"If you look back on it... none of the counties that had such a mask mandate showed any benefit," said Dr. Bela Matyas, the health officer for Solano County. "All of them should have seen a reduction in disease within at most two weeks, none of them did."
For months Matyas has said requiring masks for vaccinated people indoors didn't make sense, adding county data didn't support that's where transmission was occurring. However, Solano County has consistently reported the highest case rate in the Bay Area. According to ABC7's data analysis, the county currently reports 10,118 cases per every 100,000 people.
"I'd be willing to bet that the indoor mask mandate definitely had an effect in the decrease in cases," Sonoma County Public Health Oficer Dr. Sundari Mase said, but added success can't be attributed to just one intervention "because there's many things going on here...vaccine verification, mandate, masking, etc."
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Sonoma County's case rate did not reach the height of Solano's during the latest surge. Yet, health officials say there have been more than 220 cases of viral spread traced to indoor events like restaurants and bars.
"I do think it's hard to know how much higher that would be if we didn't have a mask requirement," Mase said.
Solano is the only county out of the Bay Area that hasn't left the high transmission category more than once since August 1st, according to CDC data. Solano only had one day where transmission went down from high to substantial, which was on September 27. Currently, out of the eight other counties, every other one except for Napa is in the substantial transmission category.
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CDC COVID-19 Transmission Map by County
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"We still have a lot of disease," said Matyas. "We have higher rates of disease than other Bay Area counties, but it's not passing in indoor public spaces, but in social family gatherings."
Matyas added the county has yet to receive any evidence of the virus passing in any indoor environment since the onset of the pandemic. ABC7 requested the data backing up that statement and asked if it's available to the public.
"We investigate every case and we do contact tracing," said Matyas. "What we found was every case that we would interview would say, 'oh yeah I went to a party and three other people at the party were sick'... all those illnesses were occurring in these family and social gatherings."
RELATED: Solano Co. defends past decision to keep businesses open
Matyas also said that the term "better safe than sorry" is a philosophy, not science.
"If this mandate made a difference, we should have seen evidence of it," he added. "We should be able to look back on the past two months and see did those counties who implemented it show a faster reduction in disease than counties who didn't? The answer is no."
UCSF's Dr. George Rutherford disagrees and said we don't have enough data to make that determination yet, but added there is strong observational studies proving the importance of indoor masking.
"There is not the perfectly conducted randomized controlled trial that looked at this expressly for COVID-19," Rutherford said. "There are however an abundant amount of observational studies -- including one last week from CDC that shows masking has a huge effect on transmission, especially among people those who are unvaccinated."
Most Bay Area health officials share that sentiment and believe preventing as much disease as possible means making public health decisions on less-than-perfect data.
Dr. Matyas also added if he were to implement an indoor mask mandate it may be counterproductive, resulting in more individual reluctance to both vaccination and adherence to the rules. According to ABC7's vaccine tracker, around 56 percent of Solano County's population is fully vaccinated -- the lowest rate in the Bay Area.
VACCINE TRACKER: How California is doing, when you can get a coronavirus vaccine
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