Incurable, 'highly contagious' STD affects nearly 900 million people under age 50

The prevalence of one uncurable STI in particular - genital herpes simplex virus (HSV) type 1 and 2 - is at a global high, according to a new study published in the BMJ Journals Sexually Transmitted Infections.

Approximately 846 million people between 15 and 49 years old (more than one in five) were living with a genital herpes infection as of 2020.

The World Health Organization (WHO) confirmed that at least one person each second, amounting to 42 million people annually, is estimated to acquire the infection.

The infection can lead to painful genital sores and blisters that typically recur in random episodes throughout life. In 2020, more than 200 million people in the same age group suffered at least one painful symptomatic episode, data shows.

Not every case of HSV is symptomatic, which makes transmission more likely.

The researchers concluded that the "high incidence and prevalence" of HSV worldwide requires new prevention and treatment measures, such as vaccines, to control the spread and reduce the disease burden.

Study co-author Laith Abu-Raddad, a health care policy and research professor at Weill Cornell Medical College in Qatar, emphasized the scale of HSV's impact.

"Symptomatic genital herpes imposes a substantial global burden, affecting 200 million people annually and incurring significant economic costs, estimated at $35 billion per year due to health care expenditures and productivity loss," he wrote in a statement to Fox News Digital. 

"Developing a vaccine capable of protecting against HSV-1 and HSV-2, the viruses responsible for genital herpes, represents a pivotal step toward controlling this infection on a global scale."

There is currently no cure for HSV, although there are treatments to help manage symptoms.

Dr. Gabe Gaviola, senior medical director at Everlywell in New York - an at-home STD testing and treatment platform - shared his concern about increased exposure.

"There's also a persistent stigma associated with genital herpes, which may discourage individuals from seeking treatment or disclosing their herpes status to partners, leading to further spread."

"High prevalence rates, especially in individuals aged 15 to 49 years old, are driven by a lack of public awareness, prevention efforts, and access to testing and treatment," he said.

"Safer sex practices, including condom use and antiviral treatments for those who have HSV, can help reduce the transmission of HSV," he added.

While HSV outbreaks can be controlled and potentially become less frequently or severely over time, flare-ups can occur during times of stress or illness, according to Gaviola.

HSV remains dormant in nerve cells after initial infection, which makes it "extremely difficult to completely eradicate from the body," he said.

"It can reactivate at any time, often without warning," he warned. "This dormancy also allows the virus to evade the immune system, which prevents the body from eliminating the infection."

"Public health measures to reduce transmission and improve treatment are critical in managing the global burden of HSV."

Anna Wald, M.D., professor of medicine, laboratory medicine and epidemiology at the University of Washington, noted that the nature of the herpes virus, much like chickenpox and shingles, makes the development of a cure difficult - although early, preclinical trials are underway. 

"[A] cure is likely to require gene therapy, which is a potentially risky approach for a non-lethal disease," Wald, who was not involved in the research, told Fox News Digital. "So progress is slow as a result."

"Testing vaccines for prevention is very expensive, but there are some new candidate vaccines that will hopefully be in trials in the next few years," she shared.

"In my opinion, a preventative vaccine would be an optimal approach, but we don't yet know how to make one that will work - and testing them is a lengthy and costly process."