Bacillus Calmette-Guerin (BCG) vaccination: a global analysis of cost-effectiveness and optimal safety stock

BackgroundBacille Calmette-Guerin (BCG) is the most commonly-used vaccination globally, but multi-country cost-effectiveness analyses are outdated and have not considered sequelae in tuberculosis survivors. A rationale is lacking to guide the size of safety stocks. MethodsFor the 110 countries using universal neonatal BCG vaccination, we used a decision tree model to compare the costs and health benefits of status-quo BCG vaccination for children aged 0-4 years in 2023 to a counterfactual where no BCG was used, accounting for post-tuberculosis sequelae. We assessed cost-effectiveness against a threshold of 30% per capita gross domestic product from a health system perspective. We determined the safety stock that maximized expected net benefit. FindingsBCG vaccination prevented 742,000 (95% uncertainty interval[UI]: 541,000 to 991,000) tuberculosis episodes and 192,000 (95%UI:138,000 to 264,000) tuberculosis deaths globally. Of these, 49,000 (95%UI: 32,300 to 72,100) episodes and 30,000 (95%UI: 19,600 to 45,100) deaths prevented were from tuberculous meningitis. Universal neonatal BCG vaccination was cost-effective in the majority (75/110) of countries where it is used and in all countries with estimated tuberculosis incidence over 42 per 100,000 per year, with a median incremental cost-effectiveness ratio of $276 (interquartile range: $84 to $1514) per disability-adjusted life-year averted. Median optimal safety stock for a 10% uncertainty in demand was 11% (IQR: 7% to 17%) of expected demand. InterpretationBCG vaccination continues to prevent substantial morbidity and mortality in children globally, and cost-effectiveness considerations support continued universal vaccination in most countries with this policy currently. FundingUK EPSRC & DHSC