Patrick Scanlon

The remarkable story of Chinese scientist Tu Youyou, who won the 2015 Nobel Prize in Physiology or Medicine for her discovery of artemisinin — a breakthrough drug that has saved millions of lives from malaria worldwide. In the late 1960s and early 1970s, amid China's "Project 523" (a secret effort to combat malaria during the Vietnam War era), Tu Youyou and her team reviewed thousands of ancient Chinese medical texts for herbal remedies against "intermittent fevers" (a classic description of malaria symptoms). Most preparations involved boiling herbs into decoctions, but one key reference from the Eastern Jin Dynasty (around 340 AD) stood out — Ge Hong's A Handbook of Prescriptions for Emergencies (肘后备急方). It described using qinghao (sweet wormwood, Artemisia annua) by taking "a handful of qinghao, immerse in two liters of water, wring out the juice, and drink it all." Notably, this method used cold water steeping and wringing (squeezing) rather than heat. This detail was pivotal: Traditional boiling methods had yielded inconsistent or ineffective results in modern tests because high temperatures degraded the active compound. Tu hypothesized that heat was destroying the antimalarial potency, so her team shifted to low-temperature extraction techniques. In September 1971, they experimented with solvents like ethyl ether (which has a low boiling point of about 35°C) to extract the leaves and stems at reduced temperatures. On October 4, 1971, they obtained a highly effective sample (#191) that achieved 100% inhibition of malaria parasites in rodent and monkey models. This led to the isolation of artemisinin (also called qinghaosu) in 1972. Tu even tested the safety of early extracts on herself first. Artemisinin-based combination therapies (ACTs) are now the WHO-recommended first-line treatment for malaria, dramatically reducing deaths, especially in Africa and Asia.