A modelled analysis of the impact of COVID-19-related disruptions to HPV vaccination analysis

COVID-19 disrupted school attendance in many countries, delaying routine adolescent vaccination against human papillomavirus (HPV) in some settings. We used the ‘Policy1-Cervix’HPV model (natural history/vaccination/screening/HPV-related cancers), to estimate the impact on HPV-related cancers from disruptions to HPV vaccination in a high-income setting. Compared to no disruption (nonavalent vaccine uptake, age 12 [females:82.4%; males:75.5%] as in Australia), additional lifetime HPV-related cancer cases were calculated for three disruption scenarios affecting one birth cohort (2008): i) 1-year delay (no doses missed); ii) 1 to 7-year delay (slow catch-up); iii) no catch-up (herd effects only). A fourth scenario assumed no catch-up for two cohorts (2008,2009). We found a 1-year delay could result in ≤0.3% more HPV-related cancers (n=4) but the increase would be greater if catch-up was slower (5%; n=70), and especially if there was no catch-up (49%; n=750). Additional cancers for a single missed cohort were most commonly cervical (23%), oropharyngeal (males:20%) or anal (females:16%). In the worst-case scenario of two cohorts missing vaccination, ≤62% more HPV-related cancers would be diagnosed (n=1,892). In conclusion, providing catch-up of missed HPV vaccines is conducted, short-term delays in vaccinating adolescents are unlikely to have substantial long-term effects on cancer.