Monday, February 14, 2022

Mask Mandates and Lockdowns

First, Johns Hopkins put out a meta-study of the effectiveness of lockdowns:

Abstract 

This systematic review and meta-analysis are designed to determine whether there is empirical evidence to support the belief that “lockdowns” reduce COVID-19 mortality. Lockdowns are defined as the imposition of at least one compulsory, non-pharmaceutical intervention (NPI). NPIs are any government mandate that directly restrict peoples’ possibilities, such as policies that limit internal movement, close schools and businesses, and ban international travel. This study employed a systematic search and screening procedure in which 18,590 studies are identified that could potentially address the belief posed. After three levels of screening, 34 studies ultimately qualified. Of those 34 eligible studies, 24 qualified for inclusion in the meta-analysis. They were separated into three groups: lockdown stringency index studies, shelter-in-place- order (SIPO) studies, and specific NPI studies. An analysis of each of these three groups support the conclusion that lockdowns have had little to no effect on COVID-19 mortality. More specifically, stringency index studies find that lockdowns in Europe and the United States only reduced COVID-19 mortality by 0.2% on average. SIPOs were also ineffective, only reducing COVID-19 mortality by 2.9% on average. Specific NPI studies also find no broad-based evidence of noticeable effects on COVID-19 mortality. 

While this meta-analysis concludes that lockdowns have had little to no public health effects, they have imposed enormous economic and social costs where they have been adopted. In consequence, lockdown policies are ill-founded and should be rejected as a pandemic policy instrument.

Prior to the 'rona, lockdowns were not considered useful responses to pandemics.  What changed, do you think?

Now let's move on to mask mandates:

Mask mandates are predicated on the effectiveness of “universal masking” in which everyone wears a mask to keep case numbers lower. One of the leaders in proposing universal masking, Monica Gandhi of UCSF, has unfairly been accused of being an anti-masker for talking about the limitations of her own strategy and the much greater importance of vaccination campaigns.

But there’s no avoiding it: The benefits of universal masking have been difficult to quantify. One controlled study in Bangladesh showed a small but statistically significant benefit — among people who consistently used masks, 7.6% got symptomatic infections compared to 8.6% in the control group. Other studies have been inconclusive.

It is intuitive that a barrier ought to prevent germs from being emitted into the air. But if that’s true, why isn’t there more evidence for the benefits of masking two years into the pandemic? Experts associated with The Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota have laid out a more complex analysis: Given the current understanding that the virus is transmitted in fine aerosol particles, it’s likely an infectious dose could easily get through and around loose-fitting cloth or surgical masks...

All those factors may explain why the states with mask mandates haven’t fared significantly better than the 35 states that didn’t impose them during the omicron wave. Rhode Island, where I live, has had a mask mandate since mid-December; nonetheless, we saw our January surge rise far higher than any other state. There’s little evidence that mask mandates are the primary reason the pandemic waves eventually fall — though much of the outrage over lifting mandates is based on that assumption. Many experts acknowledge that the rise and fall of waves is a bit of a mystery, as epidemiologist Sam Scarpino explained to me on my podcast.

What is clear is that states with high vaccination rates have fewer hospitalizations and deaths, and that booster shots are essential for anyone over the age of 65 or at high risk of severe disease.

So why are 'rona restrictions being eased throughout the United States and Canada?  I'm inclined to believe it's not the science that's changed, but the polling.

8 comments:

lgm said...

Vaccine availability is the change. The vaxxed are contagious for a shorter period of time. That's showing in the #s of those hospitalized for Covid, not for something else.

https://www.nationthailand.com/in-focus/40010798 R value diagram, showing R value of omicron behind measles, ahead of everything else

I'd like to say the availability of high quality masks for free as well as free testing, but neither are available outside of major cities in my state. Even if they were, large and medium sized groups wouldn't participate and will continue gathering and spreading amongst themselves, unmasked. There is this idea that if you know someone and they don't appear with visible symptoms, they must be free of virus so its okay to carpool, party etc. At this point, around me, everyone knows someone who has died of covid and a person who died with covid (ie had a hospital procedure and died unexpectedly, covid acquired in hospital) as well as someone who was hospitalized with covid and needed oxygen. And most of that is omicron, and people who are younger than 65, not living in, working in or visiting nursing home residents and not using public transportation...its all group gathering spread. People do not realize they need to monitor their oxygen saturation numbers; the hospital cannot save you if you present with too low o2 sat as your organs are shutting down.
-- yes, living near a major city with many seasonal refugees has been informative



Darren said...

When I asked "what has changed", I'm referring to why previous guidance had *always* been against suggesting lockdowns--until 2020. What changed, what caused epidemiological conventional wisdom to get thrown out?

lgm said...

The R value and the method of spread for Covid is different, especially the period of being contagious without symptoms.

https://fivethirtyeight.com/features/why-did-the-world-shut-down-for-covid-19-but-not-ebola-sars-or-swine-flu/

lgm said...

The R value is what prompted the change. Initially the Gov here tried a quarantine in a particular 'containment area', New Rochelle NY, but the superspreading plus exponential growth curve defeated the efforts. In 2019, the containment zone used for measles did work, but measles does not have as high an R value & the population involved was insular.

https://www.cidrap.umn.edu/news-perspective/2020/03/first-us-covid-19-containment-zone-ny-51-more-cases-massachusetts

Darren said...

And yet, the lockdowns didn't work.

lgm said...

the only groups actually locked down in the US seemed to be the cruise ship passengers and the military units. Your alma mater did well, as they tested before releasing cadets from quarantine and then formed pods & tested periodically.

Darren said...

So Johns Hopkins made up the lockdowns?

lgm said...

A "lockdown" has a particular definition. "Damn humans" is the reality vs the theory that a "lockdown" actually occurred. Can't speak for your area, but in mine people were openly bragging that large group gatherings were moved to private quarters. The death count for 2020 reflects that.