Smooching Fossils

Listen to Today's Edition:

The spread of the herpes virus began thousands of years ago when kissing became popular among ancient humans, Live Science reported.

The Herpes simplex virus 1 – or HSV-1 – is a very common type of pathogen that mainly causes cold sores around the lips but can sometimes lead to genital herpes. The lifelong condition is mainly passed via oral-to-oral contact and those affected usually catch it during childhood or early adulthood.

There are currently around 3.7 billion people under the age of 50 who are infected, according to the World Health Organization.

To determine how the virus became so ubiquitous, scientists analyzed traces of herpes DNA from the remains of four individuals unearth in Europe.

In their study, researchers looked at the teeth roots of these individuals to dust for genetic “fingerprints” of herpes viruses. They wrote that until now, the oldest herpes genomes collected only dated to 1925. However, the current samples are much older – ranging between 350 and 1,500 years old.

Their findings showed that the HSV-1 virus likely appeared about 5,000 years ago and coincided with the Bronze Age mass migrations from the Eurasian steppes to Europe. But the virus also emerged during a period when kissing was starting to become a common practice.

The team suggests that kissing helped the HSV-1 virus outcompete other strains of herpes but said further study is necessary to establish a proper link.

“Kissing is one of those behaviors that doesn’t fossilize well,” co-author Charlotte Houldcroft told the Guardian.