Two sexually transmitted infections have widely available, highly effective vaccines right now: HPV (human papillomavirus) and hepatitis B. A third, hepatitis A, is vaccine-preventable and can spread through sexual contact. Beyond those, a meningitis vaccine has shown unexpected cross-protection against gonorrhea, and the mpox vaccine is recommended for people at higher risk of sexual exposure. Here’s what each vaccine does, who should get it, and what’s still in the pipeline for other STIs.
HPV: The Most Impactful STI Vaccine
The current HPV vaccine (Gardasil 9) protects against nine strains of human papillomavirus: types 6, 11, 16, 18, 31, 33, 45, 52, and 58. Types 16 and 18 alone cause about 66% of cervical cancers in the United States, and the five additional cancer-causing strains account for roughly another 15%. That means the vaccine covers the strains responsible for about 81% of cervical cancers. It also protects against types 6 and 11, which cause most genital warts, with 99% efficacy in clinical trials.
HPV vaccination is routinely recommended starting at age 11 or 12, though it can be given as early as 9. If you start the series before age 15, you only need two doses. Starting at 15 or older requires three doses. The vaccine is approved for people through age 45, though the greatest benefit comes from getting vaccinated before any sexual exposure to the virus. Beyond cervical cancer, HPV vaccination also helps prevent cancers of the throat, anus, penis, vagina, and vulva.
Hepatitis B: Long-Term Liver Protection
Hepatitis B spreads through blood, semen, and other body fluids, making sexual contact one of the most common routes of transmission. The vaccine is given as either a two-dose or three-dose series depending on the brand. The three-dose series is spread over six months, while the two-dose version is completed about a month apart. Completing the full series is essential for protection, and once you do, the vaccine provides long-term defense against both acute infection and the chronic form of hepatitis B that can lead to liver damage, cirrhosis, and liver cancer.
Most people born in the U.S. after 1991 received this vaccine as infants. If you weren’t vaccinated as a child, the CDC recommends it for all adults through age 59, and for anyone 60 or older with risk factors like multiple sexual partners, a partner who has hepatitis B, or a recent STI diagnosis.
Hepatitis A: Sexually Transmitted but Preventable
Hepatitis A isn’t always grouped with STIs, but it absolutely spreads through sexual activity. Transmission can occur from any sexual contact with an infected person, not just oral-anal contact. The CDC specifically recommends hepatitis A vaccination for men who have sex with men, people who inject drugs, and anyone living with or having sex with a person who has the virus. Outbreaks linked to sexual transmission have been well documented, and the vaccine is safe, effective, and widely available.
Mpox: Vaccination for Higher-Risk Groups
Mpox (formerly monkeypox) can spread through close skin-to-skin contact during sex. The Jynneos vaccine is a two-dose series recommended for people at elevated risk. The CDC’s eligibility criteria focus heavily on sexual risk factors: gay, bisexual, and other men who have sex with men, as well as transgender and nonbinary individuals who in the past six months have had a new STI diagnosis, more than one sexual partner, or sex at a commercial venue like a bathhouse. It’s also recommended for anyone with known or suspected exposure to a person with mpox, or for travelers to areas with active outbreaks who anticipate sexual contact with new partners.
Gonorrhea: An Unexpected Breakthrough
No vaccine was designed to prevent gonorrhea, but one appears to work anyway. A meningitis B vaccine originally developed to protect against bacterial meningitis has shown cross-protection against gonorrhea, because the bacteria that cause these two infections are closely related. A 2024 study published in The Journal of Infectious Diseases found that two doses of the vaccine reduced gonorrhea risk by 33 to 40%, and even a single dose provided about 26% protection.
That level of protection is moderate, but gonorrhea is becoming increasingly resistant to antibiotics, which makes even partial prevention valuable. In 2025, the UK became the first country to formally roll out the meningitis B vaccine as a tool against gonorrhea. Other countries are watching the data closely.
Insurance Coverage for STI Vaccines
Under the Affordable Care Act, most private health insurance plans are required to cover vaccines recommended by the Advisory Committee on Immunization Practices (ACIP) with no cost sharing. That includes the HPV, hepatitis B, and hepatitis A vaccines. You should pay nothing out of pocket if you have a non-grandfathered health plan, which covers the vast majority of people with employer-sponsored or marketplace insurance. Medicaid expansion plans in participating states also cover these vaccines without cost sharing.
STIs That Still Lack a Vaccine
Several of the most common STIs still have no approved vaccine, though research is underway for some of them.
Herpes (HSV-2): A genital herpes vaccine has been a goal for decades, but the virus is difficult to target because it hides in nerve cells and reactivates unpredictably. GSK has a therapeutic vaccine in phase 1/2 trials, and Moderna has a prophylactic candidate in phase 1 testing. Neither is close to market approval.
HIV: Despite enormous investment, no HIV vaccine has succeeded in large-scale trials. The virus mutates so rapidly and attacks the immune system so directly that traditional vaccine approaches have failed. Prevention currently relies on condoms and pre-exposure prophylaxis (PrEP) rather than vaccination.
Syphilis: Syphilis rates are surging globally, and a vaccine would be transformative, especially for preventing congenital syphilis in newborns. The bacterium that causes syphilis has an unusually sparse outer surface with very few proteins for a vaccine to target, earning it the nickname “stealth pathogen.” A proof-of-concept vaccine was demonstrated in 1973, showing that protection is biologically possible, but the vaccine would need to work across many circulating strains, be safe for pregnant women, and remain effective in people with HIV. No candidate is currently in human trials.
Chlamydia: The most commonly reported bacterial STI in the world still has no vaccine, though an mRNA chlamydia vaccine recently entered phase 1/2 trials in adults aged 18 to 29. Results are not yet available.