It’s a problem that plagues an estimated 3.7 billion people worldwide, and now scientists have uncovered the history — or should we say “kiss story” — of cold sores.
Researchers at the University of Cambridge have mapped ancient genomes of herpes – the virus that often causes lip sores.
Their findings suggest that the strain of the virus behind facial herpes as we know it arose about 5,000 years ago, amid the advent of “sexual-romantic kissing.”
dr. Christiana Scheib, co-senior author of the study, said: “Every species of primates has some form of herpes, so we assume it’s been with us since our own species left Africa.
“However, something happened about 5,000 years ago that allowed one herpes strain to overtake all the others, possibly an increase in transmissions, which could be linked to kissing.”
It’s a problem that plagues an estimated 3.7 billion people worldwide, and now scientists have unraveled the history – or should we say ‘kiss story’ – of cold sores.
In the study, the team extracted viral DNA from the teeth of four people. One sample (pictured) was from a young adult male from the Netherlands and dates to 1672
The strain of the virus that is common today is called HSV-1 and is usually transmitted through oral-to-oral contact, such as kissing.
‘Cold sores are caused by a virus called herpes simplex,’ explains the NHS on its website.
“Once you have the virus, it stays in your skin for the rest of your life. Sometimes it causes cold sores.
“Most people are exposed to the virus at a young age after close skin-to-skin contact, such as kissing, with someone who has a cold sore.”
Although the herpes virus is millions of years old, the researchers wanted to understand when the HSV-1 strain first emerged.
“The world has seen COVID-19 mutate at a rapid pace for weeks and months. A virus like herpes evolves on a much larger time scale,” said Dr. Charlotte Houldcroft, co-senior author of the study.
‘Facial herpes hides for life in its host and is only transmitted through oral contact, so mutations occur slowly over centuries and millennia.
‘We need to do in-depth research to understand how these types of DNA viruses develop.
“In the past, genetic data for herpes didn’t go back until 1925.”
In the study, the team extracted viral DNA from the teeth of four people.
The oldest sample dates back to about 1,500 years and comes from an adult male unearthed in the Ural Mountains in Russia.
Another dates to the 6-7th century CE and came from a woman from an early Anglo-Saxon burial ground near Cambridge.
One sample dates back to the late 1400s and came from a young adult man buried in the grounds of the Cambridge Charity Hospital
The third dates from the late 14th century and came from a young adult man buried in the grounds of the Cambridge Charity Hospital.
And finally, one sample came from a young adult man from the Netherlands and dates back to 1672.
After extracting the viral DNA, the researchers compared their results with herpes samples from the 20th century.
This allowed them to analyze differences and estimate a mutation rate, creating a timeline for the evolution of the virus.
The findings suggest that HSV-1 first emerged about 5,000 years ago.
According to the researchers, the earliest known mention of kissing is in a Bronze Age manuscript from southern China.
They suggest that the custom then traveled west when people migrated to Europe from Eurasia.
“The primary mode of HSV-1 transmission is vertical, parent-to-child,” the team wrote in their study, published in Science Advances.
The addition of lateral transfer as population density increased during the Bronze Age, possibly coupled with the introduction of new cultural practices such as the advent of sexual-romantic kissing, may have contributed to a shift in the dominant sexes, which have continued to grow until the late 1990s. circulate today.’
Although HSV-1 usually causes cold sores alone in most people, it can be fatal when worn in conjunction with other conditions, such as sepsis.
In 2018, for example, two women died of an HSV-1 infection in the UK following a cesarean section.
The team now hopes to trace HSV-1 even deeper through time.
“Neanderthal herpes is my next mountain to climb,” added Dr Scheib.