Covid-19 test samples and wastewater are helping health officials figure out how widely the Omicron variant might be spreading in the U.S. Another factor that is making cases easier to find: a glitch in a commonly used test.
Covid-19 test samples and wastewater are helping health officials figure out how widely the Omicron variant might be spreading in the U.S. Another factor that is making cases easier to find: a glitch in a commonly used test.