Several Mutations of the Coronavirus That Causes COVID-19 Detected in Oregon Wastewater
L452R was first identified in the U.S. last year. But it didn’t raise much concern until earlier this month, when researchers found that the percentage of cases associated with the variant had gone up to 25 percent, a stark increase from 3.8 percent in the proceeding three weeks. L452R is now associated with several outbreaks in California, including deadly surges in hospitals and nursing homes.