Department of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
Vaccine. 2013 Oct 1;31(42):4848-55. doi: 10.1016/j.vaccine.2013.07.073. Epub 2013 Aug 9.
Gardasil, a human papillomavirus (HPV) vaccine, began among grade 6 girls in Manitoba, Canada in 2008. In Manitoba, there is evidence that First Nations, Métis, and Inuit women (FNMI) have higher HPV prevalence, lower invasive cervical cancer (ICC) screening, and higher ICC incidence than all other Manitoban (AOM) women. We developed a mathematical model to assess the plausible impact of unequal vaccination coverage among school girls on future cervical cancer incidence.
We fit model estimated HPV prevalence and ICC incidence to corresponding empirical estimates. We used the fitted model to evaluate the impact of varying levels of vaccination uptake by FNMI status on future ICC incidence, assuming cervical screening uptake among FNMI and AOM women remained unchanged.
Depending on vaccination coverage, estimated ICC incidence by 2059 ranged from 15% to 68% lower than if there were no vaccination. The level of cross-ethnic sexual mixing influenced the impact that vaccination rates among FNMI has on ICC incidence among AOM, and vice versa. The same level of AOM vaccination could result in ICC incidence that differs by up to 10%, depending on the level of FNMI vaccination. Similarly, the same level of FNMI vaccination could result in ICC incidence that differs by almost 40%, depending on the level of AOM vaccination.
If we are unable to equalize vaccination uptake among all school girls, policy makers should prepare for higher levels of cervical cancer than would occur under equal vaccination uptake.
Gardasil 是人乳头瘤病毒（HPV）疫苗，于 2008 年在加拿大马尼托巴省开始为六年级女生接种。在马尼托巴省，有证据表明，第一民族、梅蒂斯和因纽特妇女（FNMI）的 HPV 感染率较高，侵袭性宫颈癌（ICC）筛查率较低，ICC 发病率高于所有其他马尼托巴省（AOM）妇女。我们开发了一个数学模型来评估在校女生 HPV 疫苗接种率不均等对未来宫颈癌发病率的潜在影响。
我们将 HPV 感染率和 ICC 发病率的模型估计值与相应的经验估计值拟合。我们使用拟合模型来评估不同 FNMI 疫苗接种率对未来 ICC 发病率的影响，假设 FNMI 和 AOM 妇女的宫颈筛查接种率保持不变。
根据疫苗接种覆盖率的不同，到 2059 年，估计的 ICC 发病率比没有疫苗接种的情况下低 15%至 68%。跨族裔性混合的程度影响了 FNMI 中的疫苗接种率对 AOM 中的 ICC 发病率的影响，反之亦然。相同水平的 AOM 疫苗接种可能导致 ICC 发病率相差 10%，具体取决于 FNMI 疫苗接种水平。同样，FNMI 疫苗接种水平相同可能导致 ICC 发病率相差近 40%，具体取决于 AOM 疫苗接种水平。
如果我们不能使所有女校女生的疫苗接种率均等化，决策者应该为更高水平的宫颈癌做好准备，而不是在均等的疫苗接种率下出现的情况。
