A long-term follow-up programme, HPVnorvaks, was established when the vaccine was introduced. The programme includes ongoing monitoring and reporting of immunisation coverage, as well as undesirable events. In addition, the monitoring programme includes a number of projects aimed to study the efficacy of the vaccine on the prevalence of HPV infection, on the pre-cancerous stages of cervical cancer and on cervical cancer.
Study of HPV prevalence in young women
During 2011, approximately 25 000 Norwegian girls born in 1994 were invited to participate in a survey to determine the prevalence of HPV in young women. So far, more than 6,000 have agreed to participate. Participants sent a urine sample to the Norwegian Institute of Public Health which was then analysed at the HPV reference laboratory at Akershus University Hospital. From January 2012, a nationwide sample of 21-year-old women will also be invited to participate in the study.
All medicines, including vaccines, can have unwanted effects. The HPV vaccine Gardasil is used in the Childhood Immunisation Programme. The vaccine was well tested before approval and more than 74 million doses have been distributed worldwide. Reported side effects so far are as expected and give no reason to change current recommendations about the use of the vaccine. In general, there are reports of short-term discomfort associated with vaccination. Since introduction of the vaccine in the Norwegian Childhood Immunisation Programme, 316 suspected adverse events, including 19 serious events were reported by 16th December 2011.
The vast majority of reported events were benign and transient reactions at the injection site. Some people reported pain and tenderness in the arm; some became nauseous, vomited or had abdominal pain. In the 19 reported serious events, the girls were admitted to hospital because of their reactions (fainting, seizures or allergies), but are now recovered or in recovery.