Common sexually transmitted infections (STIs)

A sexually transmitted infection (STI) is any infection spread primarily through sexual contact. One partner transmits the infecting organism to the other during sex (oral, vaginal, or anal).

STIs are some of the hardest infections in the world to catch as you have to be up close and personal to spread it. So why do STIs spread? The answer is likely because people don’t know how to recognize, treat, prevent, and avoid it. Or when they do, they often don’t do it effectively.

Moreover, not all infections affecting the genitals are considered sexually transmitted infections, and some are not related to sexual contact at all. Some of them are sexually related, which means that they are not transmitted during sex, but rather occur as a result. Here are some common STIs and and their symptoms that you should be knowledgeable about.

The most common type of sexually transmitted infections

There are at least 20 different STIs. They can be caused by viruses, bacteria, and protozoa. Some of the most common STIs are:

• Chlamydia
• Genital herpes.
• Genital warts or human papillomavirus (HPV). Certain high-risk types of HPV can cause cervical cancer in women.
• Gonorrhea.
• Hepatitis B.
• Syphilis.
• Trichomoniasis.
• Human immunodeficiency virus (HIV), which causes AIDS. Having other STIs, such as genital herpes, can increase your risk of HIV.

Other infections that may be transmitted through sexual contact include Hepatitis A, cytomegalovirus, molluscum contagiosum, Mycoplasma genitalium, Hepatitis C, and possibly bacterial vaginosis.

Bacterial STIs can be treated and cured, but STIs caused by viruses usually cannot be cured. You can get a sexually transmitted bacterial infection over and over again, even if you’ve had it in the past.

Key facts about STIs by WHO

• More than 1 million sexually transmitted infections (STIs) are acquired every day worldwide (1, 2).
• Each year, there are an estimated 376 million new infections with 1 of 4 STIs: chlamydia, gonorrhoea, syphilis and trichomoniasis (1, 2).
• More than 500 million people are estimated to have genital infection with herpes simplex virus (HSV) (3).
• More than 290 million women have a human papillomavirus (HPV) infection (4).
• The majority of STIs have no symptoms or only mild symptoms that may not be recognized as an STI.
• In some cases, STIs can have serious reproductive health consequences beyond the immediate impact of the infection itself (e.g., infertility or mother-to-child transmission)

SIDC’s response through STI testing and counseling

SIDC offers free counseling and testing for many sexually transmitted diseases such as HIV, hepatitis B and C, and syphilis. In addition, we provide safe and highly effective vaccines for hepatitis B and HPV, and also provide treatment and case management for people living with HIV.

We intervene at several levels: comprehensive sexual education, sexually transmitted infections and HIV/AIDS, pre- and post-test counseling; Safe sex/harm reduction and use condoms.

We target key populations, such as sex workers, men who have sex with men, and people who inject drugs; STI prevention education and counseling tailored to the needs of adolescents.