Author(s):
Borges, Vítor ; Isidro, Joana ; Macedo, Filipe ; Neves, José ; Silva, Luís ; Paiva, Mário ; Barata, José ; Catarino, Judite ; Ciobanu, Liliana ; Duarte, Sílvia ; Vieira, Luís ; Guiomar, Raquel ; Gomes, João Paulo
Date: 2021
Persistent ID: http://hdl.handle.net/10362/119317
Origin: Repositório Institucional da UNL
Subject(s): contact tracing; COVID-19; genome sequencing; healthcare institution; nosocomial outbreak; SARS-CoV-2; Infectious Diseases; Virology; SDG 3 - Good Health and Well-being
Description
Funding: This study is co-funded by Fundação para a Ciência e Tecnologia and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on behalf of the Research 4 COVID-19 call. This work is also a result of the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT). This work was also supported by Fundos FEDER through the ProgramaOperacionalFactores de Competitividade–COMPETE and by FundosNacionais through the Fundação para a Ciência e a Tecnologia within the scope of the project UID/BIM/00009/2019 (Centre for Toxicogenomics and Human Health -ToxOmics).
Dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in healthcare institutions affects both patients and health-care workers (HCW), as well as the institutional capacity to provide essential health services. Here, we investigated an outbreak of SARS-CoV-2 in a "non-COVID-19" hospital ward unveiled by massive testing, which challenged the reconstruction of transmission chains. The contacts network during the 15-day period before the screening was investigated, and positive SARS-CoV-2 RNA samples were subjected to virus genome sequencing. Of the 245 tested individuals, 48 (21 patients and 27 HCWs) tested positive for SARS-CoV-2. HCWs were mostly asymptomatic, but the mortality among patients reached 57.1% (12/21). Phylogenetic reconstruction revealed that all cases were part of the same transmission chain. By combining contact tracing and genomic data, including analysis of emerging minor variants, we unveiled a scenario of silent SARS-CoV-2 dissemination, mostly driven by the close contact within the HCWs group and between HCWs and patients. This investigation triggered enhanced prevention and control measures, leading to more timely detection and containment of novel outbreaks. This study shows the benefit of combining genomic and epidemiological data for disclosing complex nosocomial outbreaks, and provides valuable data to prevent transmission of COVID-19 in healthcare facilities.
