In a cramped Beijing laboratory in 1971, Dr Tu Youyou stared at a petri dish under a microscope. For the 191st time, an extract from a plant had failed to kill the malaria parasites swimming in the dish. Her team was exhausted, the Cultural Revolution raged outside, and funding was nearly gone. But Tu Youyou, a 41-year-old pharmacologist, refused to give up. She reached for a stack of ancient Chinese medical texts, their pages yellowed and brittle. One recipe, written by Ge Hong in 340 AD, described soaking sweet wormwood in cold water and drinking the juice to treat fevers.

That small, specific detail—cold water, not hot—would change everything. Tu Youyou was born in 1930 in Ningbo, a coastal city in eastern China. As a child, she suffered from tuberculosis, a disease that kept her bedridden for years. That experience sparked her interest in medicine. She studied pharmacy at Peking University, graduating in 1955, and later trained in traditional Chinese medicine. In 1969, during the Vietnam War, North Vietnam's leader Ho Chi Minh asked China for help developing a malaria treatment. The disease was killing more soldiers than bullets.

China's government launched a secret military project called Project 523, and Tu Youyou was appointed to lead the herbal medicine research team. The challenge was immense. Tu's team tested over 2,000 herbal recipes and extracted compounds from 380 plants, but nothing worked reliably. The turning point came when Tu revisited Ge Hong's fourth-century text. Most researchers boiled the wormwood, but Ge Hong's recipe specified using only the juice squeezed from fresh leaves. Tu realised that high heat might destroy the active compound. She redesigned the extraction process, using ether at low temperature to isolate the plant's essence.

In 1969, during the Vietnam War, North Vietnam's leader Ho Chi Minh asked China for help developing a malaria treatment.

In October 1971, her team finally produced a pure, stable extract that killed 100% of malaria parasites in mice. But the real test was yet to come. The extract had to be tested on humans, and the team had no time for animal safety trials. Tu Youyou volunteered to be the first human subject. She and two colleagues each took a dose of the extract. For days, they monitored their own blood and organs for signs of toxicity. When no ill effects appeared, they moved to clinical trials on malaria patients.

The results were dramatic: patients with severe malaria recovered within days. Tu Youyou had discovered artemisinin, the most effective antimalarial drug ever developed. The Cultural Revolution made Tu's work even harder. Her husband was sent to a labour camp, and she had to leave her two young daughters with relatives. She worked 16-hour days in a poorly equipped lab, often sleeping on a cot. When the project was finally declassified in the late 1970s, Tu Youyou received little recognition. Her research was published anonymously, and for decades, her contribution was overlooked.

Yet she never complained. She simply continued her research, refining the drug and saving millions of lives. In 2015, Tu Youyou was awarded the Nobel Prize in Physiology or Medicine, the first Chinese woman to win a Nobel science prize. In her acceptance speech, she quoted Ge Hong's ancient text and thanked the wisdom of traditional Chinese medicine. She donated most of her prize money to research. Today, artemisinin-based combination therapies are the standard treatment for malaria worldwide, reducing death rates by over 60% in Africa alone. Tu Youyou's discovery has saved tens of millions of lives.

One memorable detail: Tu Youyou's breakthrough came from a recipe written 1,600 years before she was born. She often said that the ancient healer Ge Hong was her true collaborator. Her story shows that progress doesn't always come from new technology—sometimes it comes from listening to the past with fresh eyes. Tu Youyou proved that a quiet researcher, armed with patience and a yellowed book, could change the world.