As the COVID-19 state of emergency is set to expire at the end of the month, the amount of virus is rising around the Bay Area.
"Wastewater concentrations now are concerning that they’re starting to rise up again," Marin County Public Health Officer Dr. Matthew Willis said.
The number of reported COVID-19 cases remains low, but that data has become unreliable because most people test at home and often don't report results to the county. That means public health is looking at wastewater to find the true COVID-19 level in various places.
"It’s actually a really reliable and effective way of seeing the amount of virus that's flowing in our community across the population as a whole," Willis said.
The amount of virus in Marin County's wastewater most recently peaked around the New Year and dropped toward the end of January, but now it's spiking again. Other counties are seeing a similar trend.
"Right now, our levels are similar to where they were a year ago when we had about 400 cases per day," Willis said. "If you look at the concentration in the wastewater, it correlates to that level, which is about 20 times more cases than we’re seeing reported per day now. We’re seeing about 20 cases reported."
The other key indicator is hospitalizations. So far, those are not spiking.
"It’s not like last year, but it’s definitely not going away like people feel it is," UCSF infectious disease specialist Dr. Peter Chin-Hong said.
Chin-Hong said they're still seeing patients.
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"We’re kind of just holding out steady at around 20-something patients for the last few weeks, and people are still in the ICU," Chin-Hong said. "But there are almost 500 people still dying every day in the U.S. I think it should really give us pause."
The uptick in cases comes at a time when many places, including Santa Clara County, will be closing mass vaccination and testing sites at the end of the month. That means people will need to look to their health care provider for testing and boosters.
The doctors suggest the COVID-19 levels are high enough that people should once again consider masking up in crowded indoor places for added peace of mind and protection.