California is doing much better in the fight against the coronavirus. The state Department of Public Health reports that test positivity rate, a key metric showing the level of infection in the state based on diagnostic testing results, has seen much improvement. Based on Sept. 11 data, it indicates that the seven-day positivity rate was 3.6%, i.e., less than 4% of all Californians who were tested during the last week for COVID-19 were infected, and over 96% tested negative.
Our neighbors are doing even better. Santa Clara County reports a seven-day test positivity rate of 3% based on Sept. 12 data. San Francisco County reports a seven-day average test positivity rate of 2.03% based on data through Sept. 10.
San Mateo County’s COVID-19 Lab Testing Data dashboard shows a 5.7% test positivity rate based on Sept. 11 data. Unlike the aforementioned dashboards, it doesn’t provide a seven- or 14-day rolling average.
Why is this important?
The Johns Hopkins University Coronavirus Resource Center testing tracker states: On May 12, 2020, the World Health Organization (WHO) advised governments that before reopening, rates of positivity in testing (ie, out of all tests conducted, how many came back positive for COVID-19) of [sic] should remain at 5% or lower for at least 14 days.
San Mateo County would appear to have a serious COVID problem. Based on testing results, the level of infection is not only higher than our neighbors, but also higher than the state as a whole.