Utah will no longer offer residents rapid COVID-19 tests after an analysis showed one brand of nasal swabs used at state mobile clinics often yielded false negatives.

State health officials said Sunday that they had analyzed the results from 18,000 people who had received traditional PCR tests and rapid tests manufactured by GenBody. More than half the times a PCR test came back positive, the GenBody swab yielded a negative result.

“While rapid antigen tests are known to be less likely to identify a positive individual, the difference identified in this analysis was higher than expected,” the department said.

Reports of the false negatives came as the United States experiences an omicron variant-fueled surge, causing cases, hospitalizations and deaths to spike. In Utah last month, COVID-19 hospital admissions hit an all-time high of 125 on Jan. 18.

The rapid antigen tests, designed to detect the presence of viral proteins rather than the coronavirus itself, return results in minutes, unlike traditional molecular tests sent to labs, which can take days to process but are shown to be more accurate.

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