colleagues met Wednesday with representatives of about 10 of them and asked them to stop marketing artemisinin monotherapies.
While the WHO has no regulatory powers, there are steps it could take. Dr. Kochi says it could encourage funding agencies like the World Bank and Global Fund not to buy ACTs from companies that continue to market monotherapies. The WHO also hopes to persuade the governments that have influence over drug exports not to sell the raw materials from which the drugs are derived to those companies that continue to market monotherapies.
And the WHO warns that the people of Asia, Africa and Latin America, the regions where malaria most often strikes, are not the only ones in jeopardy if artemisinin becomes ineffective. It says millions of tourists and business travelers who go to these regions will also be endangered.