The Story Behind the Discovery

Tu Youyou was 30 years old in 1967 when the Chinese government quietly assigned her to one of the most secretive medical missions of the Cold War. The Vietnam War was raging, and malaria was killing more soldiers on both sides than enemy bullets. Chairman Mao had asked military scientists to find a cure. The project was classified. Tu was given a small laboratory, access to thousands of ancient Chinese medical manuscripts, and a team of researchers. She was looking for a clue that might have been written down by a healer 1,500 years ago. Forty-eight years later, in October 2015, she walked onto the stage in Stockholm to accept the Nobel Prize in Physiology or Medicine — the first Chinese woman in history to win a Nobel Prize in science.

What the Science Actually Shows

To understand why this discovery matters so profoundly, you need to understand what malaria is and what it does. It is a parasitic infection carried by female Anopheles mosquitoes. When an infected mosquito bites you, it injects Plasmodium parasites into your bloodstream. These travel to your liver, multiply rapidly, then burst into your red blood cells and destroy them in relentless cycles of fever, chills, and organ failure. Malaria shaped human history — it likely killed Alexander the Great, devastated Roman legions, and contributed to the fall of ancient empires. By the 1960s, the malaria parasite had evolved resistance to chloroquine, the standard treatment, and doctors in Vietnam were nearly out of options.

Why This Changes Everything

Tu and her team screened over 2,000 traditional herbal remedies and tested more than 380 plant extracts on infected mice. Most failed. Then, buried in a 4th-century manuscript called ‘A Handbook of Prescriptions for Emergencies’ by the physician Ge Hong, she found a single sentence: ‘A handful of qinghao immersed with two litres of water, wring out the juice and drink it all.’ What struck Tu was the word ‘immerse’ — not ‘boil.’ Standard Chinese herbal preparation involved boiling plants. But Ge Hong specifically said not to apply heat. She realised that heat was destroying the active compound. She switched to a cold ether extraction process. The resulting extract was 100 percent effective at clearing malaria parasites from infected mice.

The Bigger Picture

To accelerate human trials in 1970s China, Tu Youyou and two colleagues volunteered to dose themselves first, demonstrating the drug was safe. The formal clinical trial in 1972 treated 21 critically ill patients in Hainan Province — all of them recovered dramatically. The drug works by reacting with iron inside the malaria parasite’s cells, generating free radicals that destroy the parasite while leaving healthy human cells largely unharmed. Despite saving millions of lives, Tu’s work was essentially invisible to Western science for decades — classified, published only in Chinese, and uncredited due to collective authorship norms.

What Comes Next

The 2011 Lasker Award was Tu’s first major international recognition. The Nobel followed in 2015. When Swedish reporters asked how she felt about having no PhD, no overseas degree, and no Chinese Academy membership, Tu replied simply: ‘I just did what a doctor and scientist should do.’ Today, artemisinin-based combination therapies (ACTs) are the WHO’s recommended first-line treatment for malaria in every affected region on Earth, treating hundreds of millions of cases annually. The answer to one of humanity’s oldest killers was hiding in a 1,600-year-old handwritten text — and it took one scientist’s careful reading of an ancient word to find it. For students, this represents exactly the kind of event that defines a generation’s scientific education. Future textbooks will describe this development as a turning point. But it is worth remembering that what looks clean and inevitable in a textbook was, in reality, the product of years of uncertainty, failed experiments, funding struggles, and the kind of stubbornness that characterises the best scientists. Progress in science rarely looks the way it does in retrospect.

Sources: Nobel Prize Committee 2015, WHO Global Malaria Report, Tu Youyou Nobel Lecture. Image: Wikimedia Commons — Public Domain.
Image: Artemisia annua plant — Wikimedia Commons public domain (Rolf Engstrand)