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Sexually Transmitted Diseases

Sexually Transmitted Diseases


Promote healthy sexual behaviors, strengthen community capacity, and increase access to quality services to prevent sexually transmitted diseases (STDs) and their complications.


STDs refer to more than 35 infectious organisms that are transmitted primarily through sexual activity. STD prevention is an essential primary care strategy for improving reproductive health.1

Despite their burdens, costs, and complications, and the fact that they are largely preventable, STDs remain a significant public health problem in the United States. This problem is largely unrecognized by the public, policymakers, and health care professionals. STDs cause many harmful, often irreversible, and costly clinical complications, such as:

  • Reproductive health problems
  • Fetal and perinatal health problems
  • Cancer
  • Facilitation of the sexual transmission of HIV infection2

Why Is Sexually Transmitted Disease Prevention Important?

The Centers for Disease Control and Prevention (CDC) estimates that there are approximately 20 million new STD infections each year—almost half of them among young people ages 15 to 24.3 The cost of STDs to the U.S. health care system is estimated to be as much as $16 billion annually.4 Because many cases of STDs go undiagnosed—and some common viral infections, such as human papillomavirus (HPV) and genital herpes, are not reported to CDC at all—the reported cases of chlamydia, gonorrhea, and syphilis represent only a fraction of the true burden of STDs in the United States.

Untreated STDs can lead to serious long-term health consequences, especially for adolescent girls and young women. CDC estimates that undiagnosed and untreated STDs cause at least 24,000 women in the United States each year to become infertile.5

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Understanding Sexually Transmitted Diseases

Several factors contribute to the spread of STDs.

Biological Factors

STDs are acquired during unprotected sex with an infected partner.6 Biological factors that affect the spread and complications of STDs include:

  • Asymptomatic nature of STDs. The majority of STDs either do not produce any symptoms or signs, or they produce symptoms so mild that they are unnoticed; consequently, many infected persons do not know that they need medical care.
  • Gender disparities. Women suffer more frequent and more serious STD complications than men do. Among the most serious STD complications are pelvic inflammatory disease, ectopic pregnancy (pregnancy outside of the uterus), infertility, and chronic pelvic pain.7
  • Age disparities. Young people ages 15 to 24 account for half of all new STDs, although they represent just 25% of the sexually experienced population. Adolescent females may have increased susceptibility to infection because of increased cervical ectopy.8

Social, Economic, and Behavioral Factors

The spread of STDs is directly affected by social, economic, and behavioral factors. Such factors may cause serious obstacles to STD prevention due to their influence on social and sexual networks, access to and provision of care, willingness to seek care, and social norms regarding sex and sexuality. Among certain vulnerable populations, historical experience with segregation and discrimination exacerbates the influence of these factors.

Social, economic, and behavioral factors that affect the spread of STDs include:

  • Racial and ethnic disparities. Certain racial and ethnic groups (mainly African American, Hispanic, and American Indian/Alaska Native populations) have high rates of STDs, compared with rates for whites. Race and ethnicity in the United States are correlated with other determinants of health status, such as poverty, limited access to health care, fewer attempts to get medical treatment, and living in communities with high rates of STDs.9
  • Poverty and marginalization. STDs disproportionately affect disadvantaged people and people in social networks where high-risk sexual behavior is common, and either access to care or health-seeking behavior is compromised.
  • Access to health care. Access to high-quality health care is essential for early detection, treatment, and behavior-change counseling for STDs. Groups with the highest rates of STDs are often the same groups for whom access to or use of health services is most limited.10, 11
  • Substance abuse. Many studies document the association of substance abuse with STDs.12 The introduction of new illicit substances into communities often can alter sexual behavior drastically in high-risk sexual networks, leading to the epidemic spread of STDs.13
  • Sexuality and secrecy. Perhaps the most important social factors contributing to the spread of STDs in the United States are the stigma associated with STDs and the general discomfort of discussing intimate aspects of life, especially those related to sex.14 These social factors separate the United States from industrialized countries with low rates of STDs.
  • Sexual networks. Sexual networks refer to groups of people who can be considered “linked” by sequential or concurrent sexual partners. A person may have only 1 sex partner, but if that partner is a member of a risky sexual network, then the person is at higher risk for STDs than a similar individual from a lower-risk network.

Emerging Issues in Sexually Transmitted Diseases

There are several emerging issues in STD prevention:

  • Each state must address system-level barriers to timely treatment of partners of persons infected with STDs, including the implementation of expedited partner therapy for the treatment of chlamydial and gonorrheal infections. 
  • Enhanced data collection on demographic and behavioral variables, such as the sex of an infected person’s sex partner(s), is essential to understanding the epidemiology of STDs and to guiding prevention efforts.
  • Innovative communication strategies are critical for addressing issues of disparities, facilitating HPV vaccine uptake, and normalizing perceptions of sexual health and STD prevention, particularly as they help reduce health disparities.
  • It is necessary to coordinate STD prevention efforts with the health care delivery system to leverage new developments provided by health reform legislation.


1King K, et al. Sexually Transmitted Diseases. 4th Edition. 2007. The McGraw-Hill Companies: New York.

2St. Louis ME, Wasserheit JN, Gayle HD, editors. Janus considers the HIV pandemic: Harnessing recent advances to enhance AIDS prevention. Am J Public Health. 1997;87:10-12.

3Satterwhite CL, et al. Sexually transmitted infections among U.S. women and men: Prevalence and incidence estimates, 2008. Sex Transm Dis 2013; 40(3): pp. 187-193.

4Owusu-Edusei K, et al. The estimated direct medical cost of selected sexually transmitted infections in the United States, 2008. Sex Transm Dis 2013; 40(3): pp. 197-201.

5Centers for Disease Control and Prevention. Unpublished estimate.

6Institute of Medicine. The hidden epidemic: Confronting sexually transmitted diseases. Eng TR, Butler, WT, editors. Washington: National Academies Press; 1997.

7Chandra A, Stephen EH. Impaired fecundity in the United States: 1982–1995. Fam Plann Perspect. 1998 Jan–Feb;30(1):34-42.

8Centers for Disease Control and Prevention. Sexually Transmitted Disease Surveillance 2014. Atlanta: U.S. Department of Health and Human Services; 2015.

9Krieger N, Waterman PD, Chen JT, et al. Monitoring socioeconomic inequalities in sexually transmitted infections, tuberculosis and violence: Geocoding and choice of area-based socioeconomic measures. Public Health Rep. 2003 May–Jun;118(3):240-60.

10Geisler WM, Chyu L, Kusunoki Y, et al. Health insurance coverage, health-care-seeking behaviors, and genital chlamydia infection prevalence in sexually active young adults. Sex Transm Dis. 2006 Jun;33(6):389-96.

11Institute of Medicine. Unequal treatment: Confronting racial and ethnic disparities in health care. Washington: National Academies Press; 2002.

12Beltrami J, Wright-DeAguero L, Fullilove M, et al. Substance abuse and the spread of sexually transmitted diseases. [Commissioned paper for the IOM Committee on Prevention and Control of STDs]. Washington: Institute of Medicine; 1997.

13Marx R, Aral SO, Rolfs RT, et al. Crack, sex, and STDs. Sex Transm Dis. 1991 Apr–Jun;18(2):92-101. [Review].

14Brandt, A. No magic bullet: A social history of venereal disease in the United States since 1880. New York: Oxford University Press; 1985.

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