Chlamydia infection and testing by Ray Sahelian, M.D.
October 4 2015


Chlamydia is the most common bacterial STD in the U.S., with teenagers and young adults at greatest risk. The infection frequently causes no symptoms, but in women it can lead to long-term complications like pelvic inflammation and fertility problems. There are an estimated 7 million cases of trichomoniasis each year in the U.S compared with about 3 million new cases of Chlamydia and 700,000 cases of gonorrhea.


Risk factors
A higher likelihood of getting this infeciton include preceding human papillomavirus, smoking, and substance use, which may reflect both biological and behavioral mechanisms of risk such as immune modulation, higher-risk sexual networks, or both.

Chlamydia Symptoms
Chlamydia trachomatis infection most commonly affects the urogenital tract. In men, the infection usually is symptomatic, with dysuria and a discharge from the penis. Untreated chlamydial infection in men can spread to the epididymis. Most women with chlamydial infection have minimal or no symptoms, but some develop pelvic inflammatory disease.


Chlamydia in Newborns and Children

A chlamydia infection in newborns can cause ophthalmia neonatorum. Chlamydial pneumonia can occur at one to three months of age, manifesting as a protracted onset of staccato cough, usually without wheezing or fever.


Chlamydia Treatment and during pregnancy
Treatment options for uncomplicated urogenital infections include a single 1-g dose of azithromycin orally, or doxycycline at a dosage of 100 mg orally twice per day for seven days.

The recommended treatment during pregnancy is erythromycin base or amoxicillin. A history of diagnosed chlamydia  infection is associated with an increased risk for ectopic pregnancy.


Health Insurance
Young U.S. adults with health insurance are less likely than their uninsured counterparts to have the sexually transmitted disease chlamydia. Young people with health insurance are more likely to get regular screening and treatment with antibiotics, which would also keep them from spreading the infection. They may also simply be more aware of chlamydia and how to lower their risk.

Chlamydia Screening

The Centers for Disease Control and Prevention and the U.S. Preventive Services Task Force recommend screening for chlamydia infection in women at increased risk of infection and in all women younger than 25 years. However, in a 2015 study, annual chlamydia screening failed to show significant benefit.


A rapid urine test for chlamydia identified 84 percent of infections in men, offering a quick and painless way to diagnose the common sexually transmitted disease, according to Dr. Helen Lee from the University of Cambridge, who developed the test. Dr. Henlen Lee is president and chief executive of Diagnostics for the Real World in Sunnyvale, California, a university spin-off company that is commercializing the test. July 2009.