Risk Factors

Although the prevalence of genital herpes is declining in the United States, it still remains in epidemic proportions. According to the U.S. Centers for Disease Control and Prevention (CDC), at least 45 million Americans ages 12 and over have had genital herpes. About 1 in 5 adolescents and adults are infected with genital herpes.

Genital herpes is most commonly spread by genital-to-genital or oral-to-genital contact during the days preceding an outbreak (the prodrome period).

Gender. Anyone who is sexually active is at risk for genital herpes, and it is on the rise. Studies indicate that around 22% of Americans are infected with HSV-2, with the risk higher in women (26%) than in men (18%). Men, however, have twice as many recurrent infections as women.

Women have an 80 - 90% chance of contracting HSV-2 after unprotected sexual activity with an infected partner and are 4 times more likely to be infected than men. In one study of sexually active American adolescents, 15% of the females had evidence of being infected with HSV-2, compared to none of the males. Having a drinking problem greatly increased the likelihood of infection in these young women.

Ethnicity. Although African Americans are more likely to test positively for HSV-2, Caucasians have a higher risk for active genital symptoms, and over the past few years the greatest increase in HSV-2 has been observed in white adolescents.

Compromised Immune Systems. People with compromised immune systems, notably patients with HIV, the virus that causes AIDS, are at very high risk for HSV-2. Between 68 - 81% of patients with HIV are infected with HSV-2. Such patients are also at risk for more severe complications from herpes. Other immunocompromised patients include those taking drugs that suppress the immune system and transplant patients.

Individuals at Risk for Specific Forms of Herpes

The following are examples of groups that are at particularly risk for specific forms of herpes.

• Health care providers, including doctors, nurses, and dentists. This group is at higher than average risk for herpetic whitlow, which is herpes that occurs in the fingers.
• Wrestlers, rugby players, and other athletes who participate in direct contact sports without protective clothing. These individuals are at risk for herpes gladiatorum, an unusual form of HSV-1 that is spread by skin contact with exposed herpes sores and usually affects the head or eyes.