More than 846million adults worldwide are currently living with genital herpes, according to the latest global estimates.
Genital herpes is an exceedingly common and life-long sexually transmitted disease spread by two types of the herpes simplex virus (HSV).
Both types one and two can cause genital herpes. Type one, which can occur at a young age, typically causes oral herpes (manifested as cold sores), while HSV-2 is generally associated with sexual transmission and genital herpes.
An international team of researchers sought to improve upon earlier methods to estimate the prevalence of both types of HSV worldwide in people under 50, starting with the World Health Organization’s 2012 and 2016 estimates.
More broadly, the research team determined that two-thirds of the global population – around 3.8 billion people – were living with any form of the more common HSV-1 in 2020.
In 2020 alone, there were 122 million new HSV-1 infections in people from birth to 49 years old, including 16.8 million new genital infections.
And among people 15 to 39 affected by sexually-transmitted HSV-2, researchers identified 26 million new infections in 2020, bringing the total number of people currently living with HSV-2 to 520 million.
Around 20million Americans test positive for sexually transmitted infections every year, a startling statistic experts say is symptomatic of a more significant public health crisis, which has seen rates of some diseases such as syphilis reach historic highs.
Between 50 and 80 percent of Americans get the occasional cold sore, while about 12 percent of Americans 14 to 49 years old have genital herpes.
Genital herpes causes painful blisters and open sores at times on the vagina, penis, labia, or testicles, but it can also be asymptomatic. Additionally, the herpes simplex family of viruses can lay dormant in the body without causing noticeable problems.
When the virus infects a person, it may travel up to a cluster of sensory nerves in the brain and remain dormant there for months or even years after the initial infection.
But in times of stress, severe fatigue, or changes to the immune system, the virus can reactivate, multiply, and travel back to the skin through nerve fibers. These stressful times can result in new blisters in the same area as the initial infection.
The rates of HSV-2 were particularly high among young adults in the Americans and Africa. The incidence of HSV-2 generally decreased with age across both regions, pointing to a higher risk of infection in younger people.
In 2020, approximately 25.6 million new genital HSV-2 infections occurred globally among individuals aged 15 to 49 and 16.8 million new genital HSV-1 infections occurred globally in the same age group.
A total of 122.2 million new HSV-1 infections (acquired orally or genitally) were estimated in people from birth to age 49, with the African region having the highest incidence.
By 2020, around 520 million people 15 to 49 were living with HSV-2 infections and around 376 million people globally were living with genital HSV-1 infections.
Researchers said: ‘In addition to the painful genital sores, genital herpes is associated with a range of social and psychological adverse outcomes, including effects on sexual relations, quality of life, and mental health issues such as depression, anxiety, and low self-esteem.’
Many people with the condition wrestle with thoughts of, ‘my life is over,’ and ‘no one will ever accept me.’ Those feelings of shame may block people for seeking out medical care.
A herpes diagnosis may also influence a woman’s decision to have children, as there is a risk that the virus could be spread to the baby as it’s born, ‘a disabling disease in newborns with a high fatality rate’ if left untreated, according to the researchers.
Genital herpes is also associated with a three-fold increased risk for HIV infection. Scientists believe that the painful lesions account for the higher risk in that they create an ideal environment for the HIV virus to replicate.
People diagnosed with genital herpes are treated with prescription antiviral medications to make outbreaks shorter and less painful, but there is no cure.
While the US in the midst of a protracted epidemic of STIs, researchers behind the latest estimates were cautiously optimistic about their findings, which suggested that the incidence of genital herpes is actually showing signs of decreasing.
They said: 'HSV- 2 global prevalence was virtually equal in the 2016 and 2020 estimation rounds.
‘Considering the shifts in the underlying demography during this time (increase in global average age and the changing proportion of the global population in each region), HSV- 2 prevalence, adjusted for the demographic trends, appears to be slowly declining.’
Their results were published in the journal Sexually Transmitted Infections.
They attributed the positive sign to 'less risky sexual behavior following the HIV epidemic, improved sexually transmitted infection (STI) awareness, increasing access to HIV/STI services,' and/or changes in how people form sexual relationships due to changes in economic and social factors.
