Looks like all of these areas have had mandated face mask requirements in effect since April-May – with fines on businesses that do not enforce the rules – and yet they saw an explosion of cases in the summer and now again the fall – begging the question: Why are face masks not working?

With its backlog of cases, Los Angeles County reported the largest week-over-week increase. But even subtracting LA County leaves the statewide average 33% higher than it was a week ago.

In the Inland Empire, Riverside and San Bernardino counties each reported an increase in cases of 69% in the past week. In nearby Orange County, there was a 56% increase in cases from a week ago.

In the Bay Area, Alameda and Santa Clara counties each reported at least 37% more cases than last week, while the increase in Contra Costa County was about 26%. An uptick in cases in San Francisco two weeks ago appeared to slow in the past week, as the city reported a modest 4% gain over the past seven days.

Source: Coronavirus: California’s largest counties report uptick in cases

This July 2020 graphic indicates that face mask wearing compliance was high (80+%) in most populated counties. Other surveys put the figure at 90 percent. These are astoundingly high compliance figures. My state has an 84% compliance according to the state public health department.

In July, public health said they believe “wearing face coverings can substantially slow transmission of the coronavirus”. In August the CDC Director said this would all be over with in weeks if everyone wore a face mask. The UW IHME even made detailed forecasts by state of how many deaths would be prevented by wearing face masks[1].

“In one simulation, researchers predicted that 80 percent of the population wearing masks would do more to reduce COVID-19 spread than a strict lockdown”


It’s now almost November and compliance continues to be high (80 to 95%) in most populated areas.

Why are face masks not working as predicted?


Why are face masks not working?

  • Many face masks used are not using effective filtration materials.
  • Many people are not using the masks properly. Yesterday I saw a news photo of a crowd at a public event where face masks were mandatory for all adults. More than half of the adults had their noses uncovered, their mouth and nose uncovered, or the mask pull down around their necks!
  • Social distancing behavior changes when wearing a mask. We see this at many events where the six foot guidelines seem to vanish when people are wearing a face mask.
  • Finally, it may be because we are required to wear masks where they would have little impact in reducing the spread of the disease -and not required where they would have an impact. Specifically, 40% of new Covid-19 cases come from close household contacts; but no one wears a face mask in their own home. Another 20% or so come from close social contacts, often when meeting in someone’s home. Again, few wear a face mask in their own homes.
  • THIS IS PROBABLY WHY FACE MASKS ARE NOT HAVING MUCH EFFECT – WE WEAR THEM WHERE RISKĀ  IS LOW – AND DO NOT WEAR THEM WHERE RISK IS HIGH (INSIDE OUR HOMES). There is little chance I will catch Covid-19 while shopping at my local mega building supply store – everyone is spaced apart, and if not, its only for a very brief passage in an aisle. There is no extended close contact. But inside our homes? Tons of extended close contact.

The effect is that while masks work in theory, they do not do much in the real world.

[1] UW IHME projections have been off – by a huge amount – even an order of magnitude. Many scientists have said that IHME projections are unsuitable for any purpose. Yet many public health departments and politicians have taken their work seriously – which has led to policy choices that proved erroneous.

By EdwardM