Symptomatic and asymptomatic transmission of SARS-CoV-2 in K-12 schools, British Columbia, April to June 2021

We prospectively studied SARS-CoV-2 transmission at schools in an era of Variants of Concern (VoCs), offering all close contacts serial viral asymptomatic testing up to 14 days. Of 229 school close contacts, 3 tested positive (1.3%), of which 2 were detected through asymptomatic testing. Most secondary transmission (90%) occurred in households. Routine asymptomatic testing of close contacts should be examined in the context of local testing rates, preventive measures, programmatic costs, and health impacts of asymptomatic transmission.