THURSDAY, Sept. 25, 2014 (HealthDay News) -- An estimated 1.8 million Americans aged 14 to 39 are infected with the sexually transmitted disease chlamydia, and many don't know it, federal health officials reported Thursday.
Rates of infection are highest among young women. An estimated 4.7 percent of women aged 14 to 24 were infected with the easily treated disease in 2012, which often has no symptoms. But, if left untreated, chlamydia can lead to infertility, problems during pregnancy and other health threats.
"Chlamydia is common, and it's especially common in young women. Most young women who are infected don't know they have it," said study author Elizabeth Torrone, an epidemiologist with the U.S. Centers for Disease Control and Prevention's division of STD prevention.
"This report really underscores the need for young women to be screened for chlamydia annually," she said.
The report was based on statistics from the 2007-2012 National Health and Nutrition Examination Survey.
Infection rates were highest among black women aged 14 to 24 -- at 13.5 percent. Among Mexican-American women, the rate of infection was 4.5 percent. And among white women, it was 1.8 percent, according to the study.
The overall prevalence of chlamydia among those aged 14 to 39 has remained virtually unchanged for nearly a decade, according to the report. From 2007 to 2008, the infection rate was 1.6 percent; from 2009 to 2010, it was 1.7 percent; and from 2011 to 2012, it was 1.9 percent.
Chlamydia is easily diagnosed with a urine test, and it is easy to treat with antibiotics, Torrone said. She added that it's important that the partners of infected women be treated, too.
Dr. Metee Comkornruecha, an adolescent medicine specialist at Miami Children's Hospital, said the findings "line up with what we are seeing."
If the infection is caught early, it is usually cured with a single dose of an antibiotic, Comkornruecha said. If the infection has spread, however, the treatment may require two weeks of antibiotics or, in some cases, stronger intravenous antibiotics, he said.
The U.S. Preventive Services Task Force recommends that all sexually active women under the age of 25 be screened yearly for chlamydia, Torrone said.
A woman's risk for infection decreases as she ages, according to the report. It was published in the Sept. 27 issue of the CDC's Morbidity and Mortality Weekly Report.
To learn more about chlamydia, visit the U.S. Centers for Disease Control and Prevention.