March 8, 2004 (Philadelphia) -- Defying previous research -- and popular belief -- that chlamydia affects women far more often, a new study indicates that America's most common bacterial sexually transmitted disease occurs nearly as frequently in men.
Chlamydia was found in 9% of 1,300 men between ages 12 and 24 who were tested by the Minnesota Department of Health over a two-year period. That is nearly as high as the 11% prevalence rate among similarly aged women in that state. Nationally, about 3 million new cases are diagnosed each year.
But this new research, unveiled Monday at the 2004 National STD Prevention Conference, suggests that more efforts should be placed on screening men -- and possibly on developing new strategies to combat this bacterial infection.
"The single biggest indicator -- more than whether or not men had unprotected sex -- was their number of sexual partners," researcher Nicoline Collins Tablan, MPH, tells WebMD. "Young men who had at least three sexual partners in the previous six months were four times more likely to test positive as those with fewer partners."
More Women Screened
Historically, chlamydia screenings are more likely to be done on women because about one in three cases results in pelvic inflammatory disease (PID), causing serious infection or inflammation in a woman's uterus, fallopian tubes, or ovaries. PID increases a woman's later risk of infertility or ectopic pregnancy, a potentially dangerous condition in which the fertilized egg attaches to an area outside the womb. In men, however, chlamydia rarely causes any serious damage or long-lasting effects, and although it can cause discharge from the penis, most men with chlamydia are unaware of their infection.
In both men and women, chlamydia can be treated with a single dose of antibiotics.
The reason why men aren't routinely screened for chlamydia, which they may pass onto their partners, often comes down to a question of dollars and cents, says one expert not involved in Talban's research.
"The problem is, chlamydia doesn't affect men in the same way as women," says John M. Douglas Jr., MD, director of the CDC's STD Prevention Programs. "The feeling has been, it's not as cost-effective to screen men."
Even so, only about 25% of women are routinely screened for chlamydia - likely because many doctors are too busy to take complete sexual histories of their young, sexually active patients, especially when they display no symptoms.
"The glass is only about one-quarter full," Douglas says. "The glass needs to be more full."
More Awareness, Programs
But in recent years, several innovative programs have been started to screen more sexually active teens for chlamydia, with hopes of reducing its potentially devastating effects in women.
For instance, a chlamydia screening program for sexually active Philadelphia public school students revealed that nearly 9,400 girls were infected. Officials calculated that because they were screened and treated with antibiotics, the early intervention prevented some 200 later cases of PID. A similar program in a Detroit suburb found that 18% of teens were infected, most of whom wouldn't have known it.
And three years ago, California became the nation's first state to initiate a program in which doctors and other health care providers administered antibiotics for chlamydia and other STDs to both patients and their partners -- knowing that partners, and in particular males, might be hesitant to see a doctor on their own. Since then, half of 2,000 doctors and 1,800 nurse practitioners surveyed say they "always" or "usually" provide medication to the partners of their patients.