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STD/STIs:  The Basics

Sharing STD/STIs: NOT a good idea

Your Mom always told you sharing was a good thing, but when it comes to STD/STIs, here's one time when Mom's advice doesn't work. 

To understand how to protect yourself from STD/STIs it's important to understand what they are and how they are spread from partner to partner (aka transmitted).

STD/STIs -- there's more than one!

Did you know that there are more than 25 diseases that can be spread from sexual contact, and most commonly they are bacteria, viruses, or parasites?

There are a lot of STD/STIs out there and they all are a bit different. 

  • They can infect different areas of your body (like your throat, vagina, anus, penis, skin)
  • They can be spread in different ways
  • Some can be cured (meaning that you CAN get rid of them)
  • And some can't be cured but ARE treatable (meaning you can take medication to control the symptoms)
  • Symptoms are different -- if there are any symptoms at all, that's right -- you can have an STD/STI without any symptoms!
  • And the way health care providers test for them can be different too! 

So with STD/STIs if you know one, you DO NOT know them all!

Know the ABCs of common STDs/STIs

Why is it important to learn about the different STD/STIs?

Because a little knowledge can help you:

  • protect yourself from getting an STD/STI,
  • talk to your sexual partner(s) about preventing STD/STIs
  • talk to your health care provider about STD/STI testing

Your health care provider is the best source of knowledge on STD/STIs

We also recommend visiting the Health Information section of Planned Parenthood's website, or the Center for Disease Control (CDC)'s website for more great STD/STI information.  

Common STD/STI's.

To get you started, below is a list of some of the common STD/STIs -- the links will take you directly to the appropriate section of

Can I get an STD/STI from anal sex? oral sex? vaginal sex?

Yes, yes, and yes! Many people think that you can't get an STD/STI from oral sex but you can!

STD/STI symptoms ≠ no STD/STI

Do you think you are STD/STI free because you have no symptoms?

Think again.

Do you think it's okay to have sex without a condom because your partner doesn't have any symptoms of an STD/STI?

Not so fast.

The truth is that very often STD/STIs don't have symptoms!

It needs to be said again: STD/STIs CAN HAVE NO SYMPTOMS. 

Okay, one more time and you say it with us...go ahead, no one's watching you: STD/STIs CAN HAVE NO SYMPTOMS! That means you can't tell if you have an STD/STI or if your partner has an STD/STI just by looking. The only way to know for sure is to GET TESTED

Explore: Quizzes 'n More

Now that you know how STD/STIs are transmitted and that they might not have any symptoms, are you wondering if you could have one? Should you get tested? Planned Parenthood has created a quiz you can complete to help you decide: The Check from Planned

No matter what "The Check" says, if you're sexually active and have not been tested, GET TESTED! And bring your partner too! It can't hurt, and it's always good to know for sure!


How they spread, and spread, and spread...

Exactly how transmission from person to person happens is probably the most important thing for you to know.  Knowing how STD/STIs spread can help all of us stop their spread.  And keep you safe.

Some STD/STIs are more easily spread than others. However, there are two basic ways transmission occurs:

  • Through body fluids (fluid-borne STD/STIs are found in pre-semen, semen, vaginal secretions, or blood)
  • Through skin-to-skin contact

Bodily Fluid Transmission. 

Examples of STD/STIs that live in body fluids (aka fluid-borne) include but are not limited to Chlamydia, HIV and Gonorrhea. Fluid-borne STDs that gain access to an uninfected person's blood stream cause infection. Normal, healthy skin (like the skin on your thigh) can prevent a fluid borne STD/STIs from reaching your blood stream. But the areas of your body that commonly come in contact with your partner during sexual activity (like your mouth, penis or vulva, and anus) are covered with special type of skin called mucous membranes. Mucous membranes are different than normal skin because they allow pathogens (like fluid-borne STD/STIs) access to the blood stream. That means when body fluids (like vaginal secretions) of an individual infected with an STD/STI comes in contact with your mucous membranes, the fluid-borne STD/STI can enter your blood stream. Broken skin, like a sore or an abrasion, even really tiny ones are another way that fluid borne STD/STIs gain access to your blood stream.

Skin-to-Skin Transmission. 

Herpes Simplex Virus (HSV) and Human Papillomavirus (HPV) are STD/STIs that are spread through direct skin-to-skin contact. Skin-to-skin transmission means that the STD/STI is spread directly from the skin of the site of infection to the skin of the site of contact. That means if your partner has genital herpes and has penetrative sex with you, you can get herpes.  Or if you rub your genitals against someone else who has genital herpes, whether you experience penetration or not, you can get herpes.

 Move On!