Related Experiment Video
Updated: Jun 11, 2025
Predicting the Effectiveness of Population Replacement Strategy Using Mathematical Modeling
Published on: July 4, 2007
Switching from a 2-dose to a 1-dose program of gender-neutral routine vaccination against human papillomavirus in
Mélanie Drolet1, Jean-François Laprise1, Éléonore Chamberland1
1Centre de recherche du CHU de Québec - Université Laval (Drolet, Laprise, Chamberland, Sauvageau, Brisson); Département de médecine sociale et préventive (Sauvageau, Brisson), Université Laval; Institut national de santé publique du Québec et Direction régionale de santé publique de la Capitale-Nationale (Sauvageau), Québec, Que.; Public Health Ontario (Wilson, Lim); Dalla Lana School of Public Health (Wilson, Tuite), University of Toronto, Toronto, Ont.; University of British Columbia (Ogilvie), Vancouver, BC; Centre for Immunization Programs (Tuite), Public Health Agency of Canada, Ottawa, Ont.
Background:
Worldwide, 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.
Methods:
We 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.
Results:
Our 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).
Interpretation:
If 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.
Related Concept Videos
01:23Mechanistic Models: Compartment Models in Individual and Population Analysis
01:51Vaccinations
01:23Types of Biopharmaceutical Studies: Controlled and Non-Controlled Approaches
Non-controlled studies, commonly employed for initial exploration, lack a control group, rendering them susceptible to biases and external influences. In contrast,...
01:30Cancer Vaccines
Cancer vaccines come in two categories: preventive (prophylactic) and treatment (active). Preventive vaccines, such as the Human Papillomavirus (HPV) vaccine, protect against viruses that cause certain...