Earliest evidence of a human kiss dates back 4,500 years to Mesopotamia

"In ancient Mesopotamia, which is the name for the early human cultures that existed between the Tigris and Euphrates in present-day Iraq and Syria, people wrote in cuneiform script on clay tablets. Many thousands of these clay tablets have survived to this day, and they contain clear examples that kissing was considered a part of romantic intimacy in ancient times, just as kissing could be part of friendships and family members' relations," said Dr Troels Pank Arbøll, an expert on the history of medicine in Mesopotamia, in an official statement.

Aside from this revelation, the team also investigated the effects of kissing on pathogen transmission in prehistoric society.

Unsurprisingly, the authors noted that kissing may have led to the spread of the herpes simplex virus 1-like pathogens in ancient times. This conclusion is based on a large number of ancient medical texts recovered from Mesopotamia.

Some medical texts from the time mention a mysterious disease with symptoms similar to the herpes simplex virus 1. The practice could have also resulted in other orally transmitted diseases, like cold sores.

"It is nevertheless interesting to note some similarities between the disease known as buʾshanu in ancient medical texts from Mesopotamia and the symptoms caused by herpes simplex infections" explained Dr. Sophie Lund, one of the authors of this study.

"The bu'shanu disease was located primarily in or around the mouth and throat, and symptoms included vesicles in or around the mouth, which is one of the dominant signs of herpes infection," she said.

The results have been published in the journal Science. 

Study abstract:

Recent studies maintain that the first known record of human romantic-sexual kissing originates in a Bronze Age manuscript deriving from South Asia (India), tentatively dated to 1500 BCE. Yet, a substantial corpus of overlooked evidence challenges this premise because lip kissing was documented in ancient Mesopotamia and Egypt from at least 2500 BCE onward. Because this behavior did not emerge abruptly or in a specific society but appears to have been practiced in multiple ancient cultures over several millennia, the kiss cannot be regarded as a sudden biological trigger causing a spread of specific pathogens, as recently proposed. Further understanding of the history of kissing in human societies—and its secondary effect on disease transmission—can be gained from a case study of sources from ancient Mesopotamia (modern-day Iraq and Syria).