What’s the difference between an STI and an STD?
Sexually transmitted infections (STIs) and sexually transmitted diseases (STDs) are terms which are often used interchangeably, but there’s a specific difference between the two: the term STI refers to a sexually transmitted infection, while STD refers to a sexually transmitted disease.
Specifically, STIs are viral or bacterial infections that are transmitted through sexual activity. This can include oral, vaginal, or anal sex, and any genital contact, even when penetration does not occur. STIs are extremely common, preventable, and treatable. Most are also curable.
So what is the difference between an infection and a disease? In simple terms, an infection occurs when a bacteria or virus first enters your body, and a disease occurs when you start showing symptoms of that infection. It’s important to note that not all infections will lead to a disease.
A good way to understand the difference between a sexually transmitted infection and a sexually transmitted disease is to look at HPV (human papillomavirus), and cervical cancer. HPV is an infection that can lead to cervical cancer, which is a disease. Similarly, HIV is an infection, while AIDS is a disease.
Because you still have an infection if you have a disease, but not the other way around, STI has largely overtaken STD in how we refer to these conditions.
Among the most common STIs, HPV is at the top of the list. Genital herpes, gonorrhea, chlamydia, HIV, and syphilis are other STIs. Pelvic inflammatory disease (PID)—a cause of infertility—is an STD that may result from infection with gonorrhea or chlamydia.
Because STIs are most often transmitted through sexual activity, the only way to completely prevent infection is to abstain from sexual activity. However, this approach isn’t successful or realistic for most people, and there are lots of ways to stay healthy while having sex.
For those who are engaging in sexual activity with new or multiple partners, using condoms correctly and consistently can help to reduce the risk of contracting STIs with every oral, vaginal, or anal contact. If you have any questions about how to use condoms correctly, the CDC website has a great visual tutorial.
Reducing your number of partners, engaging in mutually monogamous relationships, and receiving vaccinations against human papillomavirus (HPV), hepatitis B, and hepatitis A are additional strategies that can reduce the risk of STI infection.
If an STI does lead to an STD, it’s worth noting that most STDs are treatable, and some can also be cured. It’s important to talk through the treatment options with your healthcare provider if a diagnosis is made.