ArticleProceedings of the National Academy of Sciences of the United States of America2022
Measuring infectious SARS-CoV-2 in clinical samples reveals a higher viral titer:RNA ratio for Delta and Epsilon vs. Alpha variants.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 32 papers.
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Who cites it
32 citing papers in PubMed.
- The Combination of Nirmatrelvir and Ivermectin Exerts Strongly Synergistic Antiviral and Anti-Inflammatory Effects Against Murine Coronavirus Infection of Macrophages.International journal of molecular sciences · 2026Article
- Viral variant but not host factors associate with SARS-CoV-2 viral kinetics.Communications medicine · 2026Article
- Comparison of the analytical and clinical sensitivities of 34 rapid antigen tests with prevalent SARS-CoV-2 variants of concern during the COVID-19 pandemic in the UK.Microbiology spectrum · 2025Article
- Variant mutation G215C in SARS-CoV-2 nucleocapsid enhances viral infection via altered genomic encapsidation.PLoS biology · 2025Article
- Symptom propagation in respiratory pathogens of public health concern: a review of the evidence.Journal of the Royal Society, Interface · 2024Review
- Age-specific nasal epithelial responses to SARS-CoV-2 infection.Nature microbiology · 2024Article
- The airborne transmission of viruses causes tight transmission bottlenecks.Nature communications · 2024Article
- Longitudinal fecal shedding of SARS-CoV-2, pepper mild mottle virus, and human mitochondrial DNA in COVID-19 patients.Frontiers in medicine · 2024Article
- Delay-differential SEIR modeling for improved modelling of infection dynamics.Scientific reports · 2023Article
- Modeling identifies variability in SARS-CoV-2 uptake and eclipse phase by infected cells as principal drivers of extreme variability in nasal viral load in the 48 h post infection.Journal of theoretical biology · 2023Article
- SARS-CoV-2 viral load and shedding kinetics.Nature reviews. Microbiology · 2023Review
- Antibody protection from SARS-CoV-2 respiratory tract exposure and infection.Journal of theoretical biology · 2023Article
- Viral infectivity in paediatric SARS-CoV-2 clinical samples does not vary by age.Access microbiology · 2023Article
- Determining the Importance of Peroxisomal Proteins for Viral Infections in Cultured Mammalian Cells.Methods in molecular biology (Clifton, N.J.) · 2023Article
- Determining the impact of vaccination on SARS-CoV-2 RT-PCR cycle threshold values and infectious viral titres.Access microbiology · 2023Article
- Pulmonary lesions following inoculation with the SARS-CoV-2 Omicron BA.1 (B.1.1.529) variant in Syrian golden hamsters.Emerging microbes & infections · 2022Article
- Differences in SARS-CoV-2 Clinical Manifestations and Disease Severity in Children and Adolescents by Infecting Variant.Emerging infectious diseases · 2022Article
- Viral infectivity in pediatric SARS-CoV-2 clinical samples does not vary by age.medRxiv : the preprint server for health sciences · 2022Article
- Article
- Variations in Cell Surface ACE2 Levels Alter Direct Binding of SARS-CoV-2 Spike Protein and Viral Infectivity: Implications for Measuring Spike Protein Interactions with Animal ACE2 Orthologs.Journal of virology · 2022Article
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Abstract
Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants pose a challenge to controlling the COVID-19 pandemic. Previous studies indicate that clinical samples collected from individuals infected with the Delta variant may contain higher levels of RNA than previous variants, but the relationship between levels of viral RNA and infectious virus for individual variants is unknown. We measured infectious viral titer (using a microfocus-forming assay) and total and subgenomic viral RNA levels (using RT-PCR) in a set of 162 clinical samples containing SARS-CoV-2 Alpha, Delta, and Epsilon variants that were collected in identical swab kits from outpatient test sites and processed soon after collection. We observed a high degree of variation in the relationship between viral titers and RNA levels. Despite this, the overall infectivity differed among the three variants. Both Delta and Epsilon had significantly higher infectivity than Alpha, as measured by the number of infectious units per quantity of viral E gene RNA (5.9- and 3.0-fold increase;
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