Sexually Transmitted Diseases: Chlamydia: The Most Common STD

Chlamydia: The Most Common STD

Chlamydia trachomatis is the bacterium that causes the most common sexually transmitted disease (STD) in the United States today. It can infect the penis, vagina, cervix, urethra, or eye. The CDC estimates that a staggering four to eight million new cases occur each year. The highest rates of infection are among 15- to 19-year-olds. Symptoms include abnormal discharge (mucus or pus) from the vagina or penis or pain while urinating. Early symptoms may be very mild and usually appear one to three weeks after infection. Often people with chlamydia have few or no symptoms of infection and fail to get treated.

Chlamydia can be transmitted during vaginal, oral, or anal sexual contact with an infected partner. In addition, a pregnant woman may pass the infection to her newborn during delivery, with subsequent neonatal eye infection or pneumonia. Chlamydia can also lead to premature birth or low birth weight.

The bacteria can infect the throat from oral sexual contact with an infected partner. It can also cause an inflamed rectum and inflammation of the lining of the eye (“pink eye”). Complications from chlamydia infections can cause pelvic inflammatory disease (PID), a serious complication that is a major cause of infertility and ectopic pregnancies among women of childbearing age. Each year, approximately 500,000 women in the United States develop PID due to chlamydia infections.

Chlamydia infection is easily confused with gonorrhea because the symptoms of both diseases are similar. Direct culture from the vagina or penis, or from urine, is used to detect the disease. Once diagnosed with chlamydia infection, a person can be effectively treated with antibiotics.

Chlamydia is easy to treat, but both partners must be treated at the same time to prevent reinfection. Antibiotics such as doxycycline, tetracycline, and Zithromax are all effective against chlamydia. Erythromycin is often prescribed for pregnant women and others who cannot take tetracycline.

Potent Fact

Hot Numbers:

CDC National STD Hotline 1-800-227-8922 or 1-800-342-2437 En Espanol 1-800-344-7432 TTY 1-800-243-7889

National Herpes Hotline 919-361-8488

National HPV and Cervical Cancer Hotline 919-361-4848

CDC National Prevention Information Network P.O. Box 6003 Rockville MD 20849-6003 1-800-458-5231 or 1-888-282-7681 Fax 1-800-243-7012

Symptoms for women include:

  • Bleeding between menstrual periods
  • Vaginal bleeding after sex
  • Abdominal pain
  • Painful intercourse
  • A low-grade fever
  • A painful sensation during urination
  • The urge to urinate more than usual
  • Abnormal vaginal discharge
  • A foul-smelling yellowish discharge from the cervix
  • Eye infections

Symptoms for men include:

  • Pus or milky discharge from the penis
  • Pain or burning sensation when urinating
  • Fever
  • Genital Swelling
  • Watery, white, or yellow drip from the penis
  • Extreme pain in the scrotum
  • Eye infections

Chlamydia can spread from the urethra to the testicles causing a condition known as “epididymitis.” Reiter's syndrome, a common type of arthritis due to inflammation of the joints, has also been linked to chlamydia infections in young men.

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Excerpted from The Complete Idiot's Guide to Dangerous Diseases and Epidemics © 2002 by David Perlin, Ph.D., and Ann Cohen. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.