How Does STD Infection Increase HIV Risk?

Numerous STDs are not only dangerous in and of themselves. Many STDs can also increase the risk of becoming infected with other STDs, including HIV. HIV-positive individuals with STDs are also more infectious. They are three to five times more likely than individuals without STDs to transmit HIV during sexual activity.

A patient sitting alone in a doctor's office
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How Do STDs Increase HIV Risk?

STDs increase a person's risk of acquiring HIV in one of two ways.

  1. They can cause lesions on the skin, making it easier for HIV to enter the body. Some STDs that increase HIV risk in this way include:
  2. Syphilis -- which causes painless chancre sores on the skin or in the mouth
  3. Chancroid -- which can lead to painful ulcers in the genital region
  4. Herpes -- which causes groups of blisters to form near the mouth or genitals
  5. They can cause inflammation. Inflammation is triggered by the immune system. Where there is inflammation, more immune cells are recruited. Since HIV prefers to infect immune cells, any disease that causes an increase in these cells also will make it easier for a person to become infected with HIV. STDs that increase HIV risk in this way include:
  6. Gonorrhea
  7. Chlamydia
  8. Trichomoniasis

Of course, many STDs increase a person's susceptibility to HIV in both ways. It is therefore extremely important for anyone who has an STD to be treated. It can help to protect their long-term health. As can, unsurprisingly, practicing safer sex. Reliably, and properly, using condoms for all sexual activity will greatly reduce an individual's risk of acquiring HIV.

Regular Screening Is Essential

It is extremely important for individuals with STDs to be treated. However, before a person can be treated, they first need to be diagnosed. For that, regular screening is essential. Most sexually transmitted diseases are asymptomatic. That means they have no symptoms, and people may not realize they're infected. With no symptoms, the only way to ensure a timely STD diagnosis is screening. Otherwise, an infection can linger under the radar for many years. That is why it's not enough just to go for STD testing when you have symptoms. Every sexually active adult should consider being screened for STDs on a regular basis. This not only reduces HIV risk, but it also lowers the risk of STD-related infertility, a problem that does not only affect women.

Examining Overlapping Biological and Behavioral Risk

It's worth noting that people who have one STD tend to be at risk for other STDs for behavioral and social reasons. If someone has gotten an STD, there's a good chance that they are having unprotected sex. That's the biggest risk factor for getting an STD. There is also a reasonable chance that they may be part of a community or sexual network that has a higher than average prevalence of STDs. Unfortunately, that last factor is a big one in STD risk. Individuals often meet sexual partners within their own social network or community. If that community has a lot of STDs, their risk of acquiring one is substantially higher than for someone having sex in a low-risk community. That's why community-level prevention and treatment is so important. The hidden epidemic is bigger than individual sexual health.

Behavioral risk factors for acquiring an STD include:

  • Having unprotected sex, outside of a committed relationship where both partners have been tested for STDs. Unprotected sex includes vaginal, oral, and anal sex without a condom or other barrier
  • Having multiple, concurrent sex partners
  • Having anonymous sex, for example in bathrooms or after meeting on a hookup app.
  • Having sex when under the influence of alcohol or drugs, which can make you less likely to negotiate safe sex or make intentional decisions about sexual encounters.
  • Being part of a community with a higher than average prevalence of STDs, such as being an African American man who has sex with men. 

Options for Reducing HIV Risk 

There are several ways that you can reduce your risk of acquiring HIV. The most important one is to consistently practice safer sex. HIV does not spread through casual contact. If you always use barriers for sex, your risk of acquiring HIV will be very low. If you are at elevated risk of HIV, you may also want to consider pre-exposure prophylaxis or PrEP. People at high risk of HIV can take the anti-HIV medication in order to reduce their risk of becoming infected. Finally, it's important to get tested regularly and encourage your partners to do the same. People are at the greatest risk of transmitting HIV in the time before they know they have it. 

2 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. Pines HA, Wertheim JO, Liu L, Garfein RS, Little SJ, Karris MY. Concurrency and HIV transmission network characteristics among MSM with recent HIV infection. AIDS. 2016 Nov 28;30(18):2875-2883.

  2. Klein H. Anonymous sex and HIV risk practices among men using the Internet specifically to find male partners for unprotected sex. Public Health. 2012 Jun;126(6):471-81. doi: 10.1016/j.puhe.2012.01.023

Additional Reading

By Elizabeth Boskey, PhD
Elizabeth Boskey, PhD, MPH, CHES, is a social worker, adjunct lecturer, and expert writer in the field of sexually transmitted diseases.