儿童志贺菌感染风险的时空变化：使用个体参与者数据的全球风险测绘和预测模型。

Spatiotemporal variation in risk of Shigella infection in childhood: a global risk mapping and prediction model using individual participant data.

机构信息

Department of Earth and Planetary Sciences, Johns Hopkins Krieger School of Arts and Sciences, Baltimore, MA, USA.

Division of Infectious Diseases and International Health, University of Virginia School of Medicine, Charlottesville, VA, USA.

出版信息

Lancet Glob Health. 2023 Mar;11(3):e373-e384. doi: 10.1016/S2214-109X(22)00549-6.

BACKGROUND

Diarrhoeal disease is a leading cause of childhood illness and death globally, and Shigella is a major aetiological contributor for which a vaccine might soon be available. The primary objective of this study was to model the spatiotemporal variation in paediatric Shigella infection and map its predicted prevalence across low-income and middle-income countries (LMICs).

METHODS

Individual participant data for Shigella positivity in stool samples were sourced from multiple LMIC-based studies of children aged 59 months or younger. Covariates included household-level and participant-level factors ascertained by study investigators and environmental and hydrometeorological variables extracted from various data products at georeferenced child locations. Multivariate models were fitted and prevalence predictions obtained by syndrome and age stratum.

FINDINGS

20 studies from 23 countries (including locations in Central America and South America, sub-Saharan Africa, and south and southeast Asia) contributed 66 563 sample results. Age, symptom status, and study design contributed most to model performance followed by temperature, wind speed, relative humidity, and soil moisture. Probability of Shigella infection exceeded 20% when both precipitation and soil moisture were above average and had a 43% peak in uncomplicated diarrhoea cases at 33°C temperatures, above which it decreased. Compared with unimproved sanitation, improved sanitation decreased the odds of Shigella infection by 19% (odds ratio [OR]=0·81 [95% CI 0·76-0·86]) and open defecation decreased them by 18% (OR=0·82 [0·76-0·88]).

INTERPRETATION

The distribution of Shigella is more sensitive to climatological factors, such as temperature, than previously recognised. Conditions in much of sub-Saharan Africa are particularly propitious for Shigella transmission, although hotspots also occur in South America and Central America, the Ganges-Brahmaputra Delta, and the island of New Guinea. These findings can inform prioritisation of populations for future vaccine trials and campaigns.

FUNDING

NASA, National Institutes of Health-The National Institute of Allergy and Infectious Diseases, and Bill & Melinda Gates Foundation.

背景

腹泻病是全球导致儿童发病和死亡的主要原因，志贺菌是一个主要的病因，针对它的疫苗可能很快就会问世。本研究的主要目的是对儿童志贺菌感染的时空变化进行建模，并绘制其在低收入和中等收入国家（LMICs）的预测流行率。

方法

从多个基于 LMIC 的研究中获取了 59 个月或以下儿童粪便样本中志贺菌阳性的个体参与者数据。协变量包括家庭层面和参与者层面的因素，由研究调查人员确定，以及从地理参考儿童位置的各种数据产品中提取的环境和水文气象变量。拟合多变量模型，并按综合征和年龄层获得流行率预测。

结果

来自 23 个国家的 20 项研究（包括中美洲和南美洲、撒哈拉以南非洲以及南亚和东南亚的地点）提供了 66563 个样本结果。年龄、症状状态和研究设计对模型性能的贡献最大，其次是温度、风速、相对湿度和土壤湿度。当降水和土壤湿度均高于平均值时，志贺菌感染的可能性超过 20%，在无并发症腹泻病例中达到 33°C 时的 43%峰值，之后下降。与未改善的卫生条件相比，改善的卫生条件使志贺菌感染的几率降低了 19%（比值比[OR]=0.81[95%CI 0.76-0.86]），露天排便使感染几率降低了 18%（OR=0.82[0.76-0.88]）。