Oral and genital herpes are two of the most common types of viruses that affect humans. New research says the two are constantly mixing, potentially presenting a new challenge to public health.
2 Types Of Herpes
HSV-1 typically affects the mouth, while HSV-2 affects the genitals, so it's clear that while the two look alike, the two types of herpes are genetically very different.
In a new study published in the Journal of Infectious Diseases, a team of researchers reveals evidence that the two human herpex simplex viruses HSV-1 and HSV-2 are mixing genetic material. This results in new, different recombinant herpes versions.
"The main implication is that HSV-1 and HSV-2 are continuing to recombine," explained Dr. Amanda Casto, lead author and a senior fellow in infectious diseases at the University of Washington School of Medicine, in a news release from the university. "This could have important implications for HSV vaccine development, because it means a live HSV-2 vaccine could recombine with circulating HSV-1 strains, thereby forming an infectious virus."
The two types of the herpes virus diverged from one virus 6 million years ago, when humans diverged from chimps. When HSV-2 began affecting humans again 1.6 million years ago, humans found themselves vulnerable to two types of herpes simplex viruses.
In ancient times, there's evidence of HSV-1 and HSV-2 recombining, mixing their genetic material together. The new study shows that recombination of the two still occurs more often than previously believed in modern times.
As Dr. Alex Greninger, one of the study authors, put it in an interview with Live Science, the two types of herpes virus are still "having sex" at present.
Specifically, the HSV-2 virus has been found acquiring genes from HSV-1, which results in the genital herpes virus continuing to evolve. With HSV-1, which usually affects the mouth, causing more genital infections in recent years, the opportunity for more co-infections between HSV-1 and HSV-2 is growing.
What Does This Recombination Mean For The Public?
The continuous evolution of HSV-2 could have negative implications, such as the possibility of the virus developing resistance to current medication.
Greninger added that it could also make the development of herpes vaccine more difficult for scientists. For instance, if a vaccine is created for HSV-2, the virus could exchange some of its genes to avoid getting affected by the vaccine.
Of course, no vaccine has been developed to combat herpes as of yet.
"Herpes is one of the most stigmatized diseases out there, and yet it affects billions of people," said Greninger. "We really need more work to combat this virus."