支持布基纳法索家庭样本中存在人源携带侵袭性非伤寒沙门氏菌的证据。

Supporting evidence for a human reservoir of invasive non-Typhoidal Salmonella from household samples in Burkina Faso.

机构信息

Department of Clinical Sciences, Institute of Tropical Medicine (ITM), Antwerp, Belgium.

Nijmegen Institute of International Health, Radboud university medical centre, Nijmegen, the Netherlands.

出版信息

PLoS Negl Trop Dis. 2019 Oct 14;13(10):e0007782. doi: 10.1371/journal.pntd.0007782. eCollection 2019 Oct.

DOI:10.1371/journal.pntd.0007782

PMID:31609964

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6812844/

Abstract

BACKGROUND

Salmonella Typhimurium and Enteritidis are major causes of bloodstream infection in children in sub-Saharan Africa. This study assessed evidence for their zoonotic versus human reservoir.

METHODS

Index patients were children with blood culture confirmed Salmonella infection recruited during a microbiological surveillance study in Nanoro, rural Burkina between May 2013 and August 2014. After consent, their households were visited. Stool from household members and livestock (pooled samples per species) as well as drinking water were cultured for Salmonella. Isolates with identical serotype obtained from index patient and any household sample were defined as "paired isolates" and assessed for genetic relatedness by multilocus variable number tandem-repeat analysis (MLVA) and whole-genome sequencing (WGS).

RESULTS

Twenty-nine households were visited for 32/42 (76.2%) eligible index patients: two households comprised two index patients each, and in a third household the index patient had a recurrent infection. Among the 32 index patients, serotypes were Salmonella Typhimurium (n = 26), Salmonella Enteritidis (n = 5) and Salmonella Freetown (n = 1). All Typhimurium isolates were sequence type (ST)313. Median delay between blood culture sampling and household visits was 13 days (range 6-26). Salmonella was obtained from 16/186 (8.6%) livestock samples (13 serotypes) and 18/290 (6.2%) household members (9 serotypes). None of the water samples yielded Salmonella. Paired Salmonella Typhimurium isolates were obtained from three households representing four index patients. MLVA types were identical in two pairs and similar in the third (consisting of two index patients and one household member). WGS showed a strong genetic relatedness with 0 to 2 core genome SNPs difference between pairs on a household level. Livestock samples did not yield any Salmonella Typhimurium or Salmonella Enteritidis, and the latter was exclusively obtained from blood culture. Other serotypes shared by human and/or livestock carriers in the same household were Salmonella Derby, Drac, Tennessee and Muenster.

CONCLUSIONS/SIGNIFICANCE: The current study provides further evidence of a human reservoir for invasive non-Typhoidal Salmonella (iNTS) in sub-Saharan Africa.

摘要

背景

肠炎沙门氏菌和肠炎沙门氏菌是撒哈拉以南非洲儿童血流感染的主要原因。本研究评估了它们的人畜共患病与人类储主的证据。

方法

索引患者是在 2013 年 5 月至 2014 年 8 月期间在布基纳法索农村纳诺罗进行微生物监测研究期间通过血液培养确认感染沙门氏菌的儿童。在征得同意后，他们的家庭接受了访问。对家庭成员和牲畜的粪便（按物种混合样本）以及饮用水进行沙门氏菌培养。从索引患者和任何家庭样本中获得相同血清型的分离物被定义为“配对分离物”，并通过多位点可变数量串联重复分析（MLVA）和全基因组测序（WGS）评估遗传相关性。

结果

对 29 个家庭进行了 32/42（76.2%）符合条件的索引患者的访问：两个家庭各有两个索引患者，第三个家庭的索引患者有复发性感染。在 32 名索引患者中，血清型为肠炎沙门氏菌（n=26）、肠炎沙门氏菌（n=5）和弗里敦沙门氏菌（n=1）。所有肠炎沙门氏菌分离株均为 ST313。血液培养采样与家访之间的中位时间延迟为 13 天（范围为 6-26）。从 16/186（8.6%）家畜样本（13 种血清型）和 18/290（6.2%）家庭成员（9 种血清型）中获得了沙门氏菌。没有一个水样产生沙门氏菌。从三个家庭中获得了配对的肠炎沙门氏菌分离物，这些家庭代表了四个索引患者。在两个对中，MLVA 类型是相同的，在第三个对中是相似的（由两个索引患者和一个家庭成员组成）。WGS 显示出很强的遗传相关性，在家庭层面上，对之间的核心基因组 SNP 差异为 0 到 2。家畜样本未产生任何肠炎沙门氏菌或肠炎沙门氏菌，后者仅从血液培养中获得。在同一家庭中与人或/和家畜携带者共享的其他血清型为肠炎沙门氏菌德比、德雷克、田纳西州和明斯特。

结论/意义：本研究进一步提供了证据表明，在撒哈拉以南非洲，非伤寒性沙门氏菌（iNTS）的人类储主。