Human papillomavirus (HPV) is one of the most common sexually transmitted infections.
Oncogenic, high risk HPV types 16 and 18 are associated with approximately 70% of all cervical cancers. Oncogenic HPV types 31, 33, 35, 45, 52 and 58 account for an additional 20% of cervical cancers. Infection with oncogenic HPV types is also associated with cancers of the anus, oropharynx, penis, vagina and vulva.
Non-oncogenic, low risk HPV types 6 and 11 are responsible for 90% of anogenital warts.
In 2010, two HPV vaccines were licensed for use in Canada, CervarixTM (GlaxoSmithKline) and Gardasil® (Merck). While both vaccines provide protection against HPV types 16 and 18, Gardasil also protects against HPV types 6 and 11.
Clinical trials have demonstrated both HPV vaccines to be highly efficacious (95% – 100% vaccine efficacy) against precancerous cervical lesions. However, the vaccines’ long-term protectiveness is unknown at this time.
The majority of HPV vaccine associated adverse events reported in Canada have been pain at the injection site.
All provinces and territories in Canada have implemented publicly-funded HPV vaccination programs. However, reported HPV vaccine uptake varies across the country, ranging from around 50% in Alberta and Manitoba to approximately 85% in Newfoundland, Nova Scotia and Quebec.
Although the HPV vaccine has the potential to play a significant role in reducing the incidence of cervical cancer, the HPV vaccine is type specific for only 70% of cervical cancers and not all girls will receive the vaccine, thus resources to maintain the availability and access to Pap tests must remain.
Extension of the public HPV vaccination program to males was under consideration [at the time of publication] in the provinces of Prince Edward Island, New Brunswick, and Quebec.