This Hominin Species Is the Reason Why Herpes Exists in Humans Today

The Paranthropus boisei, a species of an ancient bipedal hominid that roamed around the Earth 2.4 until 1.4 million years ago, could be responsible for passing off the first case of genital herpes to humans.

Between 3 and 1.4 million years ago, genital herpes from African apes infected our human ancestors, which researchers believe likely occurred through an intermediate homin species unrelated to humans. According to a new study, which was published in Virus Evolution, found evidence suggesting that a Homo ancestor, Homo habilis, may have contracted genital herpes from ancient chimpanzees by eating their meat. The Homo habilis then sexually passed the virus to Paranthropus boisei, which passed it to the Homo erectus.

“Our model identifies Paranthropus boisei as the most likely intermediate host of HSV2, while Homo habilis may also have played a role in the initial transmission of HSV2 from the ancestors of chimpanzees to P.boisei,” the researchers wrote in their study.

The researchers analyzed and showed how the virus was transmitted from chimpanzees to the hominids that once roamed Africa. By researching the changes in topography, climate data, fossil locations and geography, the researchers found Paranthropus boisei as the likely cause for indirectly giving humans genital herpes that now affects one in six American adults.

Researchers point out climate data and fossil locations allowed them to define the species that most likely came into contact with the early chimpanzees and other early humans near water sources.

Scientists explain they found close contact between homo erectus and P. boisei would have been common around water during the time, which provided the opportunity for genital herpes to spread to humans.

“For these viruses to jump species barriers they need a lucky genetic mutation combined with significant fluid exchange. In the case of early hominins, this means through consumption or intercourse — or possibly both,” said study author Charlotte Houldcroft, from Cambridge’s Department of Archaeology.

Genital herpes is considered a major issue. As of 2012, over 400 million people live with the infection. Infection with genital herpes does not often come with symptoms. However, when symptoms do occur, infection leaves behind sources known as ulcers, as well as fevers and swollen lymph nodes.