Three out of four infected women -- and one in two infected men -- don't get early symptoms. But this doesn't mean it just goes away.
Two of five infected women will go on to develop pelvic inflammatory disease, or PID. PID means infertility 20% of the time; debilitating chronic pelvic pain 18% of the time; and a life-threatening tubal pregnancy 9% of the time. It can make men sterile, too. And if a woman with chlamydia does become pregnant, she has up to a 50-50 chance of passing it on to her newborn child. Infants can die or become blind as a result.
"PID is very serious," says Kimberly A. Workowski, MD, FACP, chief of the guidelines unit of the CDC's Division of STD Prevention and associate professor of medicine at Emory University, in Atlanta. "The issue is to screen women and detect chlamydia before serious complications develop."
A Reservoir of Chlamydia
That sounds easy, but the numbers tell a different story. In 2000, the CDC had 379,078 reported cases of chlamydia infection. By the end of July 2001, improved screening led to 362,229 reported cases. These reports usually mean a case that has been detected and cured -- in other words, the tip of the iceberg.
"Part of problem is there is such a reservoir of people out there carrying the infection and not knowing it," says Workowski, frustration evident in her voice. "Treatment is effective. There are good therapies and in fact one medicine that is available can be given in the office so you can watch the patient take it."
The problem is finding people who are at risk and convincing them that their lives -- and those of their loved ones -- are in danger.
Who's at risk? The short answer is, all sexually active people. Since men more frequently get unmistakable early symptoms -- a discharge from the penis, a burning sensation during urination, or swollen testicles -- they are more likely to get treated.
It is young, sexually active women aged 25 and younger who are most at risk. These women, the U.S. Preventive Services Task Force this year advised, should get chlamydia screening as a part of their routine healthcare.
Does screening work? Workowski points to the northwestern states of Oregon, Idaho, Washington, and Alaska.
"They had an initial prevalence rate of 13% [of women aged 15-24] in the late '80s, and now it is less than 5%," she says. "It is due to large-scale screening programs in family-planning clinics. These have proven very effective. Now we need funding to develop the information systems needed to monitor patients for reporting so that case reports go into an automated information system."
The task force also recommended chlamydia screening for pregnant women aged 25 and younger. However, it did not recommend routine screening for all asymptomatic men or for asymptomatic women older than 25 because there is not enough evidence that the benefits of such screening would justify the cost.
Chlamydia: A Bug With a Bite
Chlamydia is a type of bacteria called chlamydia trachomatis. It can infect the penis, vagina, cervix, anus, urethra, and eye. It's sexually transmitted by either vaginal or anal intercourse. Condoms offer partial protection -- they are much, much better than nothing, and they do stop HIV -- but they don't always stop the chlamydia bug.
Unlike most other bacteria, chlamydia can't reproduce itself unless it gets inside human cells. The cells it likes the best are the type that line the urinary and genital tracts of both men and women. These cells, known as columnar epithelial cells, are supposed to keep germs out while allowing fluids to pass through. They are especially plentiful in the lining of the urethra and at the entrance to the cervix. It's here that the bug loves to bite.
Women may not notice the early symptoms of infection, but within five to 10 days of infection they may have bleeding between menstrual periods, painful urination or intercourse, vaginal bleeding after intercourse, low-grade fever, frequent urge to urinate, an inflamed cervix, abnormal vaginal discharge, and even a yellowish discharge from the cervix that may smell bad.
The bottom line? If you're a sexually active man, pay attention to your body. Get tested if you have any symptoms. If you're a sexually active woman 25 or younger, get tested every time you see the doctor.
Natural history studies in the 1970s suggested that many cases of chlamydia go away by themselves. More recent research suggests that this is very unlikely.
"There are studies that show some spontaneous resolution, but do you really want to take that chance?" Workowski asks. "Maybe a couple of percent of people have spontaneous resolutions. We have much more sensitive tests now. The inability [of researchers in the 1970s] to detect chlamydia may have been a problem with the testing they had then."