Lower nasopharyngeal viral loads in pediatric population. The missing piece to understand SARS-CoV-2 infection in children?

Abstract

SARS-CoV-2 virus infects children but, contrary to other respiratory viruses, children tend to be asymptomatic or to have less symptoms than adults and are rarely the index case in household transmission chains. The aim of this study was to compare the relative viral loads in nasopharyngeal samples from children aged 0 to 17 years with those of an adult population. We selected 126 positive nasopharyngeal samples from children. Relative viral loads were measured by RT-PCR and the comparative ∆Ct method using primers and probes targeting the viral gene E and the human RNAseP. Relative viral loads were significantly lower in the children population than in the adult one.

Keywords: Children; Nasopharyngeal swabs; SARS-CoV2; Viral loads.

Fig. 1

Boxplots showing the RT-PCR Ct values of A) the viral gene E, B) the human RNAseP, and C) the normalization in logarithmic scale, log(DCt). gray boxes in the left are children data, white boxes in the right are adult data. Box center lines show the medians; box limits indicate the 25th and 75th percentiles; whiskers extend to 5th and 95th percentiles and outliers are represented by dots. The gray dashed line in panel C marks the 25th percentile of the children population. Graphics drawn with BoxPlotR (http://shiny.chemgrid.org/boxplotr/).