Offering Rapid COVID testing in SoHo, New York. Antigen testing detects proteins that live on the surface of the virus. We are utilizing the Sofia SARS Antigen Fluorescent Immunoassay by Quidel and the BD Veritor System for our rapid COVID testing in NYC. The Sofia test uses lateral flow immunoassay technology to detect COVID-19 while the BD test uses Chromatographic immunoassay technology. In a head to head study conducted in October 2020 by the Journal of Clinical Microbiology, it was found that the BD Veritor and Sofia were highly agreeable to a degree of 98.1%.