08 HPV VACCINATION

Cervical cancer is the 10th most common cancer affecting women in Singapore1. Most cervical cancer is caused by infection of the cervix (opening or neck of the womb) with a virus known as human papilloma virus (HPV). HPV is very common, and most women who are sexually active will get a HPV infection at some point in life. It is found on the genitals, but also fingers, hands, and mouth, hence can passed by any kind of sexual activity (including skin-to-skin contact).

There are over 100 types of HPV, but “high-risk types” may cause cancer, most commonly of the cervix, but rarely also of the vagina, vulva and anus (back passage). Most HPV infections will go away spontaneously, and often cause no symptoms. If HPV persists, it may cause abnormal cell changes, which in turn can become cancer.

Can HPV be treated?
No, there is currently no treatment to get rid of HPV. However, in most women, the virus can be cleared by your own immune system. The chance of clearing the virus relies on the strength of your immune system, which depends on:

  • Age (the younger you are, the more likely you are to clear the virus)
  • Cigarette smoking
  • Co-existing medical conditions that weaken your immune system (such as Diabetes or HIV)
  • If you are on medications that compromise your immune system (steroids, immunosuppressants)

Most women (50-65%) will clear a HPV infection within 1 year. Persistent infection, or if associated with abnormal cell changes on PAP smear, may require further examination to take a closer look at your cervix, known as colposcopy. Your doctor will discuss this with you if it is needed.

HPV Vaccination
There is now a vaccine available, protecting against 9 types of HPV: 7 “high-risk types” of HPV, and 2 “low-risk types” that cause genital warts. The different types of HPV are numbered, and those that are covered by the vaccine are:

  • 7 “high-risk” types: 16, 18, 31, 33, 45, 52, 58 (these cause 90% of cervical cancer)
  • 2 “low-risk” types: 6 & 11 (these cause 90% of genital warts)

The vaccination is an injection given into the muscle, usually in the upper arm.
The most common side effects of the vaccine include

  • Pain, redness, and swelling where the injection was given (which resolve on their own)
  • Headache, body aches, fever, feeling tired

Rarely, if you are sensitive to yeast, amorphous aluminium hydroxyphosphate sulfate, or polysorbate 80, you could develop an allergic reaction and you should not get this vaccination. It is also not recommended in pregnancy.

Who should take the vaccine?
Based on research, this vaccine is best recommended for females aged 9 - 26 years. As HPV is spread by any sexual activity, including skin-to-skin contact, it is most effective if received before any sexual activity. In this group of women, the vaccine decreases the chance of cervical cancer by 90%, and the risk of genital warts by 90%.

For girls aged 9 - 13 years, the vaccine is given in 2 doses, 6 months apart. For those aged 14- 26 years, 3 doses are required, and an additional dose is given 1 month after the first dose.

If you are above 26 years of age or have had previous sexual activity, and wish to take the HPV vaccination, speak to your gynaecologist to find out if you are suitable.

What else do I need to know?
As the vaccine does not protect against all types of HPV that cause cervical cancer, it is important to continue regular Pap smear tests every 3 years even after HPV vaccination.

References:

  1. Health Hub. “What Every Woman Needs to Know About HPV Immunisation”.
    https://www.healthhub.sg/live-healthy/312/HPV_immunisation_FAQ. Singapore Health Promotion Board.
    Accessed on 28th May 2018.
  2. NHS UK. “HPV Vaccine.” https://www.nhs.uk/conditions/vaccinations/hpv-vaccine-cervarix-gardasil-safety.
    Accessed on 28th May 2018.
  3. Gardasil 9. https://www.gardasil9.com.
    Accessed on 28th May 2018.