March 9, 2010 -- One in six Americans between the ages of 14 and 49 have genital herpes and close to one in two black women are infected, new figures from the CDC reveal.
Rates of infection with herpes simplex virus type 2 (HSV-2) -- the sexually transmitted virus that causes most genital herpes -- have remained relatively stable over the last decade, following steep declines in infection rates in the late 1980s and early 1990s.
About 19 million people in the U.S. are infected with HSV-2, at a cost to the nation’s health care system of close to $16 billion a year.
Overall, 16% of Americans between the ages of 14 and 49 had genital herpes between 2005 and 2008, compared to 17% between 1999 and 2004.
The new estimates come from the CDC’s National Health and Nutrition Examination Survey (NHANES), which is a nationally representative survey of U.S. households covering a wide range of health issues.
According to the latest findings:
- Women and African-Americans were the most likely to be infected. HSV-2 prevalence was nearly twice as high among women (21%) as men (11%), and more than three times higher among African-Americans (39%) than whites (12%).
- The infection rate among African-American women was 48%
- The infection rate was roughly 4% among people who reported having just one sex partner ever, compared to almost 27% for those who reported 10 or more partners.
- Nearly four out of five people who have genital herpes have not been diagnosed and may not know they have the infection.
Genital Herpes Raises HIV Risk
"This latest analysis emphasizes that we can’t afford to be complacent about this infection," John M. Douglas, Jr., MD, who directs the CDC’s Division of STD Prevention, said in a news conference Tuesday at the 2010 National STD Prevention Conference in Atlanta.
"It is important that we promote steps to prevent the spread of genital herpes, not only because herpes is a lifelong and incurable infection, but also because of the linkage between herpes and HIV infection."
Research shows that people with genital herpes are two to three times more likely to acquire HIV and they are also more likely to transmit HIV infection to others.
Douglas explained that the immunologic response at the site where herpes ulcers form act as a target for HIV infection even after the ulcers have disappeared.
"If you come into contact with the HIV virus, even after the ulcers have healed, you may be more likely to become infected," he says.
People who are dually infected with HIV and HSV-2 may also be especially likely to transmit the HIV virus to others during genital herpes flare-ups.
Need for Increased Public Awareness
The reason women have higher rates of HSV-2 infection than men is largely explained by the fact that their genital tissue is more vulnerable to the small tears that make transmission more likely.
And since the background rate of infection is so high in the black community, African-American women are especially at risk, Douglas said.
"It is quite clear that this increased rate of infection in African-American women is not due to increased risk behavior," he said.
The CDC does not recommend routine screening for genital herpes, but testing is recommended for those considered at high risk for getting and transmitting the virus, including people with multiple sex partners. Testing is also recommended for gay and bisexual men and people who are HIV positive.
While the infection cannot be cured, treatments that lessen the severity of genital herpes outbreaks or that may help prevent them are available.
But since most people don’t even know they have the infection, treatment rates are low, says Kevin Fenton, MD, PhD, who directs the CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention.
"Given everything we know about how to prevent, diagnose, and treat STDs, it is unacceptable that STDs remain such a widespread public health problem in the U.S. today," he says.
Douglas said collaboration between public and private-sector groups will be needed to increase public awareness about genital herpes.
He cited the "Get Yourself Tested" STD education campaign as an example. The campaign is directed at teens and young adults and is a partnership between the CDC, the television network MTV, and the philanthropic group Kaiser Family Foundation.
"Public programs alone won’t be able to get the job done, particularly in light of the increasingly tight budgets that so many local and state health departments are facing," Douglas says. "We will need to be more creative in our collective approach to STD prevention."