There are 2 main strategies in the prevention of cervical cancer:

• Human Papillomavirus (HPV) vaccination
• Cervical cancer screening via Pap test or HPV test

In my practice, I have encountered much confusion from my parents regarding the above. This article aims to address the common questions regarding HPV and HPV vaccination, while Part 2 will aim to address the questions regarding cervical cancer screening.

Questions regarding HPV & HPV vaccination:

• How does the HPV vaccination help to prevent cervical cancer?
  • HPV is a virus that can infect the cervix, causing abnormal changes which can lead to cervical cancer.
  • Most cervical cancers are caused by HPV infection.
  • Vaccinating against the HPV virus can help lower the risk of HPV infection, thereby lowering the risk of cervical cancer.
• Is HPV only transmitted through sexual intercourse?
  • No, HPV can be transmitted through close skin-to-skin or genital-to-genital contact, even without having sex.
  • HPV can be transmitted through oral, vaginal or anal sex, as well as through sex toys.
• Does HPV only cause cervical cancer?
  • No, HPV can also cause cancers of the cervix, vulva, vagina, penis, anus and the throat, depending on the transmission as mentioned above.
  • HPV can also cause warts on the genitals or elsewhere, depending on the transmission.
• At what age is HPV vaccination recommended?
  • The recommended age range for HPV vaccination is from age 9 to 26.
  • As the vaccine is most effective before getting infected with HPV, it is recommended to get the vaccine early.
  • The Gardasil 9 can be given up to age 45.
• How many different types of HPV vaccines are there and what are their differences?
  • There are 2 main types: Cervarix (HPV2 Vaccine) and Gardasil 9 (HPV9 Vaccine)
  • Cervarix is also called HPV2 as it protects against 2 HPV subtypes – HPV 16 and 18.
  • Gardasil 9 is also called HPV 9 as it protects against 9 HPV subtypes -HPV 6, 11, 16, 18, 31, 33, 45, 52 and 58

HPV Subtypes	Disease
6, 11	Cause approximately 90% of genital warts
16, 18	Cause approximately 70% of cervical cancers
31, 33, 45, 52, and 58	Cause approximately 20% of cervical cancers

• How many doses are there for HPV vaccination?
  • People younger than 15 should get 2 doses, at least 6 months apart.
  • People 15 and older should get 3 doses over 6 months.
• Do I need to restart the vaccination doses if I miss a dose?
  • No, the vaccination can be resumed without restarting the series.
• What are the side effects of the HPV vaccination?
  • The HPV vaccine can cause redness, swelling, or soreness where the shot was given.
• Am I completely safe from cervical cancer after completing the HPV vaccinations?
  • No, because the vaccines are not effective in clearing HPV infection that is already present before the start of vaccination and the vaccines do not protect against 100% of all types of HPV that are known to cause cervical cancer (as shown in the table above).
  • Therefore, regular cervical cancer screening is still recommended to detect any cervical cancer early.

Part 2 will be published next week addressing the common questions and misconceptions regarding cervical cancer screening.

References:

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