Every second, someone is getting herpes. That's 42 million people a year

A new study published in the journal Sexually Transmitted Infections reveals that nearly 846 million people worldwide are affected by genital herpes, with more than one in five people aged 15 to 49 living with the infection, according to estimates from the World Health Organization (WHO). The study was authored by experts from WHO, HRP, the WHO Collaborating Centre for Disease Epidemiology Analytics on HIV/AIDS, Sexually Transmitted Infections and Viral Hepatitis at Weill Cornell Medicine-Qatar, and the University of Bristol.

The analysis conducted by doctors showed that 376 million people are carriers of the herpes virus HSV-1, and 519 million are carriers of HSV-2. Of these, 50 million are estimated also to have HSV-2, as it is possible to have both types at the same time. Genital herpes is one of the most common sexually transmitted diseases, with genital HSV-2 accounting for around 90% of symptomatic episodes.

Despite the high prevalence, ninety percent of infected individuals have no or unnoticeable symptoms, making genital herpes extremely difficult to diagnose and track. Many people are blissfully unaware they carry the highly contagious HSV virus and can therefore transmit it without realizing it. Every second, at least one person is infected with the genital herpes virus, corresponding to approximately 42 million new infections per year.

"We urgently need better prevention and treatment to reduce herpes transmission and help reduce HIV transmission," said Dr. Meg Doherty, the World Health Organization's Director of Global HIV, Hepatitis, and Sexually Transmitted Infections Programs.

Dr. Sami Gottlieb emphasized the need for "expanded research and investment in developing new herpes vaccines and therapies," highlighting their potential to improve quality of life for those affected.

There is currently no cure for genital herpes, which means that a case contracted in 2020 can still pose problems years later; however, treatments exist to relieve the symptoms and shorten outbreaks. Available treatments and screening tests have only had a "modest" impact on incidence rates, at best, according to the authors. Antiviral medicines don't work for everyone. While antiviral medicine can somewhat treat these recurrent infections, reducing their length and severity, they can't cure the condition.

Furthermore, stigma around genital herpes means that it is talked about too little, despite affecting millions of people worldwide, and this shame prevents discussion about the disease. Herpes carries a heavy social stigma that makes the infection particularly difficult to study.

"People used to email me all the time asking when a vaccine would be available, saying their lives had been destroyed by the virus. But without interest from pharmaceutical companies, we can't go any farther," explained Akiko Iwasaki, a researcher who has tested possible herpes vaccines.

The authors of the study emphasize that new treatments and vaccines are critically needed to control HSV infections and reduce the associated disease burden. Nevertheless, Harfouche and colleagues say that "hardly any specific programs for HSV prevention and control exist, even in resource-rich countries, partly due to the lack of tools to address such highly prevalent, often asymptomatic, and incurable infections on a population level."

In 2020, an estimated 204 million people annually experienced at least one period of exacerbation of the herpes infection, and more than 200 million people aged 15 to 49 suffered at least one symptomatic episode of genital herpes. In total, that's 205 million people who are possibly suffering from genital sores each year.

Open sores caused by genital herpes allow HIV viruses to enter the body more easily. Genital HSV-2 increases the risk of contracting or transmitting the HIV virus, with open sores allowing HIV to enter the body more easily. WHO recommends that people with symptoms of genital herpes should be offered HIV testing and, if needed, pre-exposure prophylaxis for HIV prevention.

In addition to sores, genital herpes can occasionally lead to serious complications, including neonatal herpes transmitted from a mother to her newborn at birth if the mother is infected late in pregnancy, which can be serious for babies and put their lives at risk. Earlier this year, a new study showed that genital herpes infections not only cause significant health impacts but also major economic costs, amounting to an estimated US $35 billion a year worldwide through healthcare expenditures and productivity loss.

Over recent years, several countries have observed changing patterns of transmission in HSV-1, with adult genital infections increasing as childhood oral infections decline. Reduced oral spread during childhood may be linked to factors like less crowded living conditions and improved hygiene, which then increases susceptibility to the virus at older ages.

Recent evidence suggests the herpes virus might even contribute to dementia later in life if the infection spreads inside the brain, as it is believed that herpes virus fragments enter the brain, causing the formation of protein plaques characteristic of dementia. This year, scientists from Uppsala University in Sweden discovered that people infected with the herpes simplex virus are twice as likely to develop dementia compared to those who have never been infected with this virus.

This article was written in collaboration with generative AI company Alchemiq