An international team of researchers suggests that the modern strain of the herpes simplex virus that causes cold sores has been traced back to 5,000 years ago when people started to kiss each other.
The World Health Organization (WHO) says that herpes is a common virus that an estimated 3.7 billion people under the age of 50 in the world have a life-long infection of the HSV-1. Despite that, little is known about the history of the virus and how it spread throughout the world.
Great Migration From Eurasia to Europe Helps Spread HSV
The team screened the DNA from the teeth of hundreds of people in ancient archaeological finds and found that four of them had the virus when they died. Christiana Scheib, the study co-author from Cambridge University, said that the team sequenced these reconstructed genomes and found variations of modern strains of the virus from 5,000 years ago.
According to AFP News Agency via Yahoo! News, the origin of the modern strains could be traced back to some time in the late Neolithic to the early Bronze Age. It was a bit surprising find as scientists previously assumed that the herpes simplex virus co-evolved with humans for a very long time.
Scheib added that although all primates have a form of herpes and humans likely had a strain when they first left Africa, earlier forms were replaced by the modern form at the time of the great migration from Eurasia to Europe that could have helped spread the virus.
Moreover, it was around that time as well when people started romantically kissing each other. Scheib said that the theory explains another way to change the transmissibility of the herpes simplex virus to another individual.
The virus is typically transmitted by a parent to their child and researchers believe that kissing would have created a new way for the virus to jump hosts, citing textual evidence that shows in the Bronze Age of kissing between romantic partners.
Herpes History
Despite popular belief, kissing is not universal in humans since there are cultures that have no place for such acts. According to Psychology Today, this suggests kissing is not innate or intuitive as it may seem.
Some thought of kissing as a learned behavior that evolved from "kiss feeding" or the process in which mothers of some cultures feed their baby by chewing their food first and passing it from mouth to mouth. Meanwhile, others believe it could be a culturally determined form of grooming behavior that complement penetrative intercourse.
The earliest evidence of kissing is India's Vedic Sanskrit texts from 3,500 years ago that talk about kissing and the Kama Sutra. Some anthropologists suggest that the Greeks learned about erotic kissing from the Indians when Alexander the Great invaded the country in 326 BCE. However, this does not necessarily mean that kissing started in India.
Researchers used this information to argue that the custom of kissing may have also migrated from Eurasia into Europe. They believe that it is definitely linked to the spread of HSV-1. Even 2,000 years ago, Roman Emperor Tiberius banned kissing at official functions to prevent the spread of the virus.
Charlotte Houldcroft, the co-senior study author of the study, said that the herpes simplex virus and other viruses alike evolved on a "far grander timescale" than COVID-19. However, the mutation is slower because the virus can only be transmitted via oral contact.
Check out more news and information on Herpes Simplex Virus in Science Times.
