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Course: Class 12 Biology (India) > Unit 4
Lesson 2: Sexually Transmitted InfectionsSexually Transmitted Infections (STIs)
Brief overview of different sexually transmitted infections
This article provides an overview of:
- Curable STIs
- Incurable STIs
- Methods to prevent STIs
Key terms
Term | Meaning/Examples |
---|---|
Sexually transmitted infections (STIs) | Infections in which the pathogens are transmitted via sexual contact |
Curable STIs | Syphilis, gonorrhea, chlamydiasis, trichomoniasis |
Incurable STIs | Genital herpes, HPV, hepatitis B, HIV |
HPV | Human papillomavirus |
HIV | Human immunodeficiency virus |
Prevention of STIs | Avoiding multiple partners, using condoms, vaccinations |
Sex - a means of transmission for some pathogens
Pathogens are disease-causing microorganisms. In order for continued survival, they have to be transmitted from one person to another.
There are various modes of transmission of pathogens: air, water, insects, etc. Sexual intercourse is a convenient mode of transmission for some pathogens, because it involves the exchange of body fluids. The infections caused by these kinds of pathogens are called sexually transmitted infections (STIs).
Common curable sexually transmitted Infections
Out of the most common sexually transmitted infections, four are curable. These are syphilis, gonorrhea, chlamydiasis, and trichomoniasis. The first three are caused by bacteria.
Syphilis is caused by a bacterium called Treponema pallidum. It enters the body of a person through open sores or cuts on the skin in the genitals. The symptoms include sores and rashes. If left untreated, the disease can harm many organs in the body, including the nervous system. The most common treatment is with the antibiotic penicillin.
Gonorrhea is caused by the bacterium Neisseria gonorrheae. The symptoms are: painful urination, discharge from the genitals, and pain in the testes in men and in the abdomen in women. In addition, the rectum, eyes, throat, and joints may also be affected. The infection can also lead to infertility. Gonorrhea can be cured with antibiotics.
The causative agent of the third bacterial infection, chlamydiasis, is Chlamydia trachomatis. It too can be cured by antibiotics.
Trichomoniasis has similar symptoms as gonorrhea and chlamydiasis. However, this sexually transmitted infection is caused by a protozoan called Trichomonas vaginalis. It can be cured by antiprotozoal drugs like metronidazole or tinidazole.
Common incurable sexually transmitted Infections
Unfortunately, modern medicine can't cure all STIs yet. Notable among the incurable sexually transmitted diseases are genital herpes, hepatitis B, HPV, and HIV.
Genital herpes is caused by the herpes simplex virus. The most common symptoms are blisters in the genitals. There is no cure, but the symptoms can be managed by antiviral drugs.
HPV or human papillomavirus is a sexually transmitted infection caused by a virus of the same name. Most HPV infections are either asymptomatic or cause genital warts. However, some strains of HPV can cause cancer. There is no cure, but a vaccine is available.
Hepatitis B is a liver infection caused by the hepatitis B virus. Besides sexual contact, the virus can spread through infected needles as well. The infection can be either acute or chronic. Chronic infections can lead to cirrhosis or liver cancer. A vaccine can be used to prevent it.
The STI that has instilled the most fear in people's minds is probably HIV, an infection caused by the human immunodeficiency virus. It is transmitted through infected needles as well. The virus severely weakens a person's immune system, making them vulnerable to other infections. Although HIV is not curable, powerful treatments are available that drastically slow down the growth of the virus and allow the patients to lead a normal life.
Prevention is better than cure!
All sexually transmitted infections can be prevented if a few measures are followed. First and foremost, it is best to avoid sexual intercourse with multiple partners, especially partners that are strangers. Second, using condoms properly goes a long way in protecting one from STIs.
Some diseases like HPV and hepatitis B have vaccines. Getting these vaccines can protect one against at least these two infections.
It is also important to avoid sharing needles and syringes with other people, because some STIs are transmitted through that route.
Although some STIs are incurable and potentially deadly, if one follows these simple norms, one need not worry about contracting them.