There may soon be a vaccine to protect against genital herpes thanks to Perelman School of Medicine at the University of Pennsylvania researchers. The vaccine the team developed was tested on guinea pigs and mice with fantastic results, better than any other trial yet. The immunization led to “mostly sterilizing immunity” from the virus, which is the strongest type of immunity there is! Sterilizing immunity prevents virus infection into a host. The study has been published in Science Immunology.
Herpes simplex virus type 2 (HSV-2), typically known as genital herpes, is the most common sexually-transmitted disease in the world. Approximately 11% of people aged 14 to 59 globally are infected. The condition may cause painful sores to pop up and spread to other areas of the body. What’s most dangerous is that the virus increases the risk of contracting HIV. Furthermore, a mother can pass herpes onto her unborn child as a fetus or to the baby during delivery.
However, the physical symptoms are only part of the suffering. There is also an emotional toll. The study’s principal investigator Harvey Friedman, MD, a professor of Infectious Diseases, said:
Along with physical symptoms, HSV-2 takes an emotional toll. People worry over transmission of the disease, and it can certainly have a negative effect on intimate relationships.
The Study With Mice
- The Penn-developed vaccine was delivered to 64 mice.
- The mice were then exposed to genital herpes.
The Results
- Sixty-three of the mice were found to have sterilizing immunity after testing them 28 days later. They had no trace of herpes infection or disease even after being exposed to the virus.
- The one mouse that did get herpes developed a dormant infection.
The Study With Guinea Pigs
- The vaccine was delivered to 10 guinea pigs.
- The animals were then exposed to genital herpes.
The Results
- None of them developed genital lesions.
- Two showed evidence of becoming infected but the infection was of a non-transmittable form.
Conclusion
A successful vaccine would be invaluable to so many people around the world because the virus is only visible during an outbreak but can be transmitted even if it’s undetected. Since so many people have it, it can be easy to catch it.
Friedman said:
We’re extremely encouraged by the substantial immunizing effect our vaccine had in these animal models. Based on these results, it is our hope that this vaccine could be translated into human studies to test both the safety and efficacy of our approach.
The approach to how the vaccine works is similar to that of many cutting-edge cancer and immunotherapy treatments. The researchers filled the vaccine with specific messenger RNA that create proteins needed for a robust immune response. Their vaccine differs from other herpes vaccines because it doesn’t only block the virus’ entry; it also ensures that the virus can’t “turn off” innate immune system protective functions.
Next, they plan to make a vaccine for other herpes (cold sore) viruses as well.
