What to Know About California’s Covid Surge

Given how back to normal California can feel nowadays, hearing about rising Covid cases can catch some of us off guard.Credit…Ariana Drehsler for The New York Times

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Once again, we’re in the middle of a summer Covid-19 surge.

This shouldn’t be surprising: Since 2020, there has been a swell in cases in the winter and again in the summer. But given how back to normal California can feel nowadays, hearing about rising Covid cases can catch some of us off guard.

Here’s what you need to know.

Covid never stopped circulating in our communities, and new variants continue to regularly appear on the scene. Currently, two of these variants, known as KP.3 and KP.2, are gaining traction and have been fueling a nationwide rise in cases since May.

We know that cases are rising because the Centers for Disease Control and Prevention tests sewage for the virus at more than 1,000 wastewater sites across the country, which provides a window into viral trends in a community. This data has become particularly useful as people increasingly take Covid tests at home and may not report their results. And wastewater surveillance can detect Covid in a region even when people aren’t experiencing symptoms or testing.

The wastewater data shows that as of early July, Covid levels nationwide were about as high as they were in March, at the tail end of the last winter surge. The C.D.C. considers that level of spread to be high.

In California, however, Covid levels are considered very high by the C.D.C., according to data from the state’s 43 wastewater reporting sites. There are only three states — Florida, Nevada and Oregon — where Covid is spreading at higher rates, the data shows. The last time levels were this elevated in California was in January, much closer to the peak of our winter surge.