As can be deduced by their name, sexually-transmitted diseases (STDs) or infections (STIs) are transmitted primarily through sexual contact with an infected person.
However, some STIs can also be passed on by close physical contact, or even by fingers touching infected areas.
Once known as venereal diseases (from the Latin word venereus, which means “of sexual love”), STDs are mostly caused by viruses, bacteria or parasites.
They can cause a range of problems, from itching in the short term to infertility in the long run, and even death.
However, some patients may show no sign of infection at all.
This is dangerous as they can still infect other people.
In fact, it is hard to tell just by looking who has an STI.
The lack of symptoms can make an STI hard to diagnose.
And those who do have symptoms might be reluctant to see the doctor due to embarrassment.
Generally speaking, infections caused by bacteria and parasites can be cured, but those caused by viruses are usually incurable.
Here are some common STDs:
Gonorrhoea is caused by the bacterium Neisseria gonorrhoeae.
It can infect the genitals, rectum and throat.
It is a very common infection, especially among those aged 15 to 24.
Aside from sexual contact with an infected partner, gonorrhoea can also spread from mother to baby during childbirth.
People with multiple sex partners are at higher risk of getting this infection.
Symptoms include a purulent (or pus-like) discharge from the genitals, which may be foul-smelling; inflammation; redness; swelling; and painful or difficult urination (dysuria), which may include a burning sensation during urination.
However, some patients may never develop noticeable symptoms.
Gonorrhoea can be treated with antibiotics.
If left untreated, it can lead to pelvic inflammatory disease (PID, which can cause infertility), transmission to sex partners, a higher rate of miscarriages and prostatitis (inflammation of the prostate), among others.
Chlamydia is caused by the bacterium Chlamydia trachomatis.
It is known as a “silent” infection as most patients have no symptoms (asymptomatic) or signs of disease.
It can infect the cervix (in women), rectum or throat.
About 50-70% of the female population has asymptomatic cervicitis (inflammation of the cervix) due to chlamydia.
Sexually-active young people, those with multiple sex partners, and men who have sex with men, are at high risk of acquiring chlamydia.
Symptoms include unusual vaginal bleeding or discharge, urethral discharge, pain in the abdomen, painful sexual intercourse, proctitis (inflammation of the rectum), fever, dysuria or the urge to urinate more frequently than usual.
Around half of infected men will not have any symptoms.
Chlamydia can be easily cured with antibiotics.
Because many people with gonorrhoea also have chlamydia, treatment for both infections are usually given together.
If left untreated, chlamydia can lead to PID, tubal factor infertility, ectopic pregnancy and chronic pelvic pain in women, and epididymitis (inflammation of the epididymis) in men.
It can cause serious, permanent damage to a woman’s reproductive system.
Syphilis is caused by the bacterium Treponema pallidum.
It can be divided into stages (primary, secondary, latent and tertiary), with different signs and symptoms associated with each stage.
Primary syphilis starts as a painless sore known as a chancre, typically on the genitals, rectum or mouth.
Skin or mucous membrane contact with these sores, usually during sexual contact, causes the infection to spread.
Regional painless lymphadenopathy (swelling of the lymph nodes) typically develops one to two weeks after the chancre.
The chancre tends to heal spontaneously within two months.
If left untreated, syphilis will progress to the secondary stage with flu-like symptoms, fever, headache and sore throat, as well as anorexia, muscle pain, lymphadenopathy and a highly infectious generalised mucocutaneous rash that may resolve over a period of weeks to months.
The signs and symptoms of primary and secondary syphilis can be mild and might go unnoticed.
There are no signs or symptoms during the latent stage.
A small percentage of cases progress to tertiary syphilis, which is characterised by a chronic inflammatory response that can destroy pretty much any organ or tissue, and can result in death.
An infected mother can transmit the disease to her fetus, resulting in either death or congenital syphilis.
Syphilis is curable with antibiotics, but any damage to the body is irreversible.
Genital herpes is caused by herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2).
It is spread through direct contact with blisters, ulcers, mucus or vaginal secretions, usually during sexual contact.
The most obvious symptom is a cluster of small painful blisters around the genitals and buttocks, which will become shallow, painful ulcers before scabbing over.
Other symptoms include itching, discomfort in the genital area, flu-like symptoms such as feeling unwell, headaches, and back and leg pain.
However, most infected people either do not have any signs or symptoms, or only mild ones, although they can still spread the disease.
Even if the sores disappear, the virus probably remains in the body for life.
There is no treatment for herpes.
Bathing in warm salt water can help minimise the pain and discomfort.
Complications can include transmission to sex partners and newborns, eye problems, proctitis and a higher miscarriage rate.
Infection with the human immunodeficiency virus (HIV) causes acquired immunodeficiency syndrome (AIDS).
It is one of the deadliest STDs in history.
HIV infects immune cells known as CD4+ T cells.
When these cells decrease to below 200 cells per millilitre of blood, the immune system is compromised, thus making the body susceptible to any kind of infection, which will eventually result in death.
HIV is spread through direct contact with infected blood, semen and vaginal fluids.
While the transmission rate of HIV during vaginal intercourse is low under normal circumstances, it is significantly increased if one of the partners has genital ulcers or other genital lesions.
Symptoms include flu-like symptoms, tiredness, fever, chills, night sweats, rapid weight loss, decreased appetite, and white spots or unusual marks in the mouth, among others.
There is currently no cure for HIV, although treatment can help patients live longer.
If a person is HIV positive, it means that they carry the virus and can pass it on; it doesn’t necessarily mean that they have AIDS.
The time from HIV infection to the development of AIDS varies.
Some individuals develop AIDS within a year, while others remain completely asymptomatic even after 20 years.
Genital warts are caused by certain types of human papillomavirus (HPV).
It is most commonly transmitted through penetrative sex and direct contact with infected skin.
Genital warts appear as bumps around the genital area, which may be flat or raised, single or multiple, or clustered together with a cauliflower-like appearance.
They may be either painless or cause some irritation.
They can be treated by applying topical medicine or removal with cryotherapy or laser.
If the wart recurs, an injection of a type of interferon can be used.
If left untreated, it can lead to transmission to sex partners and newborns, more warts or cervical cancer.
Vaccines against HPV are available.
Trichomoniasis is caused by the parasite Trichomonas vaginalis.
It usually infects the vagina in women and the urethra in men.
Aside from sexual contact, it can also be spread through sharing damp towels, bathing suits or wash cloths with an infected person.
While most men are asymptomatic, some may experience urethral discharge, mild discomfort and/or abnormal swelling in their genitals.
In women, symptoms may include green to yellow discharge with bad odour, vaginal itching, dysuria, genital inflammation and red spots on their vaginal walls.
Vaginal trichomoniasis has been associated with childbirth problems like premature rupture of membranes, preterm delivery and low birth weight of baby.
Trichomoniasis can usually be cured with metronidazole.
Prevention and pregnancy
STDs are very common in our society, hence prevention and timely treatment are very important.
It is particularly important for pregnant women to be checked for STDs as such infections can affect both mother and child.
They can cause early labour and complicate delivery.
Many STDs can also be passed from mother to baby, whether during the pregnancy itself, during childbirth or after the baby is born.
STDs can cause babies to be stillborn or have low birth weight, neurologic problems, blindness, liver disease or serious infections.
But there are treatments available to minimise these risks.
Treatment during pregnancy can cure some STDs and lower the risk of passing the infection to the baby.
There are many preventive measures we can all follow, such as:
- Avoiding having multiple sex partners
- Using latex condoms during sexual intercourse
- Washing the genital area before and after sexual intercourse
- Avoiding direct and sexual contact with a person who has an STD
- Avoiding sharing towels or underwear
- Getting help if you have a problem with drug or alcohol abuse
- Communicating openly with sex partners, including whether both of you have been tested for STDs.
Equally importantly, never be embarrassed to consult your doctor about an STD.
Remember, STDs do not discriminate.
Associate Professor Dr Mohammad Nazmul Hasan Maziz is a medical microbiologist and deputy dean of the Perdana University Graduate School of Medicine. This article is courtesy of Perdana University, which is celebrating their 10th anniversary this year. For more information, email email@example.com. The information provided is for educational and communication purposes only and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.