Sexually transmitted diseases can be hard to talk about. In many ways, there's still a certain sense of taboo whenever the topic comes around. This is especially true in Asian countries like Singapore.
Such a lack of familiarity can become an issue. Many individuals aren’t well-informed about the various types of STIs that can be contracted, as well as the types of treatment and preventive measures available.
A number of DoctorxDentist readers have posted questions pertaining to sexually-transmitted illnesses. Dermatologist Dr Tan Wei Sheng shared his professional opinions.
In Singapore, vaccines are available for certain infections
Vaccines are available for certain types of infections. They include Hepatitis A, Hepatitis B, and Human Papilloma Virus (HPV).
Your doctor might recommend you to go for vaccination if he/she feels that your situation requires it.
If you practice oral-anal sex, you are at risk of Hepatitis A
If you practice rimming (oral-anal sex), there's a chance that you might contract Hepatitis A. This condition causes liver inflammation. 
Generally, most health screening packages will let you know through a blood test if you are already immune to Hepatitis A or require vaccination.
Vaccination for Hepatitis B consists of injections over 6 months
Hepatitis B is another infection which can be transmitted through sexual intercourse. A blood test will let you know if you require vaccination, which is a series of 3 injections over 6 months.
HPV infects more people than you might expect
The Human Papillomavirus (HPV) virus is spread through skin contact during sexual intercourse. It is estimated to have infected 1 in 10 women in Singapore. 
Men aren't safe from HPV either, as it infects both genders and can lead to potentially serious diseases including cancer.
There are low and high-risk subtypes of HPV
Low-risk subtypes of HPV can cause common infections including viral warts and genital warts.
The high-risk types are responsible for responsible for cervical, anal, vaginal, and vulvar cancers. 
Vaccines can safeguard you from both low and high-risk subtypes
Gardasil 4 and Gardasil 9 are the vaccines that can protect you against both the high and low-risk subtypes of HPV.
Typically, they are licensed for use in males and females aged 9-26. If you're above 26, you can still consult your doctor about possibly receiving the vaccine.
Ideally, HPV vaccines are taken before you're sexually active
Taking the vaccine before being sexually active means that you can get the most out of the protection.
The vaccine is usually given in a series of 3 injections over 6 months and is known to be safe and well-tolerated.
PEP medication is an effective measure against HIV
Post Exposure Prophylaxis (PEP) is a course of anti-HIV medication that's taken a month after high-risk sexual exposure to HIV. Essentially, it aims to prevent the HIV virus from infecting you after being exposed to it. 
Remember, PEP is normally only for high risk of HIV exposure
PEP is usually only reserved for patients who have been in high-risk exposure to HIV. There's more than 1 in a 10,000 chance that you might contract HIV from a single encounter, so a thorough consultation will need to be carried out before you need PEP.
Doctors will need details of sexual history during the examination
In order to assess if you need PEP, doctors need to know a detailed history of the nature of sexual exposure, including characteristics of the sexual partner in order to determine the level of risk.
Where does the highest risk of HIV come from?
Generally, the highest risk comes from unprotected anal sex (both for the receiver and giver). On the other hand, the lowest risk of contracting the disease comes from oral sex. Other factors that increase the risk of exposure include broken skin or cuts at the genital area or the mouth.
PEP must be performed right after exposure
The sooner you undergo PEP after the sexual exposure, the better. The effectiveness of the medication has been shown to subside within a 72-hour period.
After this timeline, the medication has no benefit. Additionally, PEP carries a small risk of side effects (which is why it's reserved for high-risk exposures).
Ultimately, immediate action is necessary once you suspect that you might be at risk of contracting a sexually-transmitted disease.
The best thing would probably be to seek preventive measures even before being sexually active. Seek treatment and evaluation from an experienced doctor before it’s too late.
Article medically reviewed by Dr Tan Wei Sheng.
1. M G Brook. Sexually acquired hepatitis. Tropical Medicine Series. Aug 2002.
3. Eileen M. Burd. Human Papillomavirus and Cervical Cancer. Clin Microbiol Rev. Jan 2003.
4. Mark J Siedner. et al. HIV post-exposure prophylaxis (PEP). Nov 2018.