"It’s kind of like a weather report and so the COVID weather – it’s pretty bad," said Dr. Sara Cody, public health officer. "Right now, the level of virus in the sewersheds is approaching or exceeding what we saw at the height of Omicron."
At the San Jose-Santa Clara Regional Wastewater Facility, the samples are taken underground from two large pipes carrying concentrated sludge and solid waste collected from nearly 75% of the city.
Every day, 200 milliliters of solid waste are transferred from a beaker into a large jug six separate times to get a representative sample.
"Every four hours, we pull a sample out of each line," wastewater Facility Operator Justin Sabla said. "All six samples get collected in here and then turn it into the lab to analyze."
Researchers at Stanford University test highly concentrated waste samples for COVID-19, something they have done since the early onset of the pandemic.
They are also now testing for RSV and influenza, all of which have seen significant increases in cases.
Cody said since people are not testing for the coronavirus as often as they once did, wastewater tests are a more accurate indicator of the virus’ spread, considering the entire population.
"It really is the source of truth as far as what level of virus is circulating out there," she said.
Cody recommends getting a COVID-19 booster, a flu shot, masking indoors and testing before gatherings, especially with the upcoming holidays.
"There’s a lot of viruses out there," she said. "That is why we recommend people mask up."