About STIs and HIV

What do STIs have to do with HIV transmission?

Addressing sexually transmitted infections (STIs) is a crucial component to preventing the spread of HIV. HIV is one type of STI, but an STI like syphilis, herpes, gonorrhea, chlamydia, or HPV can increase both an HIV-negative person’s risk of becoming infected with HIV and an HIV-positive person’s risk of transmitting HIV to someone else.

Research suggests that HIV-negative individuals with an STI may be at increased risk of becoming infected with HIV through anal sex, vaginal sex, frontal sex (a term used by some trans people to refer to sex using genitals on the front of the body) and oral sex. Research also suggests that HIV-positive individuals with an STI may be at increased risk of passing HIV to someone else through anal, vaginal and frontal sex.

STIs can cause swelling, redness, and pain in the infected area. However, many people who have an STI have no symptoms at all—this is known as being asymptomatic—so neither they nor their partner may realize they are infected. Getting tested is the only way to know if you have an STI.

All types of STIs cause inflammation and therefore may increase the risk of becoming infected with HIV in this way. Also, some types of STIs increase the risk of HIV infection through ulcers, which create “holes” or ways for HIV to enter the body through the mouth, genitals or rectum.

Inflammation increases the concentration of “activated” immune cells in the area infected with the STI. Although the inflammatory response is meant to help fight the sexually transmitted infection, HIV likes to infect some of these recruited immune cells, also known as CD4 cells. Also, HIV finds it easier to infect, and replicate in, CD4 cells that are “activated”. Therefore, if someone has an STI in the mouth, genitals or rectum, and that area is exposed to HIV, the higher concentration of “activated” CD4 cells facilitates HIV infection, replication and spread throughout the body.

If a person living with HIV has an STI, then inflammation will “activate” and recruit more immune cells to the infected genitals or rectum. Some of the immune cells in a person living with HIV are already infected with HIV, therefore the inflammatory response brings more HIV (contained in the infected immune cells) to the site of the STI in the genitals or rectum. Consequently, more HIV enters the body fluids in that area. For example, a vaginal STI increases the amount of the virus (viral load) in the vaginal fluid. Research shows that the more virus there is in the body fluids of a person living with HIV the higher the risk of passing HIV to someone else. HIV also replicates, or makes more HIV, quicker in immune cells that have been “activated” through inflammation, compared to immune cells that are not “activated.”

What trends do we see of STI’s in California and Sonoma County?

In 2017, the burden of notifiable bacterial STDs in California (chlamydia, gonorrhea, and syphilis) continued to be substantial and increasing when compared against 2016 and the prior five years. San Francisco County is seeing even higher spikes, where people are contracting chlamydia at nearly twice the rate of the rest of California. Gonorrhea among women is up 47 percent, and there’s a concerning spike in the number of babies being born with congenital syphilis. Important disparities persist, with the highest rates found among young people, African Americans, and gay, bisexual and other men who have sex with men (MSM). These populations are at higher risk for related serious health outcomes such as HIV infection, infertility, ocular and neurosyphilis, and multi-drug resistant gonorrhea. Exposure to syphilis in pregnancy can lead to stillbirth and deformities from congenital syphilis.

There’s also an overlap between syphilis and methamphetamine, as using the drug can increase the odds of having unprotected sex and transmitting the disease, according to a recent report from the U.S. Centers for Disease Control and Prevention. For example, women who don’t have safe places to live, or who have substance use issues, can find themselves using sex to provide them with a safe place to stay.

Sonoma County is experiencing a spike in syphilis cases, with the number of syphilis cases increasing 460 percent between 2013 and 2018. About 43 percent of residents with early-stage syphilis in 2018 were experiencing homelessness, and 51 percent were using methamphetamine. In 2017, only 12 percent reported being homeless, while 28 percent said they had used meth. It’s difficult to calculate the prevalence of STDs in homeless versus housed populations, but officials say people living on the street are at heightened risk.

What does Face to Face do about STIs?

Face to Face works closely with the Sonoma County Department of Health and our clinical partners to identify people in need of testing and treatment, and linking people to care. Anyone who comes to our offices to access our services can also be linked to STI testing and treatment, and we’ll support you along the way. Face to Face also helps lead outreach to homeless encampments to provide STI and HIV testing, syringe exchange, toiletry, and other hygiene kits, and linking people to care for treatment.

Where can I get tested for STIs?

Planned Parenthood: 1140 Sonoma Ave. Bldg.3, Santa Rosa (707) 527-7656

Santa Rosa Community Health: 751 Lombardi Court, Santa Rosa (707) 547-2222

Russian River Health Center: 16319 3rd Street, Guerneville (707) 869-2849

Russian River Teen Clinic: 625 Petaluma Avenue, Sebastopol  (707) 887-0427

For further reading:


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