Shaikh Nabila, Pelzer Puck T, Thysen Sanne M, Roy Partho, Harris Rebecca C, White Richard G
TB Modelling Group, TB Centre, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK.
Technical Division, KNCV Tuberculosis, Maanweg 174, 2516 AB The Hague, The Netherlands.
Vaccines (Basel). 2021 Oct 22;9(11):1228. doi: 10.3390/vaccines9111228.
The impact of COVID-19 disruptions on global Bacillus Calmette-Guérin (BCG) coverage and paediatric tuberculosis (TB) mortality is still unknown. To fill this evidence-gap and guide mitigation measures, we estimated the impact of COVID-19 disruptions on global BCG coverage and paediatric TB mortality. First, we used data from multiple sources to estimate COVID-19-disrupted BCG vaccination coverage. Second, using a static mathematical model, we estimated the number of additional paediatric TB deaths in the first 15 years of life due to delayed/missed vaccinations in 14 scenarios-varying in duration of disruption, and magnitude and timing of catch-up. We estimated a 25% reduction in global BCG coverage within the disruption period. The best-case scenario (3-month disruption, 100% catch-up within 3 months) resulted in an additional 886 (0.5%) paediatric TB deaths, and the worst-case scenario (6-month disruption with no catch-up) resulted in an additional 33,074 (17%) deaths. The magnitude of catch-up was found to be the most influential variable in minimising excess paediatric TB mortality. Our results show that ensuring catch-up vaccination of missed children is a critical priority, and delivery of BCG alongside other routine vaccines may be a feasible way to achieve catch-up. Urgent action is required to support countries with recovering vaccination coverages to minimise paediatric deaths.
2019冠状病毒病（COVID-19）疫情干扰对全球卡介苗（BCG）接种覆盖率及儿童结核病（TB）死亡率的影响仍不明确。为填补这一证据空白并指导缓解措施，我们估算了COVID-19疫情干扰对全球BCG接种覆盖率及儿童结核病死亡率的影响。首先，我们使用来自多个来源的数据估算受COVID-19干扰的BCG疫苗接种覆盖率。其次，我们使用一个静态数学模型，估算了在14种情景下，因疫苗接种延迟/漏种，在生命的前15年中额外增加的儿童结核病死亡人数，这些情景在干扰持续时间、补种规模和时间方面各不相同。我们估计在干扰期间全球BCG接种覆盖率下降了25%。最佳情景（3个月干扰，3个月内100%补种）导致额外886例（0.5%）儿童结核病死亡，而最差情景（6个月干扰且无补种）导致额外33,074例（17%）死亡。结果发现，补种规模是将儿童结核病额外死亡人数降至最低的最具影响力的变量。我们的结果表明，确保对漏种儿童进行补种是一项关键优先事项，同时接种BCG疫苗和其他常规疫苗可能是实现补种的一种可行方式。需要采取紧急行动，支持各国恢复疫苗接种覆盖率，以尽量减少儿童死亡。
