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The Alpha variant was not associated with excess nosocomial SARS-CoV-2 infection in a multi-centre UK hospital study.

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Boshier, Florencia AT 
Venturini, Cristina  ORCID logo
Stirrup, Oliver 
Guerra-Assunção, José Afonso 
Alcolea-Medina, Adela 


OBJECTIVES: Recently emerging SARS-CoV-2 variants have been associated with an increased rate of transmission within the community. We sought to determine whether this also resulted in increased transmission within hospitals. METHODS: We collected viral sequences and epidemiological data of patients with community and healthcare associated SARS-CoV-2 infections, sampled from 16th November 2020 to 10th January 2021, from nine hospitals participating in the COG-UK HOCI study. Outbreaks were identified using ward information, lineage and pairwise genetic differences between viral sequences. RESULTS: Mixed effects logistic regression analysis of 4184 sequences showed healthcare-acquired infections were no more likely to be identified as the Alpha variant than community acquired infections. Nosocomial outbreaks were investigated based on overlapping ward stay and SARS-CoV-2 genome sequence similarity. There was no significant difference in the number of patients involved in outbreaks caused by the Alpha variant compared to outbreaks caused by other lineages. CONCLUSIONS: We find no evidence to support it causing more nosocomial transmission than previous lineages. This suggests that the stringent infection prevention measures already in place in UK hospitals contained the spread of the Alpha variant as effectively as other less transmissible lineages, providing reassurance of their efficacy against emerging variants of concern.



Alpha variant, COVID-19, Lineage B.1.1.7, Nosocomial outbreaks, SARS-CoV-2, Transmissibility, Variants of concern, COVID-19, Cross Infection, Hospitals, Humans, SARS-CoV-2, United Kingdom

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J Infect

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Elsevier BV
MRC (MC_PC_19027)
UK Research and Innovation (MC_PC_19027)
COG-UK HOCI funded by COG-UK consortium. The COG-UK consortium is supported by funding from the Medical Research Council (MRC) part of UK Research & Innovation (UKRI), the National Institute of Health Research (NIHR) and Genome Research Limited, operating as the Wellcome Sanger Institute.