Category: Coronavirus

the staff of the Ridgewood blog

Ridgewood NJ, as the SARS-CoV-2 virus mutates over time, changes in its genetic makeup could impact the ability of certain tests to recognize and detect viral antigens. A preprint study posted to medRxiv this week raises questions about the reliability of at-home rapid antigen tests in the early days of infection with the highly mutated Omicron variant of concern (VOC). The small real-world study, which is not yet peer-reviewed, examined test results from 30 people who, because of their workplace rules, were undergoing both rapid antigen and polymerase chain reaction (PCR) tests on a daily basis. On days 0 and 1 following a positive PCR test, both of the at-home rapid antigen tests in use—Abbott BinaxNOW and Quidel QuickVue—produced false-negative results despite the presence of viral loads high enough for transmission. The researchers confirmed that 4 cases transmitted the virus between false-negative test results and noted there likely were more transmissions that were unconfirmed. On average, it took 3 days for people to test positive on a rapid antigen test after testing positive on a PCR test. The researchers shared their results with US CDC and US FDA officials and called for the real-world performance of rapid antigen tests to be reassessed for each new VOC.