Human Papillomavirus Vaccine
1. How common is cervical cancer?
Cervical cancer is 2nd most common cancer seen in lndian women. As per Globocan 2020 data, every year in lndia, 123,907 new cases are diagnosed and 77,348 women die due to this cancer.43
2. What causes cervical cancer?
Cervical cancer is caused by the Human Papillomavirus (HPV). There are about 100 known types of HPV. These are classified as high risk and low risk. High risk HPV types have been linked to cervical cancer. Low risk HPV types, such as HPV 6 and 11 are not known to cause cancer but are responsible for genital warts.44
3. Will vaccinating as early as 10 years of age protect women from cervical cancer in the future? How long does vaccine protection last?
- Antibodies are an important co-relate of long-term protection. lt is believed that antibody levels that are
consistently high over a period of time and are likely to stay high, would provide long term protection against
cervical cancer45 - With Cervarix (GSK HPV vaccine), mathematical modelling suggests that these antibodies are likely to persist for
at least 50 years45 - Hence, vaccination started at 10 years would confer protection against cervical cancer in thefuture45,46
4. Should we be vaccinating boys/men as well to reduce overall incidence since they act as reservoirs for re-infection?
- As per WHO Position paper 2017, Gender-neutral vaccination is always less cost-effective than vaccination of girls only47
5. What are availalble scheules for HPV vaccines?
Age at the time of the first injection | Immunization and schedule47 |
---|---|
9 years to and including 14 years | Two doses each of 0.5 ml. The second dose should be given between 5 and 13 months after the first dose |
Two doses each of 0.5 ml. The second dose should be given between 5 and 13 months after the first dose | Three doses each of 0.5 ml each at 0,1-2,6 months |
6. What is the flexibility in vaccination schedule available with Cervarix46
- 2 vaccine dose schedule: lf the second vaccine dose is administered before the 5th month after the first dose, a third dose should always be administered. The 2nd dose should be given between 5 and 13 months after the first dose
- 3 vaccine dose schedule: lf flexibility In the vaccination schedule is necessary, the second dose can be administered between 1 month and 2.5 months after the first dose and the third dose between 5 and 12 months after the first dose
7. Is screening necessary for sexually active women before vaccination?
- Screening women prior to vaccination is not a necessary prerequisite. Even if a woman is currently infected with an oncogenic HPV type, she will still stand to benefit from vaccination against new infections with the same or different HPV type(s).48
8. Is Cervarix safe to use in pregnant/lactating women?
- Specific studies of the vaccine in pregnant women were not conducted. Cervarix is not to be used during pregnancy. Women who are pregnant or trying to become pregnant, are advised to postpone or interrupt vaccination until completion of pregnancy
- The effect on breast-fed infants of the administration of Cervarix to their mgthers has not been evaluated. Cervarix is not to be used during lactation
9. What is efficacy of Cervarix?46
- ln large studies where efficacy is measured up to CIN3+; Cervarix has demonstrated 100% efficacy against HPV 16 and 18
- ln HPV Naive population, Cervarix has demonstrated 93% efficacy irrespective of HPV types
- lt is more reassuring to know that in Sexually active young women, Cervarix efficacy is 66% irrespective of HPV types60
10. Cervarix safety information33
- Cervarix safety information33
- very common: Headache, myalgia, injection site reactions including pain, redness, swelling; fatigue
- common: Gastrointestinal symptoms including nausea, vomiting, diarrhoea and abdominal pain, itching/pruritus, rash, urticaria, arthralgia, fever (38.C)