Results of a nationally representative study show that genital herpes infection is common in the United States. Nationwide, at least 45 million people ages 12 and older, or one out of five adolescents and adults, have had genital HSV infection. Between the late 1970s and the early 1990s, the number of Americans with genital herpes infection increased 30 percent.

Genital HSV-2 infection is more common in women (approximately one out of four women) than in men (almost one out of five). This may be due to male-to-female transmissions being more likely than female-to-male transmission.