Non-restrictive open vial policy combined with the home visit vaccinations for improving BCG coverage in a high-incidence outreach region: A model-based cost-effectiveness analysis for Indonesia

Abstract

Bacillus Calmette-Guérin (BCG) vaccination is recommended at birth or in the first week of life to achieve the most beneficial effects in protecting against the most severe type of tuberculosis (TB) disease in children. However, delayed vaccination is commonly reported, especially in outreach or rural areas. We assessed the cost-effectiveness of combining non-restrictive open vial and home visit vaccination strategies in order to increase timely BCG vaccination in a high-incidence outreach setting. We applied a simplified Markov model for the Papua setting, which resembled a high-incidence outreach setting in Indonesia, to assess the cost-effectiveness of these strategies from a health care and a societal perspective. A moderate increase (75% wastage rate and 25% home vaccination) and a large increase (95% wastage rate and 75% home vaccination) scenario were assessed in the analysis. We calculated incremental cost-effectiveness ratios (ICER) based on the incremental costs and quality-adjusted life years (QALYs) gained by comparing the two strategies to the base case scenario (35% wastage rate and no home vaccination). The costs per vaccinated child were US$10.25 in the base case scenario, increasing slightly in the moderate (US$10.54) and large increase scenarios (US$12.38). The moderate increase scenario was predicted to prevent 5783 TB-related deaths and 790 TB cases while the large increase scenario predicted the prevention of 9865 TB-related deaths and 1348 TB cases for the entire lifespan of our cohort. From a health care perspective, the ICERs were predicted to be US$288/QALY and US$487/QALY, respectively, for the moderate and large increase scenarios. Using Indonesia's gross domestic product (GDP) per person as a threshold, both strategies were considered to be cost-effective. We found that the allocation of resources for timely BCG vaccination based on combining home vaccination and a less restrictive open vial strategy could substantially reduce childhood TB cases and TB-related mortality. Although outreach activities are more expensive than vaccination at a health care facility only, these activities proved to be cost-effective. These strategies might also be beneficial in other high-incidence outreach settings.