Sexually transmitted diseases (STDs), also known as sexually transmitted infections (STIs), are infections  that spread through sexual contact. They are passed from one person to another through various forms of sexual interaction, not just intercourse. This can include contact with the penis, anus, vagina, mouth, and skin.
Although most forms of STDs are transmitted via sexual contact, some can also be passed through shared needles and pregnancy  when the person is already infected. Transmission and treatment mainly depend on the type of infection.
Some STDs are very contagious and can cause serious illnesses right away, while some can lay dormant for years without presenting any symptoms at all but may cause severe damage to the body later on. Therefore, whether or not you are sexually active, it is best to keep yourself updated on the various STDs and the measures you should take to prevent them. It is also a good idea to get a check-up or STD screening if you are about to have sexual relations with a new partner or have had multiple sexual partners in the past, even if you don’t have any symptoms.
Since there are several types of STDs with varying symptoms, we’ve prepared this ultimate guide on everything you should know about the most common infections, as well as treatment and prevention measures to keep you and your partner safe.
What causes sexually transmitted diseases?
In general, STDs are caused by bacteria, viruses, and parasites that are transmitted during sexual activity. If left untreated, some of these infections, such as Human Papillomavirus (HPV), can lead to diseases such as cervical cancer and infertility. STDs that are passed through childbirth and pregnancy  can result in serious consequences for the baby, such as neonatal death and congenital deformities.
What are the most common types of STDs in Singapore?
A survey  conducted in 2018 found that the most common STDs in Singapore are chlamydia, gonorrhoea, syphilis, genital warts, and genital herpes. Although there are over 20 STIs and STDs worldwide, in this article, we will only cover these five, as well as hepatitis B and human immunodeficiency virus (HIV). Let’s delve into these seven different types of STDs and take an in-depth look at the symptoms as well as treatment options of each.
Chlamydia is caused by a bacterium known as Chlamydia trachomatis . It is one of the most common forms of STI that both men and women can get. This is mainly because it can be transmitted through several types of sexual contact, including oral sex. This means that it is not only passed through ejaculation but can also be transmitted through skin-to-skin genital contact or saliva. It is also possible for an infected mother to pass it on to her newborn during childbirth.
This infection can have serious consequences for a woman if left untreated. This includes permanent damage to a woman's reproductive system. In many cases, chlamydia does not have any symptoms, even though it can have serious health consequences without them. It may take several weeks for symptoms to appear, with some differences in men and women.
Symptoms of chlamydia
- Penis discharge
- Burning sensation during urination
- Pain and swelling in either one or both testicles
- Unusual vaginal discharge
- Burning sensation during urination
Testing and treatment for chlamydia
Chlamydia can be detected through laboratory testing such as vaginal or anal swabbing or urine tests. If you or your partner have any symptoms above or have any reason to suspect chlamydia (such as a previous sexual partner receiving a chlamydia diagnosis), see your healthcare provider as soon as possible to get tested. This is important because chlamydia can have no symptoms at all, and the only way to know is through these tests.
Chlamydia is highly treatable and curable. Antibiotics such as doxycycline or azithromycin are commonly prescribed to treat chlamydia. While you are on treatment, you will usually be advised to avoid sexual contact until you have finished the course. If you are pregnant, still have symptoms, or didn’t take your antibiotics properly, you may be recommended a repeat test to check if you are still infected with chlamydia.
Gonorrhoea is another sexually transmitted infection (STI) that is widespread in Singapore as well as the rest of the world. It is caused by the bacterium Neisseria gonorrhoea . Similar to chlamydia, gonorrhoea spreads through various types of sexual contact, including vaginal, anal, and oral sex. It also infects both men and women and can be spread from an infected mother to her newborn.
Gonorrhoea can lead to severe health problems and complications if it does not get treated. This includes pelvic inflammatory disease (PID) in women, which can cause infertility. Untreated gonorrhoea can also increase the chance of HIV  (human immunodeficiency virus), which can then lead to AIDS (acquired immunodeficiency syndrome).
The symptoms of gonorrhoea vary, and in many cases, they do not appear. When they are present, they can be different for men and women.
Symptoms of gonorrhoea
- Pain and burning during urination
- Unusual thick discharge from the penis that may be green or yellow
- Painful or swollen testicles
- Unusual thin or watery vaginal discharge that may be green or yellow
- Pain and burning during urination
- Pain or tenderness in the lower abdomen
- Unusual bleeding between periods, heavy periods, or bleeding after sex
Testing and treatment of gonorrhoea
Gonorrhoea can be detected and diagnosed through laboratory tests such as taking swabs of the genitals or the mouth and throat areas, as well as urine samples. Gonorrhoea is also easily cured through antibiotics such as ceftriaxone, which is an injection.
Gonorrhoea can still be spread while you’re on this medication, so it’s best to wait for seven days before you have sex again. Your doctor may recommend a repeat test after three months to determine whether the infection has completely cleared.
Find out more about gonorrhoea in men here.
Syphilis is caused by the bacterium Treponema pallidum , which causes infection when it comes into contact with broken skin or mucous membranes, typically in the genital area. Syphilis is commonly transmitted through sexual contact, but it can also be spread in other ways, such as from a mother to her newborn. It can be dangerous if left untreated and can cause serious health problems. There are four stages of syphilis, each with varying symptoms.
Symptoms and stages of syphilis
In the first or primary stage of syphilis, those with this infection may notice a single or multiple sores that appear on the penis, vagina, anus, rectum, lips, or inside the mouth. They are usually firm and round without causing any pain. Although these sores often naturally heal within 3 to 6 weeks, it is necessary to seek treatment to prevent the infection from progressing to the next stage.
In the secondary stage, those with syphilis usually develop red or reddish-brown skin rashes or sores in the mouth, vagina, and anus. They may also be on the palms of your hands and the bottom of your feet. They are usually mild and may not be noticeable. Other symptoms at this stage include:
- Swollen lymph glands
- High fever
- Sore throat
- Hair loss
- Weight loss
- Muscle aches
If syphilis is not treated, it may progress to the latent stage. This is when syphilis remains in the body for a period of time but does not have any symptoms and can be spread from one infected person to another.
Although several people who do not get treatment for syphilis do not progress into the tertiary stage, there is a chance it can happen. There can be serious health consequences during this stage, which can develop 10-30 years after the infection starts. The infection can affect the organs such as the brain, heart, and nervous system, causing damage and even death.
Testing and treatment for syphilis
Syphilis can be tested through a blood sample, where your doctor will collect a small amount of blood that will be tested in a laboratory. As syphilis can affect the brain and nervous system, your doctor may also order a CSF (cerebrospinal fluid) test . This is a test to get a sample of the fluid in your brain and spinal cord, done through a lumbar puncture procedure (also known as a spinal tap).
If you have been exposed to syphilis, but your blood test is negative, your doctor may recommend a repeat test after two weeks as it may take time for the antibodies to develop. If you are positive, you will likely be treated with antibiotics such as penicillin, which effectively clears the infection. Depending on the stage of syphilis infection, there may be other treatment methods as well, which your doctor will explain to you.
4. Genital warts
Genital warts are a very common STI caused by certain strains of the human papillomavirus (HPV) . HPV is a group of viruses, where some strains can cause warts to develop on or around the genital and anal areas. Genital warts are very contagious and are transmitted through vaginal, anal, oral sex, and skin-to-skin genital contact.
Although genital warts often clear up on their own, HPV infections itself are often not curable and may lead to more genital wart outbreaks in the future, or other complications due to the HPV. As genital warts are a symptom of HPV, the virus can also be transmitted through sexual contact, even if there are no warts present. Take note that not everyone with an HPV infection will develop visible warts.
Symptoms of genital warts
- Cauliflower-like growths that are flat or raised, usually appearing on the genital, anal, lips, and mouth areas. In men, they may be present on the penis or scrotum, while in women, they are often present on the vulva or inside the vagina. They are often flesh-coloured and bumpy in texture. They may also be very small and barely noticeable.
- Pain, bleeding, itching, discomfort, or tenderness in the affected area.
Testing and treatment of genital warts
In general, your doctor can diagnose genital warts through a visual examination. Other tests include a pap smear test to check the cervix, a colposcopy for a biopsy of the vagina, or an anal test to look inside your anus for warts.
Genital warts are not curable as HPV is a lifelong infection. Therefore, you may get recurring genital warts throughout your lifetime. Although there is no definitive cure for HPV, there are many types of treatment for genital warts. These include:
- Electrocauterisation: using electric currents to burn warts off.
- Cryotherapy: cold liquid nitrogen to destroy warts.
- Topical medicine: prescription cream to treat warts.
- Surgery: surgical removal of warts that don’t respond to other treatments.
Find out about HPV vaccination here.
5. Genital herpes
Genital herpes is a sexually transmitted infection (STI) that is caused by the herpes simplex virus (HSV ). The two main types of herpes simplex virus are HSV-1 and HSV-2. HSV-2 infections are most likely to lead to genital herpes. Genital herpes is commonly spread through skin-to-skin contact during sexual activity.
Several people with HSV infections are unaware that they have it because they do not have any symptoms. However, they are still able to spread it. If left untreated, genital herpes can cause painful genital ulcers. It can be especially severe  for those with suppressed immune systems, such as those with HIV. In rare cases, HSV can cause complications such as aseptic meningitis (inflammation of the lining of the brain).
Symptoms of genital herpes
- Genital pain or itching
- Small bumps or blisters that develop around the genitals, anus, or mouth
- Painful, oozing, and bleeding ulcers
- Pain during urination
- Vaginal discharge
- Body aches
- Swollen lymph nodes in the groin area
Testing and treatment of genital herpes
Genital herpes can be detected through blood tests where HSV antibodies can be found. Your doctor may also take a sample from a sore to check for HSV using a polymerase chain reaction (PCR) test .
There is currently no cure for genital herpes, but there are many treatment options to manage this infection. These include:
- Antiviral medicines to prevent outbreaks and reduce the risk of transmission to others
- Over-the-counter pain relievers to treat pain and discomfort due to genital herpes outbreaks
- Topical antiviral creams to minimise discomfort
Find out more about genital herpes in men here.
6. Hepatitis B
Hepatitis B is a liver infection caused by the HBV virus . It spreads through contact with blood or semen from one infected person to the other. This can happen through sexual contact as well as sharing needles or infected syringes or through pregnancy and childbirth.
Not everyone with HBV develops symptoms. It can be a short-term illness (acute) or can progress into a long-term (chronic) infection that may lead to serious health problems such as liver disease or cancer.
Symptoms of Hepatitis B
- Lack of appetite
- Jaundice (yellowing of the skin)
- Stomach pain and discomfort
Testing and treatment for Hepatitis B
In Singapore , newborns receive the Hepatitis B vaccine at birth, and vaccination is complete by the time they are six months of age. However, you may not have received it if you were born before October 1985. If unsure, consult your doctor to receive the vaccination as an adult. The vaccine is highly effective at preventing Hepatitis B infections.
Hepatitis B can be detected through blood tests to check if your infection is acute or chronic. If your doctor suspects liver damage, a liver ultrasound called a transient elastography or a liver biopsy to collect a small liver tissue sample may be done.
For those with Hepatitis B infections, treatment usually includes:
- Antiviral medications: medicines such as entecavir (Baraclude), tenofovir (Viread), lamivudine (Epivir), adefovir (Hepsera), and telbivudine can help treat Hepatitis B infections and protect the liver.
- Interferon alfa-2b (Intron A): a synthetic version of a substance naturally produced by the body to fight infection.
- Liver transplant: if your liver has been severely damaged from Hepatitis B, a liver transplant may be recommended.
7. Human Immunodeficiency Virus (HIV)
Human immunodeficiency virus (HIV) is an infection  that attacks the body’s immune system. It can develop into acquired immunodeficiency syndrome (AIDS) if it is left untreated and becomes advanced. HIV is spread through sexual contact with bodily fluids of a person who has HIV, such as blood, semen, and breast milk. It can also be spread through the sharing of infected needles, breastfeeding, and pregnancy. HIV targets the body’s white blood cells, thus weakening the immune system. Those with untreated HIV can easily become ill with infections and even cancers.
Stages and symptoms of HIV infection
Primary infection (acute HIV):
- Muscle aches
- Joint pain
- Sore throat
- Painful mouth sores
- Swollen lymph glands
- Weight loss
- Night sweats
Clinical latent infection (Chronic HIV):
At this stage of infection, HIV is still present in the body, but most people do not have any symptoms. This stage can last for several years if they are receiving antiretroviral therapy (ART).
Testing and treatment for HIV
Blood tests are the most common way to diagnose HIV, as they can show antibodies to the virus. Early testing is crucial so that you and your doctor can discuss and develop a treatment plan that can help you start treatment to fight HIV and prevent the spreading of the virus.
There is currently no cure for HIV infection. However, there are several options today for HIV prevention and treatment. It has become a very manageable condition that allows people to live with HIV without it progressing to AIDS for the rest of their lives. There are known as antiretroviral therapy (ART) medications that allow those with HIV to develop a low or undetectable viral load, meaning they can’t transmit it to others and they can stay healthy.
Check out our complete guide to HIV in Singapore here.
How to prevent STDs?
Now that you know the different types of STDs, as well as their symptoms and treatment options, you may be asking yourself, how do I prevent them? While abstaining from sex is the most effective way to spread any infection, it is not a feasible option for those who are sexually active or wish to embark on a new relationship. Therefore, here are some recommended options to decrease your chances of becoming infected with STDs:
- Practise safe sex
Practising safe sex includes always wearing a condom and using dental dams during oral, anal, and vaginal sex. Taking these measures can significantly reduce the chances of spreading an STD, although it is not impossible. Communicate openly and honestly with your partner about safe sex practices before starting a new sexual relationship to prevent any conflict down the line.
- Get regular check-ups and screenings
If you are about to start a new sexual relationship or have multiple sexual partners, or if you suspect your partner has an infection, it’s a wise idea to get an STD screening and medical check-up. Even if you have no symptoms, it can provide peace of mind to you and your partner and curb any infection before it has spread. Speak to your doctor about scheduling regular STD screenings and check-ups if you often engage in sexual activity with multiple partners.
Find out about STD testing in Singapore here.
- Seek treatment
If you have any symptoms of STDs, as outlined in the previous section, seek treatment immediately. It is best to treat any STDs as soon as possible to prevent them from worsening or spreading to others. STDs can have serious health consequences if left untreated, which is why it is best to undergo treatment as soon as they are detected. Know that certain STDs are very common, and your doctor can help you with a treatment plan as well as provide guidance to prevent it from further spreading or progressing to the next stage.
- Stay informed
Staying educated and aware of the different types of STDs (such as reading this guide) and knowing how they spread, symptoms to watch out for, and prevention techniques are all very important if you are in a sexual relationship or about to start one. This arms you with the right knowledge if you come into contact with an STD and helps you make responsible decisions to prevent you and your partner from becoming infected.
Concerned about STDs or need to schedule a screening? Contact us at Dr Ben’s Medical Clinic today for a consultation.
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