Originally published on April 5, 2017.
Every day, more than one million Sexually Transmitted Infections (STIs) are acquired worldwide (1). Even though the infections are common, knowledge about them may not be. Did you know the majority of STIs have no, or only mild, symptoms and may not be recognized (2)? Or that some infections like herpes simplex virus type 2 (which can cause genital herpes) and syphilis increase the risk of contracting other STIs like human immunodeficiency virus (HIV) (2)?
Knowing some STI basics may change the way you take precautions around sex in your own life.
First of all—what are we talking about when we talk about STIs?
STIs are a versatile group of infections that includes more than 30 different bacteria, viruses, and parasites (2). STIs are mostly spread through sexual contact (including all different forms of sex), but some of the same infections can also be transmitted non-sexually, for example through blood (like transfusions or shared needles), during birth, and during pregnancy via the placenta.
The most common curable STIs include syphilis, gonorrhea, chlamydia, and trichomoniasis, which can all be treated with different antibiotics (2). The four most common incurable STIs are all viruses: HIV, hepatitis B, human papillomavirus (HPV) and herpes. Although there is currently no therapy to eliminate these viral pathogens from the body, there are certain strategies to reduce or modify the symptoms. Talk to your healthcare provider if you have questions about what treatments might be best for you.
How does someone know if they have an STI?
The symptoms and progression of STIs differ by infection type, but some common symptoms are: vaginal discharge, urethral discharge, genital sores, or pain in the abdomen (2). STIs may cause no (or only mild) symptoms, so it’s important to get tested if you may be at risk for infection (2,3).
Someone can be infected with an STI for a long time without experiencing any symptoms. Without routine testing, infections may go untreated, leading to health complications and transmission to new sex partners.
Trusting an untested partner to tell you if they have an STI also means trusting all their untested ex-partners and all the untested ex-partners of their ex-partners and so on…
What happens if STIs go untreated?
In addition to the continued spread of infection to new partners, untreated infections can cause health problems.
Gonorrhea and chlamydia, for example, are major causes of infertility (1) and can lead to a higher risk of extrauterine (or ectopic) pregnancy (4, 5). Syphilis during pregnancy increases the risk for stillbirth and death of the newborn (6, 7).
STIs can also cause damage to non-reproductive organs. Syphilis can damage the eyes, brain, and nervous system (7). Chlamydia can cause inflammation of the lining of the liver, and gonorrhea can affect the joints and skin (8, 9). In some cases, such as with acquired immunodeficiency syndrome (AIDS), untreated HIV can be life threatening (10). HPV can cause cervical cancer, as well as cancers of the vulva, vagina, penis, anus, and throat (11).
What can I do to protect myself?
Understand your risk of infection by learning about STI basics (12).
Talk to your partner about how you will keep each other safe (13). Do you plan on being monogamous? Have you each been tested for STIs recently?
Use a barrier method (such as a condom) to decrease the risk of infection, particularly with new or untested sex partners (2,13). Some examples of barriers include external and internal condoms, dental dams, and gloves. They should be considered when you touch a partner’s genitals or share sex toys.
Get regular STI tests and retest after new sexual partners to minimize the risk of leaving any infection untreated (13).
Take PrEP (pre-exposure prophylaxis) if you are at increased risk for HIV (14). PrEP is a medication that you take daily to prevent infection with HIV (15).
Get vaccinated. Vaccinations are available to prevent Hepatitis B and nine strains of HPV (12).
Always be prepared! Several studies have shown people can be pretty sure they won’t have sex without a barrier method, but then change their mind in the moment (16, 17). It can be helpful to have barrier methods close at hand and a strong understanding of how to use them (it takes legitimate practice). Minimize the opportunities for reconsideration in the heat of the moment.
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