Malaria has killed more people throughout history than almost any other infectious disease, and for most of the twentieth century, the tools to fight it were running out. By the 1960s, the parasite behind the disease had grown resistant to chloroquine, the drug doctors had relied on for decades. It took a quiet Chinese scientist working under wartime secrecy, armed with a 1,700-year-old medical text rather than a modern laboratory breakthrough, to hand the world its next weapon. Her name is Tu Youyou, and her story is as much about the value of old knowledge as it is about modern chemistry.
A Secret Wartime Assignment
Tu Youyou’s involvement in malaria research did not begin as a personal project. It began as a military order. In the mid-1960s, North Vietnam was losing soldiers to drug-resistant malaria faster than to combat, and its leader, Ho Chi Minh, appealed to China for help. Mao Zedong responded by launching Project 523, a classified national program that eventually drew in more than 500 researchers from across China. Tu, a pharmaceutical chemist in her late thirties, was appointed to head one of the research groups in 1969, despite never having earned a doctorate or trained abroad. She took on the assignment in the middle of the Cultural Revolution, a period when scientific work was often disrupted by political upheaval, and reportedly had to leave her young daughters with relatives for extended stretches while she worked.
Searching the Old Texts
Rather than starting from scratch in a lab, Tu’s team combed through classical Chinese medical literature and folk remedies, eventually reviewing more than 2,000 recipes and narrowing them down to roughly 640 candidates worth testing. Around 380 extracts, drawn from some 200 different herbs, were screened against malaria parasites in mice, and progress stalled for a long time.
The breakthrough came from an unexpected source: a short passage in a fourth-century text called “A Handbook of Prescriptions for Emergencies,” written by the physician Ge Hong. It mentioned soaking sweet wormwood, known in Chinese as qinghao, in water to relieve fevers rather than boiling it. That detail nagged at Tu. Earlier tests using heat to extract the plant’s compounds had produced disappointing, inconsistent results. Suspecting that high temperatures were destroying the plant’s active ingredient, she redesigned the extraction process using a low-temperature ether solvent instead. The new method worked. By 1972, her team had isolated a pure, highly potent compound, which they named qinghaosu, later known internationally as artemisinin.
Testing It on Herself First
Before running human trials, Tu and two colleagues volunteered to take the compound themselves to confirm it was safe, a decision she made after early animal toxicity data looked ambiguous. Once satisfied, the team travelled to Hainan province to trial the drug on patients infected with both of the major malaria parasite species, and the results were dramatic: the drug cleared parasites from patients’ bloodstreams faster than any existing treatment. Because Project 523 was a state secret, none of this could be published openly at the time. The first English-language paper on the discovery did not appear until 1979, without individual authors named, and a further account followed in The Lancet in 1982, again without crediting Tu by name.
Decades of Obscurity, Then Recognition
Artemisinin quietly became the backbone of modern malaria treatment. Today, artemisinin-based combination therapies are the World Health Organization’s recommended first-line treatment for the disease, credited with helping cut global malaria deaths substantially since the early 2000s, particularly among children in sub-Saharan Africa. Yet for decades, Tu herself remained almost unknown outside a small circle of Chinese researchers.
That changed in 2011, when NIH malaria researchers Louis Miller and Xinzhuan Su published an investigation in the journal Cell arguing that Tu deserved the primary credit for the discovery. Their conclusion helped Tu win the Lasker-DeBakey Clinical Medical Research Award that year, often seen as a precursor to the Nobel Prize. The claim was not universally accepted; some Chinese scientists, including Peking University neuroscientist Rao Yi, argued that Miller and Su had access to a narrower set of documents than existed and had overstated how clear-cut Tu’s individual role was, given that Project 523 involved hundreds of contributors. The disagreement never fully settled, but it did not stop the momentum: in 2015, Tu received the Nobel Prize in Physiology or Medicine, becoming the first Chinese woman, and one of the few Nobel laureates in medicine anywhere, without a doctorate, a medical degree, or research training abroad.
There is a quiet detail in Tu’s own name that fits her story well. Her father named her Youyou after a line from the ancient “Book of Songs” describing deer calling to each other while grazing on wild wormwood, the very plant she would spend her career studying.
Why Her Story Still Matters
Tu Youyou’s career is often used to argue two very different points at once. To some, it shows that individual persistence and insight can cut through institutional noise and produce a discovery that saves millions of lives. To others, including Tu herself, it is really a story about collective effort: she has repeatedly described artemisinin as a gift drawn from the shared “treasure house” of traditional Chinese medicine, built on the work of hundreds of unnamed colleagues under Project 523. Both readings can be true simultaneously, and the tension between them is itself part of why her case still gets debated in science policy circles today, wherever teams and institutions have to decide how credit for a discovery should be shared.
Malaria has not been defeated. Parasite resistance to artemisinin is now being reported in parts of Southeast Asia, which means the search Tu Youyou once led is, in some ways, starting again. But her method, rooted in patience, careful reading of old sources, and a willingness to test her own convictions, remains a useful template for how the next breakthrough might be found.
References:
- World Health Organisation. Malaria Fact Sheet and Guidance on Artemisinin-based Combination Therapies.
- The Nobel Prize. “Youyou Tu – Facts.” NobelPrize.org, 2015.
- Miller, L. H., & Su, X. “Artemisinin: Discovery from the Chinese Herbal Garden.” Cell, 2011.
- Liao, F. “Discovery of Artemisinin (Qinghaosu).” Molecules, 2009.
- Science/AAAS. “Lasker Award Rekindles Debate Over Artemisinin’s Discovery,” 2011.
- Journal of Clinical Investigation. “From Branch to Bedside: Youyou Tu is Awarded the 2011 Lasker-DeBakey Clinical Medical Research Award,” 2011.
- Lindau Nobel Laureate Meetings. “The Modest Nobel Laureate: Youyou Tu,” 2015.