Decision-making considerations for single-dose HPV vaccination, including drivers of schedule adoption or switch: insights from immunisation stakeholders in 19 low-income and middle-income countries.

introductionEmerging evidence of durable immunogenicity from mono-dose human papillomavirus vaccination (HPVV) prompted the WHO to recommend a single-dose HPVV schedule in December 2022. There is, however, limited understanding of processes and considerations influencing country adoption of the updated HPVV dosing schedule recommendation.

methodsWe identified four archetypes characterising countries' progress along the HPVV introduction and single-dose adoption continua. From September 2023 to February 2024, we purposefully sampled and conducted semistructured interviews with immunisation stakeholders representing Ministries of Health, Gavi-funded technical assistance partners, civil society organisations and multilateral agencies from African and Asian low-income and middle-income countries. Using multicycle, iterative thematic analysis, we identified factors enabling the adoption of the HPVV single-dose recommendation, as well as constraints to rendering a decision on the HPVV dosing schedule.

resultsWe interviewed 66 stakeholders across 19 countries with mature HPVV programmes (n=11) or forthcoming national HPVV introductions (n=8), as well as countries adopting (n=10) or undecided about (n=9) the single-dose schedule. Stakeholders conveyed enthusiasm for single-dose HPVV, citing the following anticipated benefits: higher HPVV schedule completion and coverage, especially in underimmunised populations; costs saved from operational reconfigurations and reduced vaccine procurement demands, particularly for countries transitioning out of Gavi co-financing in a vaccine supply-constrained environment; and optimised vaccine stock management capacity, importantly for countries pursuing new vaccine introductions for multiple antigens simultaneously. Factors demotivating HPVV single-dose schedule adoption or delaying decision-making included: limited localised evidence of long-term immunologic protection from single-dose HPVV; off-label product use liabilities; costs/resources required for retraining the health workforce in countries with mature HPVV programmes; and potential for widening HPVV coverage inequities, notably in countries with elevated HIV burdens.

conclusionsCoupled with the WHO's endorsement, the perceived benefits of single-dose HPVV consistently outweighed the anticipated risks, even when these risks delayed country-level HPVV schedule-related decision-making.