Major Finding: The overall seroprevalence of HSV-2 in a national survey conducted from 2005 to 2008 was 16%, with women and African Americans disproportionately affected.
Data Source: Data gathered from 7,293 participants in the National Health and Nutrition Examination Survey.
Disclosures: Dr. Douglas and Dr. Taylor have no conflicts of interest related to the findings of this study.
ATLANTA — About one in six Americans aged 14-49 years is infected with herpes simplex virus type 2 (HSV-2), and 81% of these individuals are unaware of their infection, according to data presented at a conference on STD prevention sponsored by the Centers for Disease Control and Prevention.
The overall seroprevalence of HSV-2 in a national survey conducted from 2005 to 2008 was 16%, with women and African Americans disproportionately affected. Rates of infection were almost twice as high in women than in men (21% vs. 12%) and were more than three times higher in African Americans than in whites (39% vs. 12%). The population most affected was African American women, who had a herpes prevalence of 48%.
“As stark as these disparities are, they are not substantially different from CDC's previous estimates of these populations,” said the lead study author, La'Shan Taylor, Dr. P.H., an Epidemic Intelligence Service officer at the CDC.
These estimates, based on data gathered from 7,293 participants in the National Health and Nutrition Examination Survey (NHANES), indicate that the prevalence of HSV-2 has remained stable since the 1999-2004 estimate of 17%, which had followed a decreasing trend in herpes prevalence that had occurred in the last decade, down from 21% in 1988-1994.
The prevalence of HSV-2 increased with age, from 1.4% among 14- to 19-year-olds to 26% among 40- to 49-year-olds, reflecting the lifelong, incurable nature of the infection. Those with a higher number of lifetime sex partners were also more likely to have HSV-2 infection, with the prevalence ranging from 4% among those with 1 lifetime sex partner to 27% in those with 10 or more reported partners.
Regarding the gender and ethnic disparities in herpes prevalence, Dr. Taylor explained that biological factors among women may increase their susceptibility to HSV-2 infection, and that complex social, biological, and environmental factors could contribute to the higher HSV-2 prevalence among African Americans. “Once this disparity exists, herpes infections are likely perpetuated because of the higher prevalence of infections within black communities,” she said.
Dr. John M. Douglas, director of CDC's Division of STD Prevention, commented that the high prevalence of herpes in African Americans is particularly concerning given the linkage between HSV-2 infection and HIV. Studies have shown that individuals with genital herpes are two to three times more likely to acquire HIV infection. Moreover, among HIV-infected individuals, HSV-2 coinfection increases the likelihood of transmitting HIV. Dr. Douglas suggested that the high rates of genital herpes among African Americans might be contributing to the high rates of HIV in this population.
He added that herpes can cause symptoms other than genital sores, including redness or burning in the genital area that can be mild or mistaken for another condition. Visible sores are not necessary for transmission; individuals with no visible sores or symptoms can still transmit the infection. Thus, “many individuals are transmitting herpes to others without even knowing it.”
While the CDC does not recommend routine HSV-2 screening for the general population, Dr. Douglas and his colleagues said that testing may be useful in at-risk populations, such as those with multiple sex partners, HIV-positive individuals, and gay and bisexual men.
“We can't afford to be complacent about this infection,” concluded Dr. Douglas.