Sexually Transmitted Disease Statistics

Sexually transmitted infections (STIs), once called venereal diseases, are among the most common infectious diseases in the United States today. More than 20 STIs have now been identified, and they affect more than 13 million men and women in this country each year. The annual comprehensive cost of STIs in the United States is estimated to be well in excess of $10 billion. Nearly two-thirds of all STIs occur in people younger than 25 years of age. Most of the time, STIs cause no symptoms, particularly in women. When and if symptoms develop, they may be confused with those of other diseases not transmitted through sexual contact. Even when an STI causes no symptoms, however, a person who is infected may be able to pass the disease on to a sex partner.

1. Some STIs can spread into the uterus (womb) and fallopian tubes to cause pelvic inflammatory disease (PID), which in turn is a major cause of both infertility and ectopic (tubal) pregnancy. The latter can be fatal.
   
   
2. STIs in women also may be associated with cervical cancer. One STI, human papillomavirus infection (HPV), causes genital warts and cervical and other genital cancers.
   
   
3. STIs can be passed from a mother to her baby before, during, or immediately after birth; some of these infections of the newborn can be cured easily, but others may cause a baby to be permanently disabled or even die.¹
   
   
4. Genital herpes is the most common sexually transmitted viral infection in the United States, with an estimated 45 million people infected.² In addition, one million people acquire genital herpes infection each year in the United States.³
   
   
5. Human papilloma virus (HPV) is a virus that infects the skin and mucous membranes (tissues that line the mouth, cervix, vagina, urethra and anus) of humans. Of the more than 100 strains of HPV, approximately 30 cause genital infections⁴ HPV is primarily spread by skin-to-skin contact with an infected person or by contact with body fluids contaminated with the virus. Five to six million Americans become infected with genital HPV every year.²
   
   
6. Two million Americans are currently infected with Chlamydia trachomatis, and three million more will acquire the infection this year.² Chlamydia trachomatis is primarily transmitted through sexual activity and is the most common bacterial sexually transmitted infection. It can also be passed from pregnant women to their newborn infants during childbirth.
   
   
7. Gonorrhea is the second most common reportable bacterial sexually transmitted infection in America. About 650,000 Americans become infected with gonorrhea each year² Gonorrhea is spread through sexual contact and sexual intercourse.

1. National Institutes of Health, National Institute of Allergy and Infectious Diseases. An Introduction to Sexually Transmitted Infections. July 1999. www.niaid.nih.gov/factsheets/stdinfo.htm
   
   
2. Fleming DT, McQuillan GM, Johnson RE, et al. Herpes simplex virus type 2 in the United States, 1976 to 1994. N Engl J Med. 1997;337:1105-1111.
   
   
3. American Social Health Association. Sexually Transmitted Diseases in America: How Many Cases and at What Cost? Menlo Park, CA: Kaiser Family Foundation; 1998
   
   
4. Division of STD Prevention. Prevention of genital HPV infection and sequelae: Report of an external consultants’ meeting. Department of Health and Human Services, Atlanta: Centers for Disease Control and Prevention (CDC), December 1999.