The Link Between HIV and STDs

How STDs Facilitate HIV Infection and Vice Versa

It is generally accepted that having a sexually transmitted disease (STD) increases a person's risk of getting HIV, both for biological and behavioral reasons.

According to research, STDs like syphilis and gonorrhea cause physical changes that make the HIV virus have easier access to vulnerable cells and tissues of the body, STD co-infection also increases the infectivity of the person with HIV—making them more likely to transmit the virus to others.

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STDs can increase HIV susceptibility in a number of ways:

  • Some STDs cause open wounds or ulcers to form in the genital area. For example, syphilis frequently presents with ulcerative chancres. These wounds, sometimes seen and sometimes not, provide HIV a direct route into the bloodstream.
  • The presence of some STDs can cause the body to increase the concentration of CD4 T-cells in the genital area. It has been well established that increased concentrations of these cells can provide HIV with a vulnerable target for infection.
  • People infected with an STD also have increased concentrations of HIV in their seminal and vaginal fluids, increasing the possibility of HIV transmission.

Prime among the concerns are STDs like infective syphilis, gonorrhea, and herpes (HSV), with evidence that chlamydia can also increase HIV risk in women.

STD Statistics in the U.S.

According to the Centers for Disease Control and Prevention (CDC), nearly 20 million new STD infections occur every year, accounting for almost $16 billion in healthcare costs.

Three diseases make up the bulk of the infections:

  • Chlamydia: 1,800,000 infections at a rate of 552.8 per 100,000
  • Gonorrhea: 616,392 infections at a rate of approximately 200 per 100,000
  • Syphilis (primary and secondary): 129,813 infections at a rate of 30 per 100,000

Anyone who is sexually active could be at risk of becoming infected with an STD.

The rate of STD infections is particularly high among gay and bisexual men, who also account for the highest rate of HIV infections in the U.S. Gay and bisexual men account for almost all primary and secondary syphilis cases.

To this end, If you are a sexually active gay or bisexual man, you should be tested for syphilis, chlamydia, gonorrhea, and HIV at least once a year. More frequent STD testing, between every three to six months, is recommended for gay or bisexual men at high risk, especially those who have multiple sex partners, use recreational drugs, or practice condomless sex. 

Benefits of STD Screening and Treatment

Many sexually transmitted infections do not cause symptoms in the early stages, so you can get it or give it to your partner without realizing it.

If you have an STD diagnosis, you should receive treatment as soon as possible—to both treat the infection and potentially decrease the risk of HIV transmission.

According to the latest research, HIV-positive people on STD therapy tend to shed far less HIV and to shed the virus less frequently than those not on treatment. Shedding is the state where HIV is present in semen, vaginal secretions, blood, or breast milk even when a person has an undetectable HIV viral load.

Additionally, safer sex counseling can help a person uninfected with HIV or another STD to identify their personal risk factors and find ways to better reduce their risk of these infections.

A Word From Verywell

Even if a person is on the HIV prevention pill (PrEP) or is taking full-time antiretroviral therapy, STDs can increase the risk of HIV transmission, putting yourself or others at risk.

It is, therefore, important to remember the following take-home points:

  • You have a greater chance of HIV if you have an STD.
  • Having an STD and HIV can increase your risk of spreading HIV.
  • STD treatment may help slow the spread of HIV.
  • HIV therapy does not prevent you from getting another type of STD.
  • Condoms are still the single best way to reduce your risk of getting an STD, including HIV.
6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Peterman, T.; Newman, D.; Maddox, L; et al. Risk for HIV following a diagnosis of syphilis, gonorrhea or chlamydia: 328,456 women in Florida, 2000–2011.International Journal of STD and AIDS. 2015:26(2):113-19. doi:10.1177/0956462414531243.

  2. Centers for Disease Control and Prevention. STDs and HIV.

  3. Center for Disease Control and Prevention. CDC Fact Sheet: Reported STDs in the United States. 2013. Print.

  4. Centers for Disease Control and Prevention. Chlamydia.

  5. Centers for Disease Control and Prevention. Gonorrhea.

  6. Centers for Disease Control and Prevention. Syphilis.

Additional Reading

By Mark Cichocki, RN
Mark Cichocki, RN, is an HIV/AIDS nurse educator at the University of Michigan Health System for more than 20 years.