Cold water. Everyone had been boiling it. That one word led to artemisinin, the core of the medicines that now treat malaria worldwide, and in 2015 to a Nobel Prize: the first ever won by a woman who was a citizen of the People's Republic of China, and the first Chinese Nobel in Physiology or Medicine.
About this series: History-Makers profiles people whose specific, documented contributions changed human life at enormous scale. Tu Youyou is here because the drug she found is the backbone of malaria treatment for hundreds of millions of people, and because her story shows how much of science is collective, with credit that is hard to divide.
A note: this is history, not medical advice. Malaria is a medical emergency; anyone with fever after time in a malaria area should see a doctor immediately.
The emergency behind the discovery
Malaria is caused by parasites carried by mosquitoes. It is still one of humanity's great killers: in 2024 the World Health Organization estimated about 282 million cases and 610,000 deaths, about 95 percent of them in Africa, where roughly three in four deaths are children under five.
In the 1960s the parasite was beating the existing drugs. Resistance to chloroquine was spreading, and soldiers fighting in the jungles of Vietnam were falling sick in large numbers. On 23 May 1967 China launched a secret military research programme, known by its start date as Project 523, to find new antimalarials. It eventually drew in more than 500 scientists across many institutes, working in three streams: synthetic chemistry, clinical studies and traditional Chinese medicine.
The search
Tu, born in Ningbo in 1930 and trained in pharmacology, was put in charge of her institute's group in 1969. She and her colleagues combed through ancient texts and folk remedies, collecting more than 2,000 recipes, and made 380 extracts from about 200 herbs to test on mice.
Qinghao, sweet wormwood (Artemisia annua), had a long history in Chinese medicine for fevers, but its extracts behaved inconsistently. Reading Ge Hong's instruction to steep it in cold water, Tu reasoned that heat might be destroying the active ingredient. She switched to extracting it with ether at low temperature. In 1971 the new extract proved effective against malaria parasites in mice and monkeys.
The breakthrough wasn't a new herb. It was noticing that an old recipe said "cold," and taking that seriously.
The test, and the molecule
Before human trials, the team needed to know the extract was safe. Tu volunteered to be the first person to take it. She had no ill effects, and trials in patients followed. In 1972 her group isolated the pure active compound, qinghaosu, now called artemisinin. Other teams in Project 523 helped work out its unusual chemical structure, determined in 1975, and developed more effective derivatives, such as artesunate and artemether.
Because of the secrecy of the programme and the politics of the Cultural Revolution, the work was first published anonymously, in 1977. The outside world learned slowly what Chinese scientists had found.
From a secret project to the world's malaria medicine
Artemisinin kills malaria parasites remarkably fast. To protect it from resistance, the World Health Organization in 2006 called for an end to artemisinin used alone; instead it's given in artemisinin-based combination therapies (ACTs), paired with a slower, longer-lasting partner drug. ACTs are now the standard first-line treatment for the most dangerous form of malaria across the world. One of the most widely used, artemether-lumefantrine, came from another Project 523 team led by Zhou Yiqing.
Tu received the Lasker Award in 2011 and, in 2015, half of the Nobel Prize in Physiology or Medicine "for her discoveries concerning a novel therapy against Malaria." In China she became known as the "three-without" laureate: no doctorate, no research training abroad, and no membership of the national academies.
The honest complications
Credit is genuinely shared. Project 523 involved hundreds of researchers. Groups in Yunnan and Shandong independently obtained crystalline artemisinin in 1973; chemists in Shanghai determined its structure; Li Guoqiao led clinical work and helped develop artesunate; Luo Zeyuan and others made key contributions. When Tu received the Lasker Award, Science reported that it "rekindled debate" in China over who deserved recognition. The case for singling her out is that her team's low-temperature extraction produced the first effective extract, the step everything else built on; the case against is that a drug is never one step.
Traditional medicine is part of the story, but not a blanket endorsement. Ge Hong's text pointed the way, but it took modern chemistry, animal testing and clinical trials to turn a folk remedy into a reliable drug. Thousands of other traditional recipes screened in the same project did not work.
The parasite is fighting back. Partial resistance to artemisinin was first confirmed in western Cambodia in 2008 and spread through Southeast Asia. The WHO has now confirmed partial resistance in Eritrea, Rwanda, Uganda and Tanzania, and suspects it in several other African countries. Protecting ACTs is one of the most urgent tasks in global health.
Malaria hasn't been beaten. Bed nets, insecticides, and now two malaria vaccines are as important as drugs, and deaths have risen again in recent years after earlier progress.
Honorable mentions
- Ge Hong (4th century), whose practical handbook preserved the clue.
- Zhou Yiqing and his team, who created artemether-lumefantrine, one of the most widely used ACTs.
- Li Guoqiao, who ran key clinical trials and helped develop artesunate.
- Alphonse Laveran and Ronald Ross, who in the 1880s and 1890s showed that malaria is caused by a parasite and spread by mosquitoes, and both received Nobel Prizes for it.
The takeaway
Tu Youyou led the Project 523 team that, guided by a fourth-century instruction to steep sweet wormwood in cold water, developed a low-temperature extraction that produced the first effective extract in 1971 and pure artemisinin in 1972. Artemisinin-based combination therapies are now the world's frontline treatment for the deadliest malaria, and she shared the 2015 Nobel Prize. The discovery was the work of hundreds of scientists, credit remains debated, and growing resistance in Africa means the story is still being written.
Try this: next time you dismiss an "old" idea, remember Tu Youyou rereading a 1,600-year-old text and finding a detail everyone else had skipped. Take one problem you're stuck on and go back to its oldest written source. Read it slowly, looking for a single word you've been ignoring.
Sources & Further Reading
Sources
- Tu Youyou's biography (born 1930, Ningbo), Project 523 (launched 23 May 1967; more than 500 scientists), her 1969 appointment, the screening of over 2,000 recipes and 380 extracts, the Ge Hong text, low-temperature ether extraction, self-testing, isolation of artemisinin in 1972, and anonymous publication in 1977.
- Nobel Prize in Physiology or Medicine 2015 (half to Tu, half shared by William C. Campbell and Satoshi Εmura); Lasker-DeBakey Clinical Medical Research Award 2011.
- Project 523 contributors: independent isolation in Yunnan and Shandong (1973), structure in Shanghai (1975), Li Guoqiao and artesunate, Zhou Yiqing and artemether-lumefantrine; Science (2011), "Lasker Award Rekindles Debate Over Artemisinin's Discovery."
- WHO malaria fact sheet (2024 estimates: 282 million cases, 610,000 deaths; African Region about 95%; confirmed and suspected partial artemisinin resistance in Africa); WHO's 2006 call to end artemisinin monotherapy; first confirmed resistance in Cambodia, 2008.
Go deeper
- π§ Tu Youyou's 2015 Nobel lecture, in her own words (search the Nobel Prize website, nobelprize.org)
- π WHO β Malaria fact sheet
- π The Fever β Sonia Shah (how malaria has shaped human history, and why it's so hard to defeat)
- π Companion pieces in this series: Louis Pasteur & the Invisible War and Edward Jenner and the End of Smallpox