Persistence of clinically-relevant levels of SARS-CoV2 envelope gene subgenomic RNAs in non-immunocompromised individuals.
Ontology highlight
ABSTRACT: Objectives
We aimed to evaluate associations between COVID19 severity and active viral load, and to characterise the dynamics of active SARS-CoV-2 clearance in a series of archival samples taken from patients in the first wave of COVID-19 infection in the South West of the UK.Methods
We measured subgenomic RNA (sgRNA) and E gene genomic sequences in a retrospective collection of 176 PCR-confirmed SARS-CoV-2 positive individuals, and related these to disease severity. We then assessed viral clearance dynamics in relation to symptom onset and last positive test.Results
Whilst E-gene sgRNAs declined before E-gene genomic sequences, some individuals retained sgRNA positivity for up to 68 days. 13% of sgRNA positive cases still exhibited clinically-relevant levels of virus after 10 days, with no clinical features previously associated with prolonged viral clearance times.Conclusions
Our results suggest that potentially active virus may sometimes persist beyond a 10 day period, and could pose a potential risk of onward transmission. Where this would pose a serious public health threat, additional mitigation strategies may be necessary to reduce the risk of secondary cases in vulnerable settings.
SUBMITTER: Davies M
PROVIDER: S-EPMC8757659 | biostudies-literature |
REPOSITORIES: biostudies-literature
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