What are Sexually Transmitted Infections?

Sexually transmitted infections, also called STIs (sometimes called STDs)  are infections that can pass through sexual activity; some pass through the exchange of body fluids (blood, genital fluids, anal fluid) some can pass through intimate skin to skin contact; some can pass through pregnant person to child during pregnancy, birth, breast/chest feeding; with sexual activities using safer sex barriers like condoms, greatly reduces the chances of most STIs.

How are STIs passed?

In order for an STI to be passed from person to person, one of those people would have to have an STI. Sexual activities carry different risks or chances of an STI passing; they pass through the exchange of blood and/or bodily fluids through sexual activity or sharing drug paraphernalia (needles, inhalation straws); from pregnant person to child during pregnancy and birth.


Teen Health Source: Spreading STIs

Types of STIs

There are several different categories of STIs which include: bacterial; viral; parasitic (not always sexually related but can be).

Want more details about specific types of STIs? Please visit the BC Center for Disease Control for up-to-date and detailed information on the following STIs.

How do I know if I or someone else has an STI?

  • The only way to know is through testing; some people may have symptoms but most often people don’t have symptoms and the only way to know for sure is through testing; we can’t always “tell” by looking at someone if they have an STI.

Who can get STIs

  • Anyone who is sexually active can get an STI. Other ways to transmit STI are through sharing needles/drug equipment, unsterilized tattoo/piercing equipment, needle stick injury, blood or blood product transfusions with contaminated blood (safety measures are applied in Canada since late 1980s and early 1990s); some people may be more at risk for STIs for example if they have a compromised immune system, such as having HIV or if you have an STI and come into contact with another STI, there may be a higher chance of contracting it.

Stigma with STIs

  • Although STIs are common there is still a lot of shame and stigma which can make it difficult sometimes for people to get tested and treated.


Options for Sexual Health has a website dedicated specifically to women* with or at risk of HIV and Hepatitis C? Visit hivhcvoptions.ca for more information and resources.

*Inclusive of Transgender, Two-Spirit, gender diverse people, and cis women.

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