Vaccinating boys may be an appealing complementary strategy for the prevention of HPV-related diseases and has been introduced in a few countries already. It is important to understand the impact of vaccinating boys on tumor-site specific cancers and pre-cancers. A key parameter when assessing the impact is the herd immunity effect from a girls’ only program.
We developed a Bayesian synthesis framework to account for all vaccine type-related cancers and herd immunity effects from vaccinating girls and boys. The model has been calibrated to six countries from different regions in Europe. For this presentation, we evaluated the impact of vaccinating boys on oropharyngeal cancers in males and females.
Vaccinating 40% of boys in six European countries prevents 687 cancer cases per 100,000 women and 445 cancer cases per 100,000 men. Of those, 278 cancer cases per 100,000 individuals are prevented in the oropharyngeal region, with 95% of the gain attributed to men. Vaccinating 40% of boys prevents 25% of all HPV-related oropharyngeal cancers.
Vaccinating boys is expected to contribute substantially to a decrease in the occurrence of oropharyngeal cancers.