An Overview of STIs


The Basics

Two women kissing on lips in a kitchen.

Sexually transmitted infections (STIs) are infections that can be spread through sexual contact such as intercourse, oral sex, kissing, or shared sex toys. Also referred to as sexually transmitted diseases (STDs), these conditions are more often asymptomatic than not, which means an infected individual does not show signs of infection. To contract an STI, one must come in contact with the bodily fluids of another individual who is already infected or has signs of infection. A sexually transmitted infection can be passed through bodily fluids such as blood, semen, or vaginal fluid, and are caused by bacteria, parasites, and viruses. The most common STIs are chlamydia, syphilis, gonorrhea, trichomoniasis, Genital Herpes, human papillomavirus (HPV), and human immunodeficiency virus (HIV). Several STIs, such as HIV and syphilis, can be transmitted from mother to infant during childbirth through blood or tissue transfer. STIs can have serious negative consequences on a person’s reproductive health. According to the World Health Organization, 357 million new cases of gonorrhea, chlamydia, syphilis, and trichomoniasis occur every year.1 However, over 30 STIs exist, and over one million worldwide people contract a new infection every year.1 It is important for anyone who is engaging in any type of sexual activity to be aware of the different STIs, their symptoms, their treatments, and how to prevent their transmission. Due to their potentially serious effects, you should get tested for STIs if you are sexually active. Planned Parenthood recommends that a sexually active individual gets tested at least once a year.4 STIs can be dangerous, but if you get tested, use protection, and communicate with your partner, you can drastically reduce your chances of contracting an infection. 

Black man wearing a white coat and stethoscope

Prevention and Protection

Maintaining a healthy sex life can be very fulfilling, and ensuring that you are being safe while having fun can give you peace of mind. There are many stigmas surrounding STIs and getting tested. Because of this, some fail to engage in safe sex and get tested. However, there are many ways to prevent transmission and infection. Some of these methods are listed below:

Reception of vaccination. Gloved hand holds receiving arm.
  • Being educated about the risks of engaging in sexual behaviors can help you understand how to effectively protect yourself and your partner.
  • Getting vaccinated against human papillomavirus and hepatitis B
  • PrEP taken prior to being exposed to the HIV virus can reduce the risk of HIV infection by over 90%; PEP can reduce the risk of HIV infection by over 90% after being exposed to the virus.
  • Male circumcision has been shown to reduce the risk of HIV infection in males who have sex with females by 60%.1

  • Using male condoms, female condoms, or dental dams during every sexual encounter.

  • Getting tested once a year and making sure that your partner has been tested before engaging in sexual behaviors with them.

  • Remaining abstinent is the only way to guarantee that no STIs will be transmitted through sex. Entirely “safe” sex does not exist. Using protection can only lead to “safer” sex.

Upward facing palm holds condom. A man in bed lays in background.

Some people feel that they do not need to use any protection when they are with a long-term partner. However, only stop using protection once you and your partner have both been tested and can trust one another. Open communication about STIs and safety with your partner(s) is key to maintaining your sexual health.


Person in nude undergarments grasping their torso

The most effective methods of prevention include abstinence, vaccination, limiting sexual partners, and mutual monogamy.3 Common STI symptoms include unusual vaginal discharge, urethral discharge, lower abdominal pain, inflammation, painful urination, itching, and redness.1 Some STIs pose an extra risk because they can increase the chances of acquiring HIV. These STIs include herpes simplex virus 2 and syphilis. Some STIs such as chlamydia can be treated for up to four weeks, while HIV is a lifelong virus that has no cure.3 According to the CDC, pelvic inflammatory disease or PID can be caused by untreated STIs. PID can be cured but it must be treated early or it can lead to infertility and ectopic pregnancy.6

Wrapping it All Up

Banana wrapped in condom. On condom "safe sex" is written

The chances of acquiring an STI are reduced when a sexually active person is educated about the risk of transmission. If a person does acquire an STI, he or she can take appropriate action to reduce the risk of spreading the infection to others.2 Furthermore, most STIs are curable and do not lead to complications if treated early. Simply getting tested as well as assuring that you are practicing safe sex can drastically decrease your chances of getting an infection. We hope our overview of the STIs is helpful to you; however, if you believe yourself to be at risk of contracting an STI, it is best to immediately seek the help of a healthcare professional at a clinic or doctor’s office.

To learn more about STIs, watch the video below!


  1. “Sexually Transmitted Infections (STIs).” World Health Organization. World Health Organization, Aug. 2016. Web. 18 Jan. 2017.
  2. LeVay, Simon, Janice I. Baldwin, and John D. Baldwin. “Sexually Transmitted Diseases.” Discovering Human Sexuality. 2nd ed. Sunderland, MA: Sinauer Associates, 2012. 469. Print
  3. “How You Can Prevent Sexually Transmitted Diseases.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 31 Mar. 2016. Web. 18 Jan. 2017.
  4. Planned Parenthood. “How Often Do I Need to Get Tested for STDs?” Planned Parenthood. N.p., 15 Dec. 2013. Web. 24 Jan. 2017.
  5. “Can I Get an STI If…” Can I Get an STI If… | Options for Sexual Health. N.p., n.d. Web. 07 Feb. 2017.
  6. “Pelvic Inflammatory Disease (PID) – CDC Fact Sheet.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 23 May 2016. Web. 07 Feb. 2017.

Last Updated: 21 February 2017.