An illustration of the three bacterial STDs.

Bacterial STDs: What You Need to Know

Just like there are different microorganisms that cause most infections and diseases, they’re also the cause of different kinds of sexually transmitted diseases and infections, including bacterial STDs. Here’s a breakdown of what bacterial STDs are and which STDs are bacterial.

What is a bacterial STD?

Most STDs fall into one of three categories: bacterial, viral or parasitic. STDs fall into one of these three categories based on what the cause of the infection or disease is: bacteria, a virus or a parasite. Bacterial infections include strep and staph infections, as well as STDs like gonorrhea and chlamydia. Viral infections include the common flu and cold, as well as sexually transmitted infections like herpes and HIV. Parasitic infections include malaria and pinworms, as well as STDs like trichomoniasis or pubic lice.

Which STDs are bacterial?

There are three common bacterial STDs.

An illustration of the bacterial STD gonorrhea


Gonorrhea is a bacterial infection and one of the most common STDs in the US. The CDC estimates that there are more than 800,000 new cases of gonorrhea annually. Gonorrhea is commonly spread through different kinds of sexual activity, including vaginal, anal and oral sex. As a result, gonorrhea can infect the vagina, penis, throat, mouth, and even eyes.

The bacteria that causes gonorrhea is transmitted through sexual fluids, including semen, pre-cum and vaginal fluids. While practicing safer sex can reduce your risk of transmission or exposure to gonorrhea, the best way to prevent contracting or passing the infection to someone else is to know your status and that of your partner or partners.

Like many STDs, gonorrhea is commonly asymptomatic, meaning you or a partner might not experience any gonorrhea symptoms related to the infection, but that doesn’t mean the infection isn’t present and can’t be passed to others. Getting tested is the only way of knowing for sure.

An illustration of the bacterial STD Chlamydia.


Chlamydia is another extremely common STD in the US. The CDC estimates that nearly 3 million Americans, typically between the ages of 14 and 24, contract the infection every year. Like gonorrhea, chlamydia is spread through different kinds of sexual activity, including vaginal, anal and oral sex, because the bacteria that causes the infection is passed through sexual fluids. Again, like gonorrhea, chlamydia symptoms can be mild or nonexistent, so the only way to know for sure if you or your partner has it is to get tested.

An illustration of the bacterial STD Syphilis.


Syphilis is a bacterial infection caused by the bacterium Treponema pallidum. While at one point syphilis infections were so low that eradication of the disease was thought to be possible, infections have been on the rise since 2000. In 2015, there were 74,000 new cases of syphilis reported in the US. That’s a dramatic rise from 6,000 cases in 2000.

Syphilis can be passed through unprotected vaginal, anal and oral sex. It is spread from sexual skin-to-skin contact when your vulva, vagina, penis, anus or mouth touches someone’s syphilis sores. Though safer sex practices can help reduce the risk of transmission, prophylactics do not always cover these sores, and people who have sores often can’t see or notice them, so they might not even know they have any kind of infection. Don’t wait until syphilis symptoms occur! Syphilis can cause serious health issues if it’s left untreated, so it’s important to get tested frequently and treated if necessary.

The good news about bacterial STDs

Fortunately, bacterial STDs can easily be treated with antibiotics. However, in order to get treated, you need to get tested. When it comes to bacterial STDs, you can get tested for each STD individually or order a test that covers multiple STDs at once. For instance, chlamydia and gonorrohea can be ordered as a twin panel test, or order a 10 panel that covers all of the most common STDs.  These types of testing options are not only convenient and cost effective, they also help you understand whether you need to treatment and which treatment options are right for you.

With bacterial STDs, there’s no reason to prolong getting tested, because you’re only prolonging your time spent waiting for treatment. Even if you aren’t experiencing symptoms, these infections can be harmful to you and anyone you pass them to, so it’s important to get tested regularly.