key: cord-346197-7g5d9x57 authors: Capecchi, E.; Di Pietro, G. M.; Luconi, E. title: Is nasopharyngeal swab comparable with nasopharyngeal aspirate to detect SARS-CoV-2 in children? date: 2020-07-05 journal: nan DOI: 10.1101/2020.07.02.20142521 sha: doc_id: 346197 cord_uid: 7g5d9x57 The tests currently used for the direct identification of SARS-CoV-2 include specimens taken from the upper and the lower respiratory tract. In our paediatric department all children undergo both nasopharyngeal swab and nasopharyngeal aspirate, performed from both nostrils, on admission and after 24 hours. We decided to compare these two methods of detection of SARS-CoV-2. Considering nasopharyngeal aspirate as the gold standard, we calculated sensitivities and specificities of nasopharyngeal swab. Based on our results, we suggest to prefer the collection of aspirates whenever possible. nasopharyngeal aspirate as the gold standard, we calculated sensitivities and specificities of nasopharyngeal swab. Based on our results, we suggest to prefer the collection of aspirates whenever possible. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 5, 2020. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 5, 2020. . https://doi.org/10.1101/2020.07.02.20142521 doi: medRxiv preprint Funding Source: No funding was secured for this study. Financial Disclosure: The authors have no financial relationships relevant to this article to disclose. The authors have no conflicts of interest relevant to this article to disclose. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 5, 2020. . https://doi.org/10.1101/2020.07.02.20142521 doi: medRxiv preprint In December 2019 appeared in China a novel coronavirus, designated as SARS-CoV-2, responsible for a pandemic respiratory disease, known as coronavirus Disease (COVID-19), with the Italian outbreak from February 2020. Children appear to have milder symptoms and less severe disease 1 . The tests currently used for the direct identification of SARS-CoV-2 include specimens taken from the upper and the lower respiratory tract 2,3 . Since the use of nasopharyngeal aspirate (NPA) seemed to be better than nasopharyngeal swab (NS) to identify respiratory virus in paediatrics 4,5 we decided to compare these methods in detecting SARS-CoV-2 in children. For clinical aims, we considered positive, to SARS-CoV-2 every patient whose NPA or NS or NPA/NS resulted positive or weak positive. Out of the 134 patients hospitalized, 18 children tested positive (prevalence 13.4%, 95% CI: 8.2%-20.4%); among the latter, 13 of them and 2 outpatient children were followed collecting their paired specimens until both resulted negative 24 hours apart. Of the 300 paired specimens evaluated: 276 were concordant, 24 were discordant, so the naïve concordance was 92.0% (95% CI: 88.3%-94.6%) with Cohen's kappa (K) 0.63. Among the paired specimens whose NPA resulted positive, 41.9% (95% CI: 28.2%-56.9%) had NS negative; while among the paired specimens whose NPA resulted negative, 2.3% (95% CI: 1.1%-5.1%) had NS positive. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 5, 2020. . https://doi.org/10.1101/2020.07.02.20142521 doi: medRxiv preprint Considering NPA as the gold standard for detection of SARS-CoV-2, we calculated sensitivities and specificities of NS. The overall sensitivity of NS was 58.1% (95% CI: 43.1%-71.8%) and the specificity was 97.7% (95% CI: 94.9-98.9%). Since the different practice in specimen collection, we divided our cohort according to the children's age (<6 or ≥ 6 years, Table 1 ). Among children under 6 years, the concordance was K=0.67. Regarding children of 6 years or older, the concordance was K=0.60. The NS has in any case a low sensitivity in detecting SARS-CoV-2 in children when referred to NPA. Our results, the first we know are available, suggest to prefer the collection of NPA whenever possible for the detection of SARS-CoV-2 in children. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted July 5, 2020. . https://doi.org/10.1101/2020.07.02.20142521 doi: medRxiv preprint Systematic Review of COVID-19 in Children Shows Milder Cases and a Better Prognosis Than Adults Upper Respiratory Tract Sampling in COVID Laboratory Diagnosis of Emerging Human Coronavirus Infections -The State of the Art Comparing Nose-Throat Swabs and Nasopharyngeal Aspirates Collected From Children With Symptoms for Respiratory Virus Identification Using Real-Time Polymerase Chain Reaction RSV Testing in Bronchiolitis: Which Nasal Sampling Method Is Best? All rights reserved. No reuse allowed without permission.(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint this version posted July 5, 2020. . https://doi.org/10.1101/2020.07.02.20142521 doi: medRxiv preprint