AIDS has been around for 100 years, longer than anyone realised until now. Old medical specimens from Africa reveal that HIV crossed from chimps to humans around 1908. It then kept circulating in people because central Africa’s first-ever cities were created at the same time.
Until now, the only known sample of HIV from before 1976 (the first known case in today’s global pandemic) came from a patient in 1959, in what is now Kinshasa, in the Democratic Republic of the Congo. Because viruses accumulate mutations over time, the genetic differences between the 1959 sample and more recent ones were…
