Definition
Primary Herpes Simplex Virus (HSV) Infection
- First infection with either herpes simplex virus-1 (HSV-1) or herpes simplex virus-2 (HSV-2) in individuals who do not have antibodies to either HSV-1 or HSV-2
First Episode - Non-primary Infection
- Infection with either HSV-1 or HSV-2 in individuals who have previously existing antibodies against HSV-1 or HSV-2 respectively
Recurrent HSV Infection
- Results from reactivation of latent virus
- Usually brought about by triggering factors (eg ultraviolet [UV] light, immunosuppression, trauma, stress, febrile illness)
- Less severe and becomes less frequent with time
Epidemiology
- Globally, HSV-1 infection affects approximately 3.8 billion individuals under 50 years of age and approximately 519.5 million in 15- to 49-year-old individuals are infected with HSV-2
Transmission
- Direct contact with sores, saliva or areas around the mouth of actively shedding individuals encourage transmission of HSV-1; incubation period ranges from 2-12 days
- HSV-2 virus is typically transmitted during sexual intercourse through direct contact of genital or anal surfaces, skin, sores or fluids