Alameda County reimposed a mask mandate last month, alone among counties in the San Francisco Bay Area. Its COVID numbers were indistinguishable from its neighbors.

Eric Ting of SFGATE reports:

“The case rate curves for Alameda and Contra Costa counties are near-identical. Because the neighboring counties are similar in so many respects, if masking policy had an impact on pandemic outcomes, one would expect to see some sort of discrepancy in the graph.”

Also published over the weekend was a study from Fargo, North Dakota, which has two school districts, one of which was subject to a mask mandate for a large portion of last school year when the other was not.

The authors write:

“We observed no significant difference between student case rates while the districts had differing masking policies (IRR 0.99; 95% CI: 0.92 to 1.07) nor while they had the same mask policies (IRR 1.04; 95% CI: 0.92 to 1.16).”

We expect liberals to push for mask mandates again as we get into fall and winter. The evidence is increasingly clear that they don’t work.