Release of infectious virus and cytokines in nasopharyngeal swabs from individuals infected with non-alpha or alpha SARS-CoV-2 variants: an observational retrospective study

Archive ouverte

Monel, Blandine | Planas, Delphine | Grzelak, Ludivine | Smith, Nikaïa | Robillard, Nicolas | Staropoli, Isabelle | Goncalves, Pedro | Porrot, Françoise | Guivel-Benhassine, Florence | Guinet, Nathalie Demory | Rodary, Julien | Puech, Julien | Euzen, Victor | Bélec, Laurent | Orvoen, Galdric | Nunes, Léa | Moulin, Véronique | Fourgeaud, Jacques | Wack, Maxime | Imbeaud, Sandrine | Campagne, Pascal | Duffy, Darragh | Di Santo, James, P. | Bruel, Timothée | Péré, Hélène | Veyer, David | Schwartz, Olivier

Edité par CCSD ; Elsevier -

International audience. BackgroundThe dynamics of SARS-CoV-2 alpha variant shedding and immune responses at the nasal mucosa remain poorly characterised.MethodsWe measured infectious viral release, antibodies and cytokines in 426 PCR+ nasopharyngeal swabs from individuals harboring non-alpha or alpha variants.FindingsWith both lineages, viral titers were variable, ranging from 0 to >106 infectious units. Rapid antigenic diagnostic tests were positive in 94% of samples with infectious virus. 68 % of individuals carried infectious virus within two days after onset of symptoms. This proportion decreased overtime. Viable virus was detected up to 14 days. Samples containing anti-spike IgG or IgA did not generally harbor infectious virus. Ct values were slightly but not significantly lower with alpha. This variant was characterized by a fast decrease of infectivity overtime and a marked release of 13 cytokines (including IFN-b, IP-10 and IL-10).InterpretationThe alpha variant displays modified viral decay and cytokine profiles at the nasopharyngeal mucosae during symptomatic infection.

• Description
• Sujet/Public
• Outil
• Outil d'anticipation
• Mémoire et thèse
• Gestion