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Five common STIs (sexually transmitted infections) to watch out for

Posted on: December 01, 2021

There are many types of sexually transmitted infections, some curable, some not, some have horrific symptoms, some have none at all. Here are five common STIs:

HIV (Human immunodeficiency virus)

HIV is the most common sexually transmitted infection (STI) known by all and sundry. It causes disease in a roundabout way by attacking the immune system, leaving its host extremely vulnerable to infections and disease. This infection can be transmitted through sex, blood transfusion, pregnancy (if the mother is not using HIV medication) and sharing of sharp objects like needles and syringes and less commonly through breastfeeding.

Symptoms of HIV-infection:1

  • Some people have no symptoms at all during the early stage of infection
  • About two-thirds of people will have a flu-like illness within 2-4 weeks after infection

The only way to know for sure if you have contracted HIV is to get tested. If left untreated, HIV can lead to the disease AIDS (acquired immunodeficiency syndrome2.


With treatment, the amount of HIV present within the body can be reduced to a very low level. People who take HIV medicines as prescribed and get an undetectable viral load have effectively no risk of transmitting HIV to an HIV-negative partner through sex. Though to keep the viral level continuously undetectable, the person should never stop taking their medicines and go as often as recommended for a viral load test. This has enabled couples where one partner is negative and the other positive to continue to have a healthy sex life and in some cases to use condoms without any lingering fear from the HIV negative partner.


Chlamydia is an STI caused by chlamydia trachomatis (c. trachomatis). Chlamydia is the most common infectious cause of sexually transmitted diseases globally.

Symptoms in persons with a vagina include:

  • Abdominal or Pelvic Pain
  • Extremely painful sex either occasionally or every time
  • Bleeding when you’re not on your period

Symptoms in persons with a penis include:

  • White, cloudy or watery discharge from the penis
  • Discomfort when urinating
  • Bulging in the testicles
  • Discomfort or bleeding in the anus


Chlamydia is easily treated with antibiotics prescribed by a doctor.


This is an STI caused by infection with the bacterium neisseria gonorrhoeae. It can affect the urethra, eyes, throat, vagina, female reproductive tract, anus. If left untreated, this STI is well known to cause infertility in persons with an uterus.

Symptoms include:

  • Pus-like discharge from the penis/vagina (white, yellow, beige, or greenish)
  • Swelling at the tip of the penis/testicles
  • A chronic sore throat
  • Discomfort/Pain while urinating
  • Persistent urination
  • Unusually heavy menstrual flow
  • Discomfort while having sex


Just like in the case with chlamydia, this is treated with antibiotics prescribed by a doctor.


is a bacterial infection caused by streptobacillus haemophilus ducreyi. It causes painful sores on the genitals and is only spread through sexual contact.


  • usually occur within four to ten days after contact
  • The sore begins as a soft, elevated bump that becomes a pus-filled, open sore with eroded or ragged edges
  • The sore can be very painful, although sometimes persons are not aware of its existence
  • Painful lymph nodes can sometimes occur in the groin.


This STI can be treated with antibiotics prescribed by a doctor.


Herpes is a chronic STI caused by the herpes simplex sirus (HSV). There are two types:

1) Herpes-type 1: transmitted through sharing straws, eating utensils, and kissing. It primarily causes oral herpes and is generally responsible for cold sores and fever blisters around the mouth and on the face.

2) Herpes-type 2: transmitted through sexual contact (anal, vaginal, or oral sex) and is generally responsible for genital herpes outbreaks.

Symptoms of the type 2 include:

  • Blisters on the penis or vulva
  • Blisters and sores on the woman's cervix (the lower end of the uterus that forms a canal between the uterus and vagina)
  • Pain/Discomfort while urinating
  • Sores around the mouth


Antivirals are the most effective treatment, however, note that that medication won’t cure the infection, only help lengthen the time between symptoms and lessen their severity.3

condom STI protection


Your safety is in your hands to reduce the risk of catching any STIs by making sure you are practicing safe sex. Here are the ways to achieve this:

  • Use a condom for any type of sexual intercourse.
  • Keep the number of sexual partners you have low.
  • Engage in honest conversations with any new partner(s) on your sexual history, particularly if any of you has or suspects you have an STI. Now is the right time to let yourselves know.
  • Go for STI tests before starting any committed sexual relationship.
  • Try as much as possible to avoid having sex when your judgment is impaired by drugs or alcohol.

On a final note, while HIV is rarely transmitted through oral sex, you can get many other STIs from oral sex. And, if you get faeces in your mouth during anus-mouth oral sex, you can also get hepatitis A and B, parasites like Giardia, and bacteria like shigella, salmonella, campylobacter, and e. coli.

facts about sexually transmitted infections

Credits for this article go to our partner Whispa,



A coalition of international partners with an interest in sexual and reproductive health