The Centers for Disease Control and Prevention raised the benchmarks it uses to sort COVID-19 wastewater levels into categories in August, so a reading that once counted as high transmission may now appear as moderate, NBC News reported. The change affects the color-coded maps many families check before visiting older relatives or deciding whether to test.
The underlying virus levels did not change. What changed is where the CDC draws the lines between very low, low, moderate, high, and very high. The categories are labels on a relative scale, not counts of cases.
