Wastewater data has become perhaps the best metric to track the spread of the virus in the U.S., but it’s an imperfect tool.The curves on some Covid graphs are looking quite steep, again.Reported levels of the virus in U.S. wastewater are higher than they have been since the first Omicron wave, according to data from the Centers for Disease Control and Prevention, though severe outcomes still remain rarer than in earlier pandemic winters.

Adults in their 20s, 30s and 40s are driving the trend. Researchers point to long Covid as a major cause.There are more Americans who say they have serious cognitive problems — with remembering, concentrating or making decisions — than at any time in the last 15 years, data from the Census Bureau shows.The increase started with the pandemic: The number of working-age adults reporting “serious difficulty” thinking has climbed by an estimated one million people.About as many adults ages 18 to 64 now report severe cognitive issues as report trouble walking or taking the stairs, for the first time since the bureau started asking the questions each month in the 2000s.