Sexually Transmitted Diseases (Human)
Primary reference(s)
WHO, no date. Sexually Transmitted Infections (STIs). Fact Sheet. World Health Organization (WHO). Accessed 14 September 2020.
Additional scientific description
Sexually transmitted diseases (STDs) are spread predominantly by sexual contact, including vaginal, anal and oral sex. Some sexually transmitted diseases can also be transmitted through non-sexual means such as via blood or blood products. Many sexually transmitted diseases, including syphilis, hepatitis B, human immunodeficiency virus (HIV), chlamydia, gonorrhoea, herpes, and human papillomavirus (HPV), can also be transmitted from mother to child during pregnancy and childbirth (WHO, no date).
More than 30 different bacteria, viruses and parasites are known to be transmitted through sexual contact. Eight of these pathogens are linked to the greatest incidence of sexually transmitted disease. Of these eight infections, four are currently curable: syphilis, gonorrhoea, chlamydia and trichomoniasis. The other four are viral infections which are incurable: hepatitis B, herpes simplex virus (HSV or herpes), HIV, and HPV. Symptoms or disease due to the incurable viral infections can be reduced or modified through treatment (WHO, no date).
Metrics and numeric limits
Not available.
Key relevant UN convention / multilateral treaty
International Health Regulations (2005), 3rd ed. (WHO, 2016a).
Examples of drivers, outcomes and risk management
More than 1 million sexually transmitted diseases are acquired every day (WHO, no date).
In 2016, it was estimated that there were 376 million new infections attributable to one of four sexually transmitted diseases: chlamydia (127 million), gonorrhoea (87 million), syphilis (6.3 million) and trichomoniasis (156 million) (Rowley et al., 2019).
Sexually transmitted diseases can increase vulnerability to other diseases – for example, herpes and syphilis can increase the risk of HIV acquisition three-fold or more. Furthermore, mother-to-child transmission of sexually transmitted diseases can result in adverse birth outcomes including stillbirth, neonatal death, low-birthweight and prematurity, sepsis, pneumonia, neonatal conjunctivitis, and congenital deformities (WHO, no date).
One important prevention tool against sexually transmitted infections is vaccination. Currently, vaccines are available to protect against infection with HPV, hepatitis A and hepatitis B (WHO, 2016b).
Antimicrobial resistance of sexually transmitted diseases, in particular gonorrhoea, has increased rapidly in recent years, making preventative approaches such as counselling and access to barrier methods an important part of effective risk management for these diseases (WHO, no date).
The World Health Organization is working with countries and partners with regard to sexually transmitted disease prevention and treatment, through the Global Health Sector Strategy on Sexually Transmitted Infections 2016–2021, including the setting of global norms and standards, strengthening surveillance systems (including for antimicrobial resistance) and supporting the delivery of a global research agenda on sexually transmitted diseases (WHO, 2016b).
References
Newman, L., J. Rowley, S. Vander Hoorn, E. Korenromp, N. Low, M. Unemo, L.J. Abu-Raddad, et al. 2019. Global and Regional Estimates of the Prevalence and Incidence of Four Curable Sexually Transmitted Infections in 2016. Accessed 20 September 2020.
WHO, no date. Sexually Transmitted Infections. Fact Sheet. World Health Organization (WHO). Accessed 14 September 2020.
WHO, 2016a. International Health Regulations (2005), 3rd ed. World Health Organization (WHO). Accessed 26 September 2020.
WHO, 2016b. Global Health Sector Strategy on Sexually Transmitted Infections, 2016-2021. World Health Organization (WHO). Accessed 14 September 2020.