The spread of herpes globally has been merciless with 500 million people already suffering from genital herpes also known as herpes simplex virus 2 (HSV2).

According to a report from Eurekalert, scientists from the Perelman School of Medicine at the University of Pennsylvania are working on a new type vaccine to combat the spread of this disease. It has already proved to be very powerful in trials with standard guinea pig and monkey models of HSV2 infection.

This so-called "trivalent" vaccine targets three different parts of the virus. Many recently-developed vaccines focus on attacking gD2, a glycoprotein that helps the virus get into host cells. The new vaccine is designed to activate antibodies against gD2, but also two other glycoproteins gC2 and gE2, which helps the virus survive longer in the cells.

"It's a novel strategy, and it works beautifully," Harvey M. Friedman, MD, senior investigator and professor of Infectious Diseases at Penn, said. "I know of no other HSV2 vaccine candidate with published results that are as promising as this study."

He explained, "In essence, we're stimulating the immune system to attack the virus and at the same time preventing the virus from using some of the tools it has to thwart that immune attack."

Animal trials were largely successful, exhibiting the potential power of the new vaccine. It sparked antibodies to act against the virus' glycoproteins in macaque monkeys. In a laboratory dish, the vaccine was also able to neutralize the spread of HSV from one cell to another, plus caused an increase in the cells that mobilize antibodies. When the team tested the vaccine on guinea pigs, they found that the creatures were almost completely protected from genital lesions.

"If found effective in clinical trials, the vaccine will have a huge impact on reducing the overall prevalence of genital herpes infections and could reduce new HIV infections as well, especially in high-burden regions of sub-Saharan Africa," lead author Sita Awasthi, PhD, said.

The team and pharmaceutical companies are now discussing moving onto initial clinical trials.

Developing a vaccine for herpes is important because of the disease's impact on public health globally. Aside from the alarming number of people with HSV2, infection also increases the likelihood of HIV transmission. It can also be harmful - even lethal - to the babies of infected mothers.

A report from the World Health Organization (WHO) revealed that HSV2 was highest in Africa, followed by the Americas. Much more women are infected with the disease, because transfer from men to women is more efficient than women to men.