One in two adults with lab-confirmed Omicron infection remain completely unaware of their COVID-19 status, US findings show. 

In a cohort study of 210 people with evidence of seroconversion during an Omicron variant surge, 56% did not realise they had been infected, say researchers from Cedars-Sinai Medical Center in Los Angeles. 

“Findings of this study suggest that low rates of Omicron variant infection awareness may be a key contributor to rapid transmission of the virus within communities,” they write in JAMA Network Open.  

The authors identified their subset from some 2500 participants in a longitudinal serological study who had provided at least two plasma samples.