Around one in five of the world’s under 50s are living with genital herpes infection, according to estimates published in a new global study.
That means that around 846 million people worldwide are thought to be living with the incurable sexually transmitted infection (STI). The research, published online in the journal Sexually Transmitted Infections, suggested that more than 200 million 15 to 49 year olds probably had at least one symptomatic outbreak of the STI in 2020 - the latest year for which figures are available.
The findings have prompted the researchers to call for the development of new treatments and vaccines to control the spread of the infection and lessen its health and financial toll. They say that the options currently available have only had a modest impact on people.
**READ NEXT: [UK tourists warned of major change when travelling to Europe in 2025](https://www.manchestereveningnews.co.uk/news/world-news/uk-tourists-warned-major-change-30553031)**
There are 2 types of herpes simplex virus, type 1 (HSV-1) and type 2 (HSV-2), both of which are highly infectious and incurable - so last a lifetime. HSV-1 is primarily spread in childhood by mouth contact, resulting in ‘cold sores’ in or around the mouth. But it is increasingly being spread through sexual contact at older ages, say the researchers.
And it can sometimes cause more serious neurological, eye, skin and mucous membrane complications.
Meanwhile, HSV-2 is almost entirely sexually transmitted through skin to skin contact and is the leading cause of recurrent painful genital blisters. Although rare, both HSV-1 and HSV-2 can be passed from a pregnant woman to her baby during pregnancy or delivery, which can prove fatal.
The researchers, from Weill Cornell Medicine in Qatar, Doha, incorporated a series of recent comprehensive systematic reviews and pooled data analyses published up to March 2022 in a bid to update previous estimates of the global incidence and prevalence of genital HSV infection. They also used mathematical modelling to estimate the global and regional incidence and prevalence of genital HSV infection and related symptoms in 2020.
Based on the available data, the researchers estimated that, across the globe, 26 million 15 to 49 year olds were newly infected with HSV-2 infection. Meanwhile, an estimated 520 million had an existing infection - just over 13% of those in this age group.
An estimated 17 million 15 to 49 year olds acquired HSV-1 infection genitally, and an estimated 376 million - 10% of those in this age group - had an existing infection in 2020.
Researchers have called for the development of new treatments and vaccines to control the spread of genital herpes infection (Image: Getty Images/Cavan Images RF)
In all, two-thirds of the global population up to the age of 49—-nearly 4 billion people—-were infected, mostly orally, with HSV-1 in 2020, the researchers estimated.
The researchers estimated that the total global numbers of new and existing HSV infections among 15 to 49 year olds in 2020 were 42 million and 846 million, respectively.
The researchers acknowledged some limitations to their findings, including the scarcity of data for people at either end of the age spectrum, and relatively wide ranges for some of their estimates.
But they concluded: “HSV infections are widely prevalent in all global regions, leading to a significant burden of genital ulcer disease with repercussions on psychosocial, sexual, and reproductive health, neonatal transmission, and HIV transmission. However, hardly any specific programmes for HSV prevention and control exist, even in resource-rich countries.”
They add: “There is a need for HSV prophylactic and therapeutic vaccines as a strategic approach to control transmission and to curb the disease and economic burdens of these infections.”