Clinical trials have begun in mainland China for a possible vaccine for the coronavirus . At present, most credible reports suggest an effective vaccine won’t be available for many months and possibly not until 2021. Certain countries see the development of a vaccine as a race with national prestige at stake, reminiscent of the Cold War rivalry between the United States and Soviet Union in everything from culture to sports, and from space exploration to nuclear warheads. While competition may encourage progress, imagine how much more could be achieved – and how much quicker – if data and findings were shared across national borders. It is sobering that, even in a global emergency, the notion of our shared humanity fails to trump narrow tribalism. The first successful vaccine in modern history was the smallpox vaccine, developed by Edward Jenner in late 18th century Britain. Highly infectious and often fatal, smallpox was the scourge of the ancient world. Taoist medical practitioner Ge Hong (AD283-343) was the first Chinese writer to mention the disease, tracing its appearance in China to AD23-26. The ancient Chinese used a method called variolation to immunise against smallpox. According to legend, a physician on Mount Emei, in Sichuan, originated the method around the 11th century and was invited to the capital, where he successfully immunised the son of the Grand Councillor. This story is probably apocryphal but we do know that, by the middle of the Ming dynasty (1368-1644), prevention of smallpox by variolation was being widely practised in China. What is herd immunity? And can it stop the coronavirus? There were several ways a person could be immunised using this technique. The pus of the pox from an afflicted person would be collected in cotton wool and stuffed up the nose of the person being inoculated. Marginally less revolting was to grind dried pox scabs to powder and blow it up the nose through a long pipe. The least repulsive method wasto wear the clothes of the smallpox “donor”. Whichever method was used, soon afterwards, the “receiver” would develop a mild case of smallpox, and two to four weeks later, would recover and gain immunity. While variolation was quite successful, sometimes deaths occurred, especially if the donors had serious cases. Occasionally, the immunity lapsed and the variolated person caught smallpox later in life. Variolation was also practised in Africa and the Middle East. It was in Constantinople, in modern Turkey, that it caught the attention of Europeans, in the early 1700s, and became the precursor to modern vaccination. Jenner discovered the much less serious disease cowpox could induce immunity against smallpox. The scientific name of cowpox, variolae vaccinae , gave us the words “vaccine” and “vaccination”. Variolation is now banned in many places, but a variation survives in so-called “pox parties”, in which children are deliberately exposed to chickenpox or measles in the hope they will acquire immunity rather than suffer the more serious diseases as adults. Please don’t try this with the coronavirus.