Marin monitors detect increasing COVID-19 transmission

A face mask recommendation sign hangs near an entrance to the Marin County Civic Center in San Rafael, Calif., on Wednesday, March 1, 2023. (Alan Dep/Marin Independent Journal)

COVID-19 transmission has been spiking in Marin County in recent weeks, mirroring a trend elsewhere in the country.

“Our wastewater levels in the month of June were among the lowest we’ve seen in almost two years,” said Dr. Matt Willis, the county’s public health officer. “Since then we have seen a steady increase.”

The amount of virus detected in Marin’s wastewater on Monday was three times greater than the amount on June 29. Because most people now rely on at-home coronavirus tests instead of tests that must be processed at a lab, health officials have come to rely on wastewater testing to determine infection levels.

Willis said that Marin, unlike other areas, has not seen a corresponding rise in the number of people being hospitalized because of the virus.

This week, the Centers for Disease Control and Prevention reported a 14% rise in COVID-19 hospitalization rates nationally during the three weeks through July 22. The increase in California was 13%.

“I know right now three people with COVID, and there were times during the pandemic when I didn’t know anybody with COVID,” said Dr. John Swartzberg, clinical professor emeritus of infectious diseases and vaccinology at the University of California, Berkeley.

Although hospitalization rates remain low for more than 99% of the country, including all the Bay Area counties, they’re no longer falling either, said CDC spokesman Scott Pauley. He said the U.S. has seen COVID-19 infections rise during the last three summers, so it’s not surprising to see an uptick after a long period of declining rates.

The California Department of Public Health recently reported a statewide 7-day average percentage of positive tests at 7.6%, more than twice this year’s 3.4% low on May 5 and higher than July 2021. Bay Area counties have seen positivity rates double from June to July.

“We’re in a place in the pandemic where we’re mostly providing information and asking the public to make their own decisions,” said Dr. Sara Cody, the public health officer in Santa Clara County. “Unfortunately, with the narrative that the emergency is over, the public has heard that COVID is over and it’s not around anymore, and that’s not true. The truth is we know COVID is still circulating, and you can still get sick and miss a lot of work and miss a lot of school.”

Willis said he checked in with Marin’s three hospitals on Thursday, and they reported no significant changes in COVID-related admissions. Four patients were in local hospitals with COVID-19 symptoms that day.

“Which is really no different than when our wastewater levels were significantly lower in the month of June,” Willis said.

On June 6, the county had six patients in hospitals because of the virus.

Willis said the reason why Marin has fewer hospitalizations than other areas might be because it is the California county with the highest rate of people who are current with their vaccinations. About 42% of…