Viral kinetics of sequential SARS-CoV-2 infections

Abstract

The impact of a prior SARS-CoV-2 infection on the progression of subsequent infections has been unclear. Using a convenience sample of 94,812 longitudinal RT-qPCR measurements from anterior nares and oropharyngeal swabs, we compared the SARS-CoV-2 viral kinetics of first vs. second infections, adjusting for viral variant, vaccination status, and age. Relative to first infections, second infections usually featured a lower peak viral concentration and faster clearance time, especially in individuals who received a vaccine dose between their first and second infection. Furthermore, a person's relative (rank-order) viral clearance time, compared to others infected with the same variant, was similar across first and second infections; that is, individuals who had a relatively fast clearance time in their first infection tended to also have a relatively fast clearance time in their second infection. These findings provide evidence that, like vaccination, immunity from a prior SARS-CoV-2 infection shortens the duration of subsequent acute SARS-CoV-2 infections principally by reducing viral clearance time. Additionally, there appears to be an inherent element of the immune response, or some other host factor, that shapes a person's relative ability to clear SARS-CoV-2 infection that persists across sequential infections.

SARS-CoV-2 Transmission Risk Among National Basketball Association Players, Staff, and Vendors Exposed to Individuals With Positive Test Results After COVID-19 Recovery During the 2020 Regular and Postseason

“…Fifth, false-positive or false-negative results should be considered. Last, no individuals in the population were vaccinated, and these data reflect infections with the predominant COVID-19 strains during the study period and may not be applicable to variant strains of SARS-CoV-2 …”

Heterogeneous SARS-CoV-2 kinetics due to variable timing and intensity of immune responses

“…5c ). Using a slightly different data from the NBA cohort, Kissler et al found evidence that an individual’s relative clearance speed is roughly preserved across infections 37 , prompting us to investigate whether this relationship, or others, appear in our model fits. We tested whether relative viral peak, time to peak, infection duration, or area under the curve were conserved by looking at the pearson correlation and did not find any significant relationships (p<0.05).…”

High-resolution kinetics and cellular determinants of antibody response to SARS-CoV-2 over two years after COVID-19 vaccination

“…Breakthrough infections, most likely caused by Omicron, induced lower antibody levels to this VoC than to Wuhan. This observation might be the result of a combination of three factors: i) the lower immunogenicity of Omicron S compared to earlier variants, leading to reduced stimulation of immune responses 40 , ii) accelerated antigen clearance due to pre-existing immunity 44 , and iii) the impact of immune imprinting. This phenomenon refers to a preferential immune response to the first variant encountered (i.e., Wuhan included in the vaccines and/or Alpha and Delta VoCs) which limits new responses to new variants 42 .…”