What is HPV?

Human papillomavirus (HPV) is a highly infectious virus that can infect both men and women with sexual experience. Most HPV infections do not produce any symptoms and are eliminated by our immune system. Persistent infection may lead to precancerous lesions or cancer. High risk HPV (types 16, 18, 31, 33, 45, 52, 58) can cause cervical cancer, vaginal cancer and vulvar cancer, anal or oropharyngeal cancer, while low-risk HPV (e.g. types 6, 11) can lead to condyloma acuminatum (genital warts).

Who needs to be vaccinated?

HPV vaccines are most effective for people who have not had sexual experiences and have not been infected with HPV, but they can still be administered to those who have had sex. Currently, 4-valent vaccine (Gardasil) is approved for females aged 9 to 45 years and males aged 9 to 26 years, while 9-valent vaccine (Gardasil 9) for females and males aged 9 to 45 years, and 2-valent vaccine (Cervarix) for females aged above 9 years. In addition, it should be noted that HPV vaccine can only prevent HPV infection, and thus prevent cervical cancer, genital warts and other anal and vaginal cancers.

What is the vaccination schedule for HPV vaccines? Can different brands be given as alternatives?

The HPV vaccine is usually administered in 3 doses over a period of 6 months. Failure to complete 3 doses or scheduled vaccination may affect the effectiveness of HPV vaccine. If you fail to receive the vaccination on schedule, please return to the clinic for consultation before continuing to receive the follow-up vaccination. In addition, HPV vaccines from different brands are not recommended to be given as alternatives for one another.

How long does vaccine protection last?

According to available research data, the protective capacity of bivalent vaccine Cervarix can last for at least 11 years, that of quadrivalent vaccine Gardasil for at least 12 years, and that of Gardasil 9 for at least 8 years. But whether they can last longer and whether booster is required in the future is still under investigation. The consensus at present is that no additional administration is needed.

Who should not get vaccinated?

Vaccination is not recommended for people who have experienced allergic symptoms after HPV vaccination or for women who are pregnant or planning to become pregnant. If an unintended pregnancy occurs after receiving an HPV vaccine, the vaccination should be held until the after giving birth, and termination of pregnancy is not recommended as no severe harm to the fetus has been noted.

Possible side effects and vaccine response after injection

• After vaccination, please take a rest under observation for 30 minutes. If there is no discomfort, you may leave the hospital.
• Common adverse reactions of HPV vaccination are mild fever, headache, dizziness and pain, swelling, itching at the injection site. Most reactions are mild to moderate and last for only a short time.

Reminders

• At present, HPV vaccines can prevent 60-90% of cervical cancer. More than 90% of genital warts can be prevented by vaccination with 4-valent or 9-valent vaccines, but even with vaccination, safe sex should still be practiced and regular pap tests should be received each year at least after the age of 30.
• Vaccination schedule and gender:
• 9-valent vaccine Gardasil (HPV types 6, 11, 16, 18, 31, 33, 45, 52, 58): 0, 2, 6 months (for 15~45 years old female and male); 0, 6 months (for 9~14 years old female and male).
• Tetravalent vaccine Gardasil (HPV types 6, 11, 16, 18): 0, 2, 6 months (for 14~45 years old female and 9~26 years old male); 0, 6 months (for 9~13 years old female).
• Bivalent vaccine Cervarix (HPV types 16, 18): 0, 1, 6 months (for above 15 years old female); 0, 6 months (for 9~14 years old female).