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Know Your Chances

It is common to have questions or feel concerned about sexually transmitted infections (STIs). The chances of getting or passing an STI to partners can depend on a few things:    

1)  Do you or your partner(s) have an STI?

Many STIs do not show symptoms, and people can have an STI without knowing it. Getting tested is the only way to know if you have an STI. How someone looks, the partners they have, and other assumptions about a person’s lifestyle are not good ways to tell if someone has an STI. Your partner(s) would have to have an STI to be able to pass it to you.

2)  Are you using any safer sex methods, such as condoms, vaccines or medication?

3)  What kind of sex are you having?

STIs are passed in different ways, so your chances of getting some STIs can change for different sexual activities.

If you want to learn more about  STIs and how they are passed, you can find more in our STIs at a Glance chart.

My Chances

Important factors that affect your chances of getting an STI:

  • The actual chances of an STI being passed are unique to each infection.  Some STIs are more common than others.  You are less likely to get an infection that is not very common, even if the infection can be passed that way.
  • Sometimes condoms can break or slip. If this happens, the chances of getting an STI are the same if no condom was used. Condoms are not as good at preventing infections passed by skin-to-skin contact such as syphilis, herpes and HPV.
  • Body fluids like blood, semen/cum, vaginal fluid, rectal fluid and breastmilk can pass STIs. This will depend on the infection and the type of contact you may have with your sexual partner. Fluids like sweat, tears, saliva and urine do not pass STIs.
  • People living with HIV can take medication to lower the amount of virus in their blood to a very low level. This is called undetectable viral load, and it means that HIV cannot be passed to others through sexual activities (also called Undetectable = Untransmissible, or U=U).
  • Pre-exposure prophylaxis (PrEP) is medication that you can take daily, or as prescribed to lower your chances of getting HIV.

Can the infection be passed to you if your partner has it?

The charts below can give you an idea of which sexual activities are more or less likely to pass an infection to you if your partner has that infection.

The table is based on published research and reviewed by STI experts in British Columbia. It does not cover every situation or STI. 

What the chart mean:

Not passed: This infection cannot be passed between people by this kind of sex.

Not commonly passed: This is not a common way to pass the infection, and would only be possible under the right conditions.

Can be passed:  This type of sex can pass the infection under the right conditions.

Easily passed: The infection is commonly passed between people by this kind of sex.

How to lower your chances of getting an STI

  • Get tested: If you and your partner(s) are testing regularly, you can find out if you have an STI. Be aware of the window period, which is the time it takes for an infection to show up on a test. If you test too early, your results may not be accurate. You can use the Clinic Finder to find services near you in British Columbia.
  • Be informed: There are many ways to have sex that feel great. Choose activities that work for you, and be aware of how different STIs are passed.
  • Safer sex: There are many ways to make sex safer such as using condoms, lube, or planning ahead if you’re using drugs or alcohol. Safer sex can still be great sex!
  • Talk to your partners: Talking to partners about safer sex before you get started can make things easier for everyone. We’ve included some tips on how to start this conversation.

If you or your partner(s) is living with an STI

If you or your partners are being treated for an STI, wait until you have both finished the medication and follow the advice of your health care provider about when you can have genital, oral, or anal sex.

For infections that can be managed, but not treated, such as HIV or herpes, there are medications that can lower your chances of passing on the infection.

There are ways to keep you and your partner(s) healthy, while having an enjoyable sex life.

Still have questions?

If you still have questions about your personal situation or risk, you can:

  • Get more information. We have more information and links below, as well as other resources on this website. You can also search our Answered Questions Library to public questions answered by our sexual health nurses.
  • Ask a question. You can use Options for Sexual Health’s Sex Sense service to have your specific questions answered over the phone or email. Sex Sense cannot be used to diagnose or provide medical care.
  • Talk to a health care provider. Use the clinic finder to locate services, or use HealthLink BC’s 8-1-1 service to discuss your concerns if you don’t have a regular or trusted health care provider.