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. 2022 Apr;84(4):579-613.
doi: 10.1016/j.jinf.2021.12.018. Epub 2021 Dec 22.

RNA viral loads of SARS-CoV-2 Alpha and Delta variants in nasopharyngeal specimens at diagnosis stratified by age, clinical presentation and vaccination status

Rosa Costa  1 , Beatriz Olea  1 , María Alma Bracho  2 , Eliseo Albert  1 , Paula de Michelena  1 , Cecilia Martínez-Costa  3 , Fernando González-Candelas  2 , David Navarro  4
Affiliations

RNA viral loads of SARS-CoV-2 Alpha and Delta variants in nasopharyngeal specimens at diagnosis stratified by age, clinical presentation and vaccination status

Rosa Costa et al. J Infect. 2022 Apr.
No abstract available

Keywords: B.1.1.7 variant; B.617.2 variant; COVID-19; SARS-CoV-2 RNA load; Upper respiratory tract.

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Conflict of interest statement

Declaration of Competing Interest The authors declare no conflicts of interest.

Figures

Fig. 1
Fig. 1
Initial SARS-CoV-2 RNA loads in nasopharyngeal specimens from unvaccinated individuals infected by either Alpha (B.1.1.7) or Delta (B.1.617.2) variants. The Alpha lineage was confirmed by whole-genome sequencing in 108 cases, whereas in the remaining 230 it was inferred by S-gene target failure (SGTF) in the RT-PCR, as more than 95% of SGTFs detected in the Clínico-Malvarrosa Health Department belonged to that lineage within the timeframe of specimen collection (not shown). The Delta lineage was confirmed by whole-genome sequencing (n = 138) or variant-specific RT-PCR (n = 61). Whisker-plots of SARS-CoV-2 RNA loads in NP by time of sampling relative to symptoms onset are displayed separately for adults (A) and children (B). Whisker-plots of SARS-CoV-2 RNA loads in NP for asymptomatic participants are also shown separately for adults (C) and children (D). P values are shown for comparisons across groups.
Fig. 2
Fig. 2
Linear regression analysis of initial SARS-CoV-2 RNA loads from individuals infected with COVID by the Delta (A) and Alpha (B) variants according to time of sampling since symptoms onset. Regression lines best fitting SARS-CoV-2 RNA load decay are depicted.
See this image and copyright information in PMC

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