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What are STIs?

Sexually transmitted infections (STIs) are caused by:

  • viruses (for example HIV, herpes, hepatitis and warts)
  • bacteria (including gonorrhoea, chlamydia, non-specific urethritis/NSU, syphilis)
  • parasites (such as crabs and scabies).

It’s possible to get crabs and scabies without having sex, as they can be picked up from bedding, towels and clothes.

Questions about STIs

These are some of the questions you may have about STIs. There’s more information about each STI on the pages in this section of the website.

Will ‘safer sex’ protect me from STIs?

Condoms are very good at stopping HIV. However, other STIs are much easier to catch or pass on than HIV, so it’s possible to get one even if you use condoms. But using them does make it less likely.

Fucking without condoms and sucking are the most common ways that STIs are passed on. But they can be spread by other types of sex (such as fisting, fingering, sharing sex toys and rimming).

Will I know if I have an STI, or if the man I’m having sex with has one?

Sometimes you may not notice any symptoms when you or someone else has an STI, or you can have an infection for quite a long time before the symptoms show. The symptoms can be inside someone’s body where they can’t be seen, such as when herpes, warts or a syphilis sore is inside someone’s arse.

Some men go to a clinic to be checked a couple of times a year. If you have sex with lots of men you might want to be checked more often. But if you feel there might be something wrong then a clinic visit is strongly recommended. If you have any symptoms, then tell the clinic – it should get you seen quicker.

What can I do if I get an STI?

The tests for STIs are quick and easy, and most STIs can be cured. Those that can’t be cured (like herpes and HIV) can often be controlled with drugs. There are two STIs – hepatitis A and B – that you can be vaccinated against.

What happens if I don’t get an STI treated?

STIs need to be treated. Even if the symptoms seem to get better, you’ll still have an infection. And until you’re given the all-clear, you could give it to others.

Infections that are left untreated can end up causing serious health problems or damage to your body, such as arthritis or epididymitis (an infection of the balls that can cause you to lose one of them). And if you have an STI, you’re more likely to pick up or pass on HIV if you have unprotected sex. That’s because whether you’re HIV positive or negative, having STIs puts a strain on your immune system, making you more open to other infections or illnesses.

STIs can have worse symptoms and be harder to treat in people with HIV. They also make it easier for HIV to spread. That’s because HIV ‘piggy-backs’ on STIs, helping it to get out of one body into another. STIs can cause inflamed or broken skin that might bleed, or sores or discharges. All of these give HIV more chance to get in or out of our bodies, whether we have HIV or not.

If you have HIV, STIs push up your viral load, meaning more HIV is in your blood, cum and anal mucus. This makes you more likely to pass on HIV and more likely to get ill.

How common are STIs?

Infections are getting more common whether you are gay, bisexual or straight. Your chances of getting one can depend on:

  • how many people you have sex with
  • what type of sex you have
  • whether you use condoms or not.

Men with more sexual partners are much more likely to report an infection.

Last review: 25/09/2014
Next review: 31/09/2017