Sexually Transmitted Infections

An STI is an infection passed between people through sexual contact. STI has replaced the term STD (sexually transmitted disease). Infection is the term used when a bacteria, virus, parasite or other microbe enters the body and multiplies. The term disease is used when there are signs and symptoms of illness. There are many people with STIs who have no symptoms. For this reason, STI is a more accurate term.

The rates of STI in Alberta are still high. For example, the rates of chlamydia are highest in 15 to 24-year-olds.

Here’s what your child needs to know about STIs:

  • STIs are infections that are passed through sexual contact. This includes vaginal, anal, or oral sex or genital skin-to-skin contact.
  • Any type of sexual contact or activity involves some risk.
  • Abstinence—no sexual contact, including vaginal, anal, or oral sex as well as genital skin-to-skin contact—is the only 100% way to prevent an STI.
  • Practicing safer sex lowers the chance of getting an STI.
  • Many STIs have no symptoms, so people may not know they have them.
  • Getting tested is an important way to protect their health and their partner’s health.
  • All STIs can be treated, and most can be cured. Getting treated helps prevent the infection from being passed to someone else.
  • Without treatment, STIs can damage reproductive organs. This could make it harder to become pregnant in the future.
  • Without treatment, STIs can be passed from a pregnant person to their baby before or during delivery.
  • Talking about STIs with partners and practicing safer sex is part of healthy sexual relationships and consent.


Getting tested is important because most STIs don’t have symptoms, are treatable, and don’t go away on their own.

It’s recommended that people who are sexually active get tested for STIs at least once a year. Guidelines for STI testing also recommend other times when it’s a good idea to get an STI test:

  • With new sexual partner(s), before having sex.
  • If there’s bumps, discharge, rashes, or other symptoms.
  • If someone has more than one sexual partner.
  • If someone’s sexual partner has an STI and they didn’t use a condom or other prevention methods, or if the condom broke or slipped off.
  • If someone had sex without a condom and their sexual partner doesn’t know if they have an STI (because they haven’t been tested in a long time).

Learn more below about the different STIs, how they’re passed between people, and how they’re treated.



Chlamydia is caused by bacteria. Most people don’t have symptoms, but some people may have discharge or pain while peeing or during sex. Chlamydia is treated with antibiotics. To learn more, see Chlamydia.

Genital Herpes

Genital herpes is caused by the herpes simplex virus (HSV). It may cause flare-ups of blisters in the genitals, rectum or mouth. Genital herpes can’t be cured. However, there is medicine that can help control it so that the flare-ups don’t happen as often and aren’t as painful. To learn more, see Herpes.

Human Papilloma Virus (HPV)

HPV is a virus with different strains. Some strains can cause skin growths or warts on or around the genitals or anus. The appearance and number of warts can vary greatly. The warts may continue to grow and spread, or they could go away on their own. They can be removed and treated by a health care provider. Other strains of HPV can cause cervical and other types of cancers. Many strains of HPV can be prevented by getting immunized. To learn more, see HPV.


Gonorrhea is caused by bacteria. Most people don’t have symptoms. If there are symptoms, they may include discharge from the penis, vagina or anus. The infection may also cause pain during sex or in the lower abdomen. Gonorrhea can also infect the throat, anus, pelvic organs and eyes. Gonorrhea is treated with antibiotics. To learn more, see Gonorrhea.

Hepatitis B

Hepatitis B is a virus that causes a liver infection. The virus can be passed through sexual contact, sharing needles, or to a baby during birth and delivery. Some people with hepatitis B have no symptoms, while others may be very tired, have a mild fever, or muscle aches. Hepatitis B can be prevented by getting immunized. To learn more, see Hepatitis B.


Syphilis is caused by bacteria. Most people don’t have symptoms. If there are symptoms, they will show up about 21 days after getting infected. Early symptoms may include a painless sore in the genitals, mouth, or rectum or a rash on the palms of the hands, soles of the feet or the whole body. Symptoms will often go away, but the infection remains until it’s treated. Syphilis is treated with antibiotics. To learn more, see Syphilis.


Trichomoniasis (also called ‘trich’) is caused by a parasite. Not everyone has symptoms. The symptoms can include pain when urinating (peeing), or a discharge from the penis or vagina. It can also cause itching in the penis or vagina and pain during sex. Trichomoniasis is treated with antibiotics. To learn more, see Trichomoniasis.


HIV is a virus. It can be passed between people through sexual contact, sharing needles, or passed to a baby through birth or breastfeeding. HIV weakens the immune system (the body’s defence system against illness and infection). The body can’t fight infection or disease without a strong immune system. If it’s not treated, someone with HIV can develop AIDS. While there’s no cure, treatment can help people live long and healthy lives.

To learn more, see HIV.

HIV Pre-Exposure Prophylaxis (PrEP) is a drug that helps prevent HIV for people with a high ongoing risk of getting the virus. It is a pill taken once a day. The prescription is available to Albertans at high risk of getting HIV, at no cost. For more information on HIV PrEP and sexual and reproductive services and resources throughout Alberta, visit Sexual and Reproductive Health.























Helpful Tools


STI Tool

Learn more about some common sexually transmitted infections.

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