Ismail S, Deeks S
Public Health Agency of Canada, Centre for Immunization and Respiratory Infectious Diseases, Ottawa, ON.
NACI HPV Working Group Chair, Toronto, ON.
Can Commun Dis Rep. 2015 Apr 20;41(Suppl 3):11-13. doi: 10.14745/ccdr.v41is3a03.
Human papillomavirus (HPV) infections are the most common sexually transmitted infections. In the absence of vaccination, it is estimated that 75% of sexually active Canadians will have a sexually transmitted HPV infection at some point in their lives. Canada's National Advisory Committee on Immunization (NACI) has recommended a three-dose immunization schedule with HPV vaccine for females 9 years of age and older and for males between 9 and 26 years of age, since 2007 and 2012, respectively.
To outline the evidence on a two-dose HPV vaccine schedule and to make recommendations for the optimal HPV immunization schedule in Canada.
NACI reviewed the evidence used by the World Health Organization's (WHO's) Strategic Advisory Group of Experts (SAGE) on Immunization for the two-dose HPV immunization schedule recommended for immunocompetent girls 9 to 14 years of age and conducted an additional review of literature for studies not included in, or published after, the SAGE review. A knowledge synthesis was performed then NACI approved specific recommendations and elucidated the rationale and relevant considerations.
Based on the evidence available to date, a two-dose HPV immunization schedule among immunocompetent 9- to 14-year-olds is expected to provide similar protective efficacy compared to a three-dose schedule in immunocompetent individuals aged 9 to 26 years. While all studies reviewed included only females, there is no reason to believe that the data would be different in males, given that data from three-dose trials demonstrates similar immune responses. Administration of two doses of HPV vaccine rather than three may increase acceptability by students, parents and health care professionals alike, and may lead to improved HPV immunization coverage and efficiencies by public health agencies. The duration of protection of either two doses or three doses of HPV vaccine is not yet known; research is encouraged to determine whether there is need for a booster dose.
Based on the evidence available to date, a two-dose HPV immunization schedule (given at least six months apart) among immunocompetent 9- to 14-year-olds may be considered by individuals and jurisdictions to allow for potential cost savings and other individual and programmatic advantages. A three-dose schedule should be used in individuals 15 years of age and older, as well as immunocompromised individuals and immunocompetent HIV-infected individuals. The new and complete set of current recommendations for HPV vaccines will be published in the updated HPV chapter in the in the near future.
人乳头瘤病毒（HPV）感染是最常见的性传播感染。据估计，在未接种疫苗的情况下，75% 性活跃的加拿大人在其生命中的某个阶段会感染性传播的HPV。自2007年和2012年起，加拿大国家免疫咨询委员会（NACI）分别建议对9岁及以上女性和9至26岁男性采用三剂HPV疫苗免疫接种计划。
概述关于两剂HPV疫苗接种计划的证据，并为加拿大最佳HPV免疫接种计划提出建议。
NACI审查了世界卫生组织（WHO）免疫战略咨询专家组（SAGE）用于为9至14岁免疫功能正常女孩推荐的两剂HPV免疫接种计划的证据，并对SAGE审查中未纳入或之后发表的研究进行了额外的文献综述。进行了知识综合，然后NACI批准了具体建议并阐明了理由和相关考虑因素。
根据目前可得的证据，对于9至14岁免疫功能正常的人群，两剂HPV免疫接种计划预计与9至26岁免疫功能正常人群的三剂接种计划具有相似的保护效力。虽然所有审查的研究仅纳入了女性，但鉴于三剂试验的数据显示出相似的免疫反应，没有理由认为男性的数据会有所不同。接种两剂HPV疫苗而非三剂可能会提高学生、家长和医疗保健专业人员的接受度，并可能导致公共卫生机构提高HPV免疫接种覆盖率和效率。两剂或三剂HPV疫苗的保护持续时间尚不清楚；鼓励开展研究以确定是否需要加强剂量。
根据目前可得的证据，个人和司法管辖区可考虑对9至14岁免疫功能正常的人群采用两剂HPV免疫接种计划（至少间隔六个月），以实现潜在的成本节约以及其他个人和计划方面的优势。15岁及以上人群、免疫功能低下个体以及免疫功能正常的HIV感染者应采用三剂接种计划。最新的HPV疫苗完整建议将在近期更新的《加拿大免疫指南》HPV章节中发布。
