Background Of late, there has been discussion around the potential for vaccinating males in addition to the routine female human papillomavirus (HPV) vaccination programme against cervical cancer. While men who have sex with women (MSW) will likely receive some protection from female vaccination, men who have sex with men (MSM) remain vulnerable. Incidence rates of vaccine preventable cancers are disproportionately represented among MSM.
Methods Based on the natural history of infection progression for HPV subtypes 6, 11, 16 and 18, mathematical transmission dynamics and cost-effectiveness analysis models were developed to assess the prevalence and incidence of these subtypes among the MSM population in the Greater Vancouver Area, British Columbia, Canada. Model parameters, demographic, and epidemiological data were informed from provincial data and the literature.
We simulated three additional vaccination strategies, in combination with the current programme (Grade 6 schoolgirls (with 70% vaccine coverage)): first, vaccination of Grade 6 boys (with 70% vaccine coverage); second, vaccinating 18-year old self-identified MSM (with 25, 50 or 75% vaccine coverage); and finally, vaccinating any MSM within the vaccine-approved age range (with 25, 50 or 75% vaccine coverage).
Results There is significant variability of cost estimates associated with clinical outcomes related to the HPV vaccine-preventable strains in the literature. Our sensitivity analysis indicates that the implementation of any scenario tested is incrementally cost effective, assuming a baseline of the current girls-only immunisation programme. On average, overall incidence of anal, penile, and oropharyngeal cancer cases attributable to vaccine-preventable strains will be reduced by approximately 90%, within 50 years, and given effective prophylaxis and lifelong immunity.
Conclusion All targeted MSM immunisation scenarios tested were cost-effective by averting high costs related to each cancer case avoided and given the relatively low number of vaccine doses required within this population, compared to the male population at large.
- Cost Effectiveness
- Human Papilloma Virus vaccine
- men who have sex with men