Source:
https://scmp.com/news/china/society/article/1864597/drug-chinas-nobel-prize-winner-tu-youyou-worked-has-saved
China

Chinese Nobel Prize winner Tu Youyou’s drug has saved lives of millions of malaria sufferers

Chinese scientist Tu Youyou carried out her research at the height of the mainland’s Cultural Revolution.

A frontline drug in the fight against malaria, artemisinin has a history going back many centuries, for it traces its past to ancient Chinese medicine.

The mainland scientist Tu Youyou, who helped discover its therapeutic treasures in laboratory work at the height of the mainland’s Cultural Revolution, was honoured on Monday when she jointly won the 2015 Nobel Prize for medicine.

Here are some facts about the drug.


What is it?

Artemisinin kills Plasmodium parasites that cause malaria. It is derived from a plant called sweet wormwood – Artemisia annua in Latin, or qinghao in Chinese.

I’m reasonably confident that we can get another five to seven – maybe 10 years’ life out of our artemisinin combination approach Parasitology expert Colin Sutherland

It is in use today because of work in 1970s by Tu and her team, who spotted references to a fever-easing plant in ancient Chinese medical texts and sought to extract the active ingredient to combat malaria.

From the 1990s, artemisinin gradually took on a frontline role, replacing previous generations of medicines that had lost their effectiveness as malaria parasites became resistant to them.

The drug acted fast initially to attack the parasite, but was used in conjunction with longer-lasting medicines to destroy those parasites that continued to hold out, said Teresa Tiffert, a malaria researcher at Britain’s Cambridge University.


How did it change malaria treatment?

Artemisinin has greatly increased the odds of survival for people hit with the most stubborn strains of the disease.

The chances of dying from malaria have halved from one in five a decade ago to nearly one in 10 today in severe cases where people were hospitalised.

While vital, it is but one element in a broader strategy to fight malaria, which includes simple, low-cost measures such as distributing insecticide-treated bednets.

The coordinated effort had reduced the number of deaths by nearly three-quarters over the past decade, said parasitology expert Colin Sutherland at the London School of Hygiene and Tropical Medicine.

Statistics provided by the the World Health Organisation show that malaria deaths have fallen from about two million per year in the early 2000s to an estimated 584,000 in 2013.

Health authorities estimate there are nearly 200 million new cases of the disease every year, with about 90 per cent of deaths in Africa.


What does the future hold for artemisinin?

The malaria parasite has a tremendous ability to mutate, causing it to build resistance to treatments when they are prescribed or used incorrectly.

There have been two examples in history of malaria drugs losing their effect, at a cost of millions of lives.

From the 1950s to 1970s, chloroquine-resistant parasites spread from Asia to Africa.

Chloroquine was then replaced by sulphadoxine-pyrimethamine (SP), which itself lost its parasite-killing powers and was followed by artemisinin.

In February this year, researchers said they had observed malaria strains showing resistance to artemisinin in Myanmar, and raised fears it could spread westward to Bangladesh and India, even beyond.

In Africa, where malaria claims most of its victims, some artemisinin-based therapies are also no longer working as well as they used to, doctorshave reported.

At a WHO meeting this year, experts will consider recommendations to beef up the combination therapy, perhaps by increasing doses of the drug or the duration of treatment.

“I’m reasonably confident that we can get another five to seven – maybe 10 years’ life out of our artemisinin combination approach, by which time we should have a new generation of combination therapies ready to go,” Sutherland said.