Ancient primate may be responsible for genital herpes

Our ancient ancestors have been catching herpes since before we were human. The infection is quite common today; the World Health Organization estimates that two-thirds of adults under 50 are infected with the herpes virus that causes oral cold sores. One in six have genital herpes. Humans might have dodged herpes' below-the-belt blow if it weren't for an ancient encounter between early members of our genus and a more distant primate relative. Blame genital herpes on Paranthropus boisei, a heavy-jawed primate with teeth so large it earned the nickname the 'Nutcracker Man'.

Herpes viruses are as varied as they are old. There are more than 100 different kinds of herpes. Eight regularly infect humans, causing diseases like chickenpox and mononucleosis. Scientists had previously analyzed the herpes genome and created a viral family tree. Oral herpes, HSV-1, has been around since humans and chimpanzees split 6 million years ago. The researchers also discovered that HSV-2 must have jumped from ancestral chimpanzees into the human lineage later, as recently as 1.4 million years ago. In a model's most likely scenario, Paranthropus boisei infected a human ancestor called Homo erectus.

Homo erectus