Frequently Asked Questions
1. Is there a vaccine to help to prevent HPV?
Yes, two HPV vaccines are available in South Africa. These vaccines prevent 2 types of HPV (HPV16 and 18) that causes up to 70 % of all cervical cancers. One of the vaccines also protects against the 2 types of HPV (HPV6 and 11) that cause up to 90 % of all genital warts.18, 22
2. Why should I vaccinate against HPV-related diseases?
Large-scale vaccination programmes have proven to be highly effective in controlling the morbidity and mortality associated with diseases such as poliomyelitis, smallpox, diphtheria, tetanus, yellow fever, pertussis, Haemophilus influenzae, Haemophilus influenza related diseases, measles, mumps, and rubella. Given the various clinical manifestations associated with HPV infection, vaccination will have the potential to reduce the incidence of HPV-related diseases associated with significant morbidity and mortality throughout the world.23
While large-scale pap smear screening has been effective in dramatically reducing the rates of cervical cancer in developed countries, it still remains the fourth most common cancer in women residing in these regions. Moreover, in developing countries, where many women do not have access to screening programmes, cervical cancer is the second most commonly diagnosed cancer, and the leading cause of cancer-related mortality. Thus, prevention of HPV infection could serve as an adjunct to screening programmes and may result in cost savings if it decreases the prevalence of abnormal pap smear results, genital warts, and cervical cancer morbidity and mortality.23
3. What are the known side effects of the HPV vaccines?
The most common side effects from HPV vaccines are:
- pain, redness, swelling at injection site
- muscle, joint pain 24, 35
4. What is an adverse event?
An adverse event is a health problem that occurs after someone receives a vaccine or medicine. It may or may not have been caused by the vaccine or medicine. For example, the person might get a headache after getting a vaccine. This might be caused by the vaccine or it might be caused by something else.24, 35
5. Who is in charge of monitoring the safety of vaccines?
In South Africa, the Medicines Control Council (MCC) monitors safety by reviewing local adverse events reports and liaising with international agencies. In the United States two government agencies, the Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC), monitor the safety of vaccines. It is the responsibility of the pharmaceutical companies to continuously monitor the safety of vaccines pre- and post- registration.24, 35
6. How is the safety of vaccines monitored after they are licensed?
- In South Africa, any adverse event must be reported to either the MCC or the manufacturing pharmaceutical company.24, 35
- In pre-licensure trials, no serious adverse events attributable to the vaccine were recorded for either the quadrivalent or bivalent HPV vaccine.34
In the USA, there are 3 systems used to monitor the safety of vaccines after they are licensed and being used. These systems can monitor side effects already known to be caused by vaccines as well as detect rare adverse events that were not identified during a vaccine's clinical trials.24, 35
7. What types of adverse events have been reported?
The majority of reported adverse events worldwide following HPV vaccination have been considered mild. Reports have included pain and swelling at the injection site, fever, dizziness, and nausea. Reports of people fainting have also been received.Fainting is common after injections, especially in pre-teens and teens. Falls that occur after someone faints can cause serious injuries, such as head injuries. To help prevent injuries both package inserts of the HPV vaccines recommend sitting or lying down for 15 minutes after vaccination.24, 35
8. Will vaccination eliminate the need to for pap smears?
HPV vaccination will offer protection against the high-risk HPV types responsible for most cases of cervical cancer. However, at least 13 other genotypes are responsible for approximately 30 % of cervical cancer. Additionally, vaccination may not be 100 % effective against the common high-risk types 16 and 18 and immunity may decline. Finally, some women will have already been infected with one or more vaccine types prior to vaccination. In these cases, the vaccine will not be efficacious in altering the natural history of these established infections, and some may go on to develop into precancers and cancers. Thus, it is important to ensure that women of all ages must continue to receive regular pap smears even after vaccination.2, 15, 23, 34
9. Can women who are already infected with HPV benefit from the quadrivalent vaccine?
Yes. In women who were positive to one or more HPV types covered by the vaccine (HPV 6, 11, 16, or 18) at enrollment into clinical trials, the quadrivalent vaccine provided protection against disease related to the remaining types (i.e. protection against the type to which they were naïve). In other words, a subject who was infected with HPV type 6 prior to vaccination still received protection from disease caused by HPV 11, 16 and/or 18. A recent study showed significant reductions in the recurrences of subsequent HPV diseases for vaccinated individuals.25