Investment in vaccine product development should be guided by up-to-date and transparent global burden of disease estimates, which are also fundamental to policy recommendation and vaccine introduction decisions. For low- and middle-income countries (LMICs), vaccine prioritization is primarily driven by the number of deaths caused by different pathogens. Enteric diseases are known to be a major cause of death in LMICs. The two main modelling groups providing mortality estimates for enteric diseases are the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, Seattle and the Maternal Child Epidemiology Estimation (MCEE) group, led by Johns Hopkins Bloomberg School of Public Health. Whilst previous global diarrhoea mortality estimates for under five-year-olds from these two groups were closely aligned, more recent estimates for 2016 have diverged, particularly with respect to numbers of deaths attributable to different enteric pathogens. This has impacted prioritization and investment decisions for vaccines in the development pipeline.

The mission of the Product Development for Vaccines Advisory Committee (PDVAC) at the World Health Organisation (WHO) is to accelerate product development of vaccines and technologies that are urgently needed and ensure they are appropriately targeted for use in LMICs. At their 2018 meeting, PDVAC recommended the formation of an independent working group of subject matter experts to explore the reasons for the difference between the IHME and MCEE estimates, and to assess the respective strengths and limitations of the estimation approaches adopted, including a review of the data on which the estimates are based.

Here, we report on the proceedings and recommendations from a consultation with the working group of experts, the IHME and MCEE modelling groups, and other key stakeholders. We briefly review the methodological approaches of both groups and provide a series of proposals for investigating the drivers for the differences in enteric disease burden estimates.

疫苗产品开发的投资应以最新和透明的全球疾病负担估算为指导，这也是政策建议和疫苗引进决策的基础。对于中低收入国家（LMIC），疫苗优先排序主要由不同病原体导致的死亡人数决定。众所周知，肠道疾病是LMIC的主要死因。提供肠道疾病死亡率估算的两个主要模型组是华盛顿大学西雅图市卫生计量与评估研究所（IHME）和约翰霍普金斯大学彭博公共卫生学院领导的母婴流行病学估计（MCEE）组。虽然先前对这两组的5岁以下儿童的全球腹泻死亡率估计值是紧密一致的，2016年的最新估计数存在差异，尤其是在归因于不同肠道病原体的死亡人数方面。这影响了开发流程中疫苗的优先次序和投资决策。

世界卫生组织（WHO）的疫苗产品开发咨询委员会（PDVAC）的任务是加快急需的疫苗和技术的产品开发，并确保将其适当地用于LMIC。在其2018年会议上，PDVAC建议成立一个由主题专家组成的独立工作组，以探讨IHME和MCEE估算之间差异的原因，并评估所采用估算方法的各自优势和局限性，包括对估计所依据的数据。

在这里，我们通过与专家工作组，IHME和MCEE建模组以及其他主要利益相关者进行磋商的方式，汇报会议记录和建议。我们简要回顾了两组的方法论方法，并提供了一系列建议，以调查造成肠道疾病负担估算差异的驱动因素。