冈比亚 24-59 月龄儿童中化脓性链球菌定植：减毒活流感疫苗的影响及其相关血清学反应。

Streptococcus pyogenes Colonization in Children Aged 24-59 Months in the Gambia: Impact of Live Attenuated Influenza Vaccine and Associated Serological Responses.

机构信息

Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.

Department of Infection, Immunity, and Cardiovascular Disease, Medical School, University of Sheffield, Sheffield, United Kingdom.

出版信息

J Infect Dis. 2023 Oct 3;228(7):957-965. doi: 10.1093/infdis/jiad153.

DOI:10.1093/infdis/jiad153

PMID:37246259

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10547459/

Abstract

BACKGROUND

Immunity to Streptococcus pyogenes in high burden settings is poorly understood. We explored S. pyogenes nasopharyngeal colonization after intranasal live attenuated influenza vaccine (LAIV) among Gambian children aged 24-59 months, and resulting serological response to 7 antigens.

METHODS

A post hoc analysis was performed in 320 children randomized to receive LAIV at baseline (LAIV group) or not (control). S. pyogenes colonization was determined by quantitative polymerase chain reaction (qPCR) on nasopharyngeal swabs from baseline (day 0), day 7, and day 21. Anti-streptococcal IgG was quantified, including a subset with paired serum before/after S. pyogenes acquisition.

RESULTS

The point prevalence of S. pyogenes colonization was 7%-13%. In children negative at day 0, S. pyogenes was detected at day 7 or 21 in 18% of LAIV group and 11% of control group participants (P = .12). The odds ratio (OR) for colonization over time was significantly increased in the LAIV group (day 21 vs day 0 OR, 3.18; P = .003) but not in the control group (OR, 0.86; P = .79). The highest IgG increases following asymptomatic colonization were seen for M1 and SpyCEP proteins.

CONCLUSIONS

Asymptomatic S. pyogenes colonization appears modestly increased by LAIV, and may be immunologically significant. LAIV could be used to study influenza-S. pyogenes interactions. Clinical Trials Registration. NCT02972957.

摘要

背景

在高负担环境中，对化脓性链球菌（Streptococcus pyogenes）的免疫机制了解甚少。我们探索了在冈比亚 24-59 月龄儿童中鼻内接种减毒活流感疫苗（LAIV）后鼻咽部化脓性链球菌定植情况，以及由此产生的对 7 种抗原的血清学反应。

方法

对基线时接受 LAIV（LAIV 组）或不接受 LAIV（对照组）的 320 名儿童进行了一项事后分析。通过定量聚合酶链反应（qPCR）检测基线（第 0 天）、第 7 天和第 21 天鼻咽拭子中化脓性链球菌的定植情况。定量检测抗链球菌 IgG，包括一组在获得化脓性链球菌前后有配对血清的儿童。

结果

化脓性链球菌定植的时点患病率为 7%-13%。在第 0 天为阴性的儿童中，LAIV 组和对照组分别有 18%和 11%的儿童在第 7 天或第 21 天检测到化脓性链球菌（P=.12）。与第 0 天相比，LAIV 组的定植时间比对照组（第 21 天与第 0 天的比值比，3.18；P=.003）显著增加，但对照组无显著增加（比值比，0.86；P=.79）。无症状定植后 IgG 水平升高幅度最大的是 M1 和 SpyCEP 蛋白。