Emerging Pathogens Institute, Food Systems Institute, Animal Sciences Department, University of Florida, Gainesville, Florida, United States of America.
Delft Institute of Applied Mathematics, Delft University of Technology, Delft, The Netherlands.
PLoS Negl Trop Dis. 2022 Sep 12;16(9):e0010663. doi: 10.1371/journal.pntd.0010663. eCollection 2022 Sep.
According to the World Health Organization, 600 million cases of foodborne disease occurred in 2010. To inform risk management strategies aimed at reducing this burden, attribution to specific foods is necessary.
We present attribution estimates for foodborne pathogens (Campylobacter spp., enterotoxigenic Escherichia coli (ETEC), Shiga-toxin producing E. coli, nontyphoidal Salmonella enterica, Cryptosporidium spp., Brucella spp., and Mycobacterium bovis) in three African countries (Burkina Faso, Ethiopia, Rwanda) to support risk assessment and cost-benefit analysis in three projects aimed at increasing safety of beef, dairy, poultry meat and vegetables in these countries.
We used the same methodology as the World Health Organization, i.e., Structured Expert Judgment according to Cooke's Classical Model, using three different panels for the three countries. Experts were interviewed remotely and completed calibration questions during the interview without access to any resources. They then completed target questions after the interview, using resources as considered necessary. Expert data were validated using two objective measures, calibration score or statistical accuracy, and information score. Performance-based weights were derived from the two measures to aggregate experts' distributions into a so-called decision maker. The analysis was made using Excalibur software, and resulting distributions were normalized using Monte Carlo simulation.
Individual experts' uncertainty assessments resulted in modest statistical accuracy and high information scores, suggesting overconfident assessments. Nevertheless, the optimized item-weighted decision maker was statistically accurate and informative. While there is no evidence that animal pathogenic ETEC strains are infectious to humans, a sizeable proportion of ETEC illness was attributed to animal source foods as experts considered contamination of food products by infected food handlers can occur at any step in the food chain. For all pathogens, a major share of the burden was attributed to food groups of interest. Within food groups, the highest attribution was to products consumed raw, but processed products were also considered important sources of infection.
Cooke's Classical Model with performance-based weighting provided robust uncertainty estimates of the attribution of foodborne disease in three African countries. Attribution estimates will be combined with country-level estimates of the burden of foodborne disease to inform decision making by national authorities.
根据世界卫生组织的数据，2010 年发生了 6 亿例食源性疾病。为了制定旨在减轻这一负担的风险管理策略，有必要确定具体的食物来源。
我们提供了三个非洲国家（布基纳法索、埃塞俄比亚和卢旺达）食源性病原体（弯曲菌、肠产毒性大肠杆菌（ETEC）、产志贺毒素大肠埃希氏菌、非伤寒沙门氏菌、隐孢子虫、布鲁氏菌和牛分枝杆菌）的归因估计，以支持这三个国家旨在提高牛肉、奶制品、禽肉和蔬菜安全性的三个项目的风险评估和成本效益分析。
我们使用与世界卫生组织相同的方法，即根据 Cooke 的经典模型进行结构化专家判断，为这三个国家使用三个不同的专家组。专家通过远程访谈进行采访，并在采访过程中完成校准问题，而无需访问任何资源。然后，他们在采访后使用认为必要的资源完成目标问题。使用两种客观衡量标准，校准分数或统计准确性和信息分数，对专家数据进行验证。基于绩效的权重是从这两个衡量标准中得出的，用于将专家的分布汇总到所谓的决策者中。使用 Excalibur 软件进行分析，并使用蒙特卡罗模拟对生成的分布进行归一化。
个别专家的不确定性评估导致统计准确性适中且信息得分较高，表明评估过于自信。尽管如此，经过优化的项目加权决策者在统计上是准确和有信息的。虽然没有证据表明动物致病性 ETEC 菌株对人类具有传染性，但由于专家认为受感染的食品处理人员可能在食物链的任何环节污染食品产品，因此相当一部分 ETEC 疾病归因于动物源食品。对于所有病原体，很大一部分负担归因于感兴趣的食物组。在食物组内，归因于生食用的产品最高，但加工产品也被认为是重要的感染源。
基于绩效的加权 Cooke 经典模型为三个非洲国家食源性疾病的归因提供了稳健的不确定性估计。归因估计将与国家层面的食源性疾病负担估计相结合，为国家当局的决策提供信息。
