WebMD Health News
Brunilda Nazario, MD
July 17, 2007 -- More than 2 million people in the U.S. are infected with
chlamydia and 250,000 have gonorrhea, according to a government prevalence
estimate for the two sexually transmitted diseases.
Rates of both STDs were disproportionately high among adolescents and
African-Americans and among people who had been previously infected with
chlamydia or gonorrhea.
The findings present the most comprehensive snapshot of chlamydia and
gonorrhea infection in the U.S. ever reported, CDC medical epidemiologist S.
Deblina Datta, MD, tells WebMD.
CDC researchers studied 6,632 people between the ages of 14 and 39
participating in a national health survey from 1999-2002. All the participants
provided urine samples, which were tested for the presence of chlamydia and
"We confirmed that both chlamydia and gonorrhea still pose significant
health risks in the United States and that disparities exist, especially with
regard to the prevalence of gonorrhea among whites and blacks," Datta
Of the diseases that by law must be reported to government health officials,
chlamydia and gonorrhea respectively rank No.1 and No. 2 in incidence.
While symptoms can include painful urination, abdominal pain, and unusual
discharge from the vagina or penis, many people with chlamydia or gonorrhea
have no symptoms at all.
In women, untreated chlamydia or gonorrhea infection can cause pelvic
inflammatory disease, infertility, and pregnancy complications such as
low-birth-weight babies, premature birth, and serious infections in
Treatment with antibiotics is important to prevent these and other
complications and avoid spreading the STDS, but many people don't get treated
because they don't know they are infected.
According to the newly published CDC estimate, two out of every 100 (2.2%)
adolescents and adults under age 40 in the U.S. are infected with chlamydia and
just under one in 400 (0.24%) have gonorrhea.
Across all ethnic groups, adolescents and young adults had the highest
infection rates and roughly half of those with gonorrhea infections also had
Overall, the prevalence of chlamydia infection was similar among men and
women. But the infection rate was roughly four times higher for
African-Americans than for whites (6.4% vs. 1.5%) and the disparity was even
higher for gonorrhea.
The chlamydia rate was 17% for females who had reported a previous chlamydia
or gonorrhea infection within the past year.
CDC currently recommends annual chlamydia screenings for all sexually active
women under the age of 26, and annual screenings for older women with risk
factors for the STD, such as a new sex partner or multiple partners. Screening
is also recommended for all pregnant women.
Routine screening for gonorrhea is also recommended for women with a high
risk for infection, such as sex workers and women with new or multiple sex
The findings suggest that current chlamydia and gonorrhea screening
recommendations are adequate, assuming they are implemented, Datta says.
"If screening recommendations are properly applied they will be
effective, but we know that this isn't happening consistently," she says.
"This needs to be a focus of STD prevention."
The prevalence analysis appears in Tuesday's issue of the Annals of
In a separate study, published in the same issue of the journal, another
group of CDC researchers reported that the prevalence of penicillin-resistant
gonorrhea appears to be declining, while resistance to antibiotics in the class
known as fluoroquinolones is on the rise.
In April of this year the CDC recommended that fluoroquinolones no longer be
used to treat the infection because of rising resistance among both
heterosexual and gay men.
Now only one class of antibiotics -- cephalosporins -- is recommended for
the treatment of gonorrhea.
In a press release, CDC officials noted that the declining treatment options
underscored the need for new drugs to treat the infection and for better ways
to monitor drug resistance.
SOURCES: Datta, S.D. and Wang, S.A. Annals of Internal Medicine, July
17, 2007; vol 14: pp 81-97. S. Deblina Datta, MD, Division of STD Prevention,
CDC, Atlanta. Susan A. Wang, MD, MPH, National Center for HIV/AIDS, Viral
Hepatitis, STD, and TB Prevention, CDC, Atlanta. "CDC Changes
Recommendations for Gonorrhea Treatment," April 12, CDC press release.
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