3 STIs you can catch even if you use a condom

Yes. Condoms are one of the best ways to protect yourself from STIs, but they cannot stop every infection.

Condoms work best against infections that spread through body fluids, such as semen, vaginal fluid and blood. This includes HIV, Chlamydia and Gonorrhoea. The World Health Organization (WHO) says that condoms, used correctly and consistently, greatly reduce the risk of most STIs.

They give less protection against infections that spread through skin-to-skin contact, because a condom does not cover all of the skin around the genitals. Three STIs that can get past a condom are:

• Herpes
• human papillomavirus (HPV), which can cause genital warts
• Molluscum contagiosum

All three can spread from skin on the genitals, pubic area, thighs or bottom that a condom does not cover. That is why a condom lowers your risk but cannot remove it completely, and why regular testing is still important.

Condoms work by stopping body fluids, such as semen, vaginal fluid and blood, from passing between partners. This is why they are so good at lowering the risk of pregnancy and of STIs that spread through these fluids.

The evidence is strong. Studies of heterosexual couples where one partner has HIV found that, when condoms were used every time, the other partner was 71% to 80% less likely to get HIV than in couples who did not use condoms. Research has also found that people who use condoms every time are less likely to get Chlamydia and Gonorrhoea than people who use them only some of the time.

Vaginal and anal sex

Most condoms are worn on the penis during vaginal or anal sex. Using a condom during anal sex is especially important. Anal sex carries a much higher risk of HIV than vaginal sex, especially for the receptive partner, the person being penetrated. Read more in our post “Is unprotected anal sex dangerous?”

Oral sex

Some people also use condoms or dental dams during oral sex. The risk of getting HIV through oral sex is much lower than through vaginal or anal sex, but this may not be true for other STIs. Chlamydia, Gonorrhoea, Herpes, Syphilis and HPV can all be passed on through oral sex. A condom on the penis, or a dental dam over the vagina or anus, makes oral sex safer. Our guide “What is an oral sexually transmitted infection?” explains more.

Sharing sex toys

When sex toys are shared, infected body fluids can stay on the surface of the toy. If a toy is not washed between users, infections can pass from one person to the next. Covering a shared toy with a new condom for each person, and washing it after use, lowers the risk. Find out how long an STI can stay on a sex toy.

Other barrier methods

Condoms are not the only barrier method. Internal condoms, which are worn inside the vagina, help protect against STIs during vaginal sex. Dental dams, thin squares of latex or polyurethane, can be used during oral sex on the vagina or anus.

Whether you have vaginal, anal or oral sex, using a condom or another barrier method every time is one of the best ways to protect your sexual health.

Condoms protect the skin they cover. Infections that spread through skin-to-skin contact can pass from areas a condom does not cover, such as the base of the penis, the scrotum, the vulva, the pubic area, the inner thighs and the bottom. Here are three STIs that can get past a condom.

1. Herpes

Herpes is caused by the Herpes simplex virus (HSV). There are two types. HSV-1 is the usual cause of cold sores around the mouth, and HSV-2 more often causes sores on or around the genitals or anus. Both types can infect the genitals, and HSV-1, which is often passed on through oral sex, is now the most common cause of genital Herpes in the UK.

Herpes spreads through skin-to-skin contact with an infected area. A condom lowers the risk, but Herpes can still be passed on if the condom does not cover the infected skin. The virus can also be passed on when there are no symptoms, although it is most contagious from the first tingle or itch until any sores have fully healed.

If you have Herpes, avoid sex, including oral sex, until an outbreak has completely cleared. Antiviral treatment can help with outbreaks, and taking it every day can lower the chance of passing the virus on. Our doctors can advise you on your options. Read more in our post “Do condoms protect against Herpes?”

2. Human papillomavirus (HPV) and genital warts

HPV is a very common group of viruses, with more than 100 different types. Some types cause genital warts, and some high-risk types can lead to cancers, including cancer of the cervix.

HPV spreads through skin-to-skin contact of the genital area, vaginal, anal and oral sex, and sharing sex toys. Condoms lower the risk, but they do not cover all the skin around the genitals, so HPV can still be passed on. Find out whether HPV can be passed on by kissing.

Most people with HPV never have symptoms, and the body usually clears the virus within 2 years. Genital warts sometimes go away on their own within 6 months. Treatments, such as creams or freezing, can remove them, although they can come back.

The HPV vaccine helps protect against genital warts and cancers caused by HPV. In the UK, it is offered to children aged 12 to 13, and some older people can also have it.

3. Molluscum contagiosum

Molluscum contagiosum is a common skin infection caused by a virus. It causes small, raised spots about 2 to 5mm wide, often with a dimple in the middle.

It spreads through direct skin-to-skin contact. It is more common in children, but anyone can get it. In adults it can be passed on through sexual contact, and the spots may then appear around the lower tummy, genitals and thighs. Condoms may lower the risk, but they do not cover all of these areas.

Molluscum contagiosum is usually harmless, and the spots should clear up on their own within 18 months without treatment.

Other infections a condom may not stop

Syphilis is passed on through direct contact with a Syphilis sore, and sores can appear on skin a condom does not cover. Pubic lice spread through close body contact, and condoms do not protect against them.

Condoms still give strong protection, so keep using them. These steps lower your risk even further:

• Use a condom every time you have sex, and put it on before there is any genital contact.
• Use a condom or dental dam for oral sex.
• Avoid sex, including oral sex, if you or your partner has sores, blisters, warts or unusual spots on or around the genitals or mouth.
• Cover shared sex toys with a new condom for each person, and wash them after use.
• Have the HPV vaccine if you are eligible.
• Get tested regularly, and before you stop using condoms with a new partner.

Which test do you need?

If you have a sore, blister, bump or rash on or around your genitals, the Better2Know Blemish Screen can find out what is causing it. A swab from the blemish is tested for Herpes 1, Herpes 2, HPV and Syphilis, with results in 5 days. You can book it at one of our clinics, or order the Blemish Screen home test kit, which uses a swab taken from outside the body.

If you do not have symptoms but are worried about an STI after sex with a new partner, the Full Screen tests for 7 infections: Chlamydia, Gonorrhoea, Hepatitis B, HIV, Mycoplasma, Syphilis and Ureaplasma. You can take it from 28 days after sex, with results in 3 days at a clinic, or order a Full Screen home test kit. Not sure which test is right for you? Read “Which STI test do I need?”

Can you get Herpes if you use a condom?

Yes. A condom lowers the risk of Herpes, but the virus can still pass from skin the condom does not cover, such as the base of the penis, the vulva or the inner thighs. Herpes can also be passed on when there are no symptoms. Using condoms every time and avoiding sex during an outbreak give the best protection.

Can you get HPV if you use a condom?

Yes. HPV spreads through skin-to-skin contact, so it can pass from areas a condom does not cover. Condoms still lower the risk, and the HPV vaccine helps protect against genital warts and cancers caused by HPV.

Do condoms protect against Chlamydia and Gonorrhoea?

Yes. Chlamydia and Gonorrhoea spread mainly through body fluids, and using a condom every time you have sex lowers the risk of catching them. No method is 100% effective, so regular testing is still a good idea if you have a new partner or more than one partner.

Do condoms protect against pubic lice?

No. Pubic lice spread through close body contact, usually during sex, and condoms do not stop them. Read more in our post “Are pubic lice an STI?”

Condoms are one of the best ways to protect yourself from STIs, and you should keep using them. But they cannot cover every area of skin, so Herpes, HPV and Molluscum contagiosum can still be passed on, even when you use a condom correctly.

If you notice a sore, blister, bump or rash, or you are worried after sex with a new partner, get tested. Book a Blemish Screen at a clinic near you or order a home test kit. Prefer to talk it through first? Our Patient Care Team is available 24/7 on 020 7099 0955.

Not in the UK? Choose your country from the selector at the top of the page for local tests and prices.

This article originally appeared on 20 September 2021 and was last updated on 29 September 2026.

Medical review. This article was medically reviewed by Dr Steve Chapman, Doctor with a wealth of clinical experience in the field of STIs, on 6 November 2024. It is general information and not a substitute for personal medical advice.

Sources

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