Abstract:
Background: The contact tracing and isolation of contagious individuals are cornerstones in the control of the COVID-19 pandemic. Strategies to identify household contacts who should be isolated around index children that tested positive for SARS-CoV-2 remain to be clarified. We aimed to compare contact tracing strategies around an index child positive for SARS-CoV-2 using serological rapid diagnostic testing (RDT, chromatography immunoassay). Methods: We conducted a contact tracing study in households of index cases children in the Paris region, France, between May 8 and July 27, 2020. We compared two strategies, one using SARS-CoV-2 reverse transcriptase polymerase chain reaction (RT-PCR) and one combining RT-PCR and serological RDT, initiated once RDT was available. The contacts RT-PCR-/RDT+ were considered to have been previously infected and not requiring quarantine. The primary outcome was the proportion of contacts that could avoid quarantine with the two screening strategies. Results: We included 34 children as index cases. Median age was 7 years. They generated 184 contacts (111 adults, 73 children) tested by RT-PCR: 24/184 (13%) were positive. The strategy combining RDT and RT-PCR was performed in 120/184 contacts (77 adults, 43 children) of 26 index children: 16/120 (13%) were RT-PCR+ and 47/120 (39%) were RDT+. Among the 16 individuals who were RT-PCR+, 14 (87%) were also RDT+. Among the 104 individuals who were RT-PCR-, 33 were RDT+. Hence 33/120 (27%) individuals were not isolated. Conclusions: Following the diagnosis of SARS-CoV-2 infection in children, a strategy combining serological RDT and nasopharyngeal RT-PCR enabled us to identify around one fourth of contacts with past infection and avoid unnecessary quarantine of these individuals.
摘要:
背景:接触者追踪和隔离传染性个体是控制COVID-19大流行的基石。确定应与SARS-CoV-2检测呈阳性的索引儿童隔离的家庭接触者的策略仍有待澄清。我们旨在使用血清学快速诊断测试(RDT,色谱免疫测定)。方法:我们在巴黎地区的指数病例儿童家庭中进行了接触者追踪研究,法国,2020年5月8日至7月27日。我们比较了两种策略,一种使用SARS-CoV-2逆转录聚合酶链反应(RT-PCR),一种结合RT-PCR和血清学RDT,一旦RDT可用,就开始了。接触RT-PCR-/RDT+被认为先前已被感染,不需要隔离。主要结果是可以通过两种筛查策略避免隔离的接触者比例。结果:我们纳入了34例儿童作为指标病例。中位年龄为7岁。他们产生了184个联系人(111个成年人,73名儿童)通过RT-PCR检测:24/184(13%)为阳性。RDT和RT-PCR相结合的策略在120/184个接触者中进行(77个成年人,26名指数儿童中的43名儿童):16/120(13%)为RT-PCR+,47/120(39%)为RDT+。在RT-PCR+的16个人中,14(87%)也为RDT+。在RT-PCR-的104个人中,33分别为RDT+。因此,33/120(27%)的个体没有被隔离。结论:在诊断出儿童SARS-CoV-2感染后,血清学RDT和鼻咽RT-PCR相结合的策略使我们能够识别约1/4的既往感染接触者,并避免对这些个体进行不必要的隔离.