Journal Article

Switching from a 2-dose to a 1-dose program of gender-neutral routine vaccination against human papillomavirus in Canada: a mathematical modelling analysis

Ogilvie, Gina, MD DrPH, Brisson, Marc, PhD, Laprise, Jean-François, PhD, Chamberland, Éléonore, MSc, Wilson, Sarah, MD MSc, Drolet, Mélanie, PhD, Lim, Gillian H., MSc, Tuite, Ashleigh, PhD MPH, Sauvageau, Chantal, MD MSc

2024

Overview

ABSTRACTBackgroundWorldwide, countries are examining whether to implement 1-dose human papillomavirus (HPV) vaccination instead of using 2 doses. To inform policy, we sought to project the population-level impact and efficiency of switching from 2-dose to 1-dose gender-neutral routine HPV vaccination in Canada. MethodsWe used HPV-ADVISE, an individual-based transmission-dynamic model of HPV infections and diseases, to mathematically model vaccination programs in 2 provinces, Quebec, a province with high HPV vaccination coverage (around 85%), and Ontario, which has lower coverage (around 65%). We examined non-inferior and pessimistic scenarios of the efficacy (vaccine efficacy of 98% or 90%) and average vaccine duration (lifelong, 30 yr, or 25 yr) of 1 dose compared with 2 doses (98% vaccine efficacy, lifelong vaccine duration). Our main outcomes were the relative reduction in HPV-16 (by sex) and cervical cancers, and the number of doses needed to prevent 1 cervical cancer. ResultsOur model projected that 1-dose HPV vaccination would avert a similar number of cervical cancers as 2 doses in Canada, under various scenarios. Under the most pessimistic scenario (25-yr vaccine duration), 1-dose vaccination would avert fewer cervical cancers than 2 doses, by about 3 percentage points over 100 years. All 1-dose scenarios were projected to lead to elimination of cervical cancer (< 4 cervical cancers/100 000 female-years) and to be a substantially more efficient use of vaccine doses than a 2-dose scenario (1-dose v. no vaccination = 800–1000 doses needed to prevent 1 cervical cancer; incremental doses for 2-dose v. 1-dose vaccination > 10 000 doses needed to prevent 1 additional cervical cancer). InterpretationIf the average duration of 1-dose protection is longer than 25 years, a 1-dose HPV vaccination program would protect those vaccinated during their peak ages of sexual activity and prevent a similar number of HPV-related cancers as a 2-dose program, while being a more efficient use of vaccine doses.

• Publisher: CMA Impact Inc,CMA Impact, Inc
• Subject: Adolescent / Adult / Canada - epidemiology / Cancer / Cervical cancer / Child / Efficiency / Epidemiology / Female / Females / Gender / Human papillomavirus / Human Papillomavirus Viruses / Humans / Immunization / Immunization Programs / Immunization Schedule / Industrialized nations / Infection / Internal Medicine / Low income groups / Male / Mathematical models / Medical screening / Models, Theoretical / Ontario - epidemiology / Papillomavirus Infections - prevention & control / Papillomavirus Vaccines - administration & dosage / Papillomaviruses / Prevention / Provinces / Quebec - epidemiology / Uterine Cervical Neoplasms - prevention & control / Uterine Cervical Neoplasms - virology / Vaccination / Vaccination - statistics & numerical data / Vaccines / Young Adult