Wednesday, November 4, 2020

Herds and Lockdowns Not Herds OR Lockdowns

Environmental & Science Education, STEM, Health, Medicine, Society

Ed Hessler

When a post begins with a glossary the prospects of what follow don't seem promising. I have a reason though; I wanted to shorten the post to the essentials. These may help you understand the basis for points Bloomberg Columnist Faye Flam makes in an essay entitled "Lockdown or herd immunity." Flam starts with a discussion of herd immunity, the Great Barrington Declaration, which pushed a herd strategy and a rip-roaring response, exactly the opposite recommendation, known as the John Snow Memorandum. Both are recommendations made by two groups of epidemiologists. So here we go.

Herd immunity: Herd immunity occurs when a large portion of a community (the herd) becomes immune to a disease, making the spread of disease from person to person unlikely. As a result, the whole community becomes protected — not just those who are immune.

Great Barrington Declaration. As infectious disease epidemiologists and public health scientists we have grave concerns about the  Great Barrington Declaration. damaging physical and mental health impacts of the prevailing COVID-19 policies, and recommend an approach we call Focused Protection.  ...The most compassionate approach that balances the risks and benefits of reaching herd immunity, is to allow those who are at minimal risk of death to live their lives normally to build up immunity to the virus through natural infection, while better protecting those who are at highest risk. We call this Focused Protection. 

John Snow Memorandum. Any pandemic management strategy relying upon immunity from natural infections for COVID-19 is flawed. Uncontrolled transmission in younger people risks significant morbidity(3) and mortality across the whole population. In addition to the human cost, this would impact the workforce as a whole and overwhelm the ability of healthcare systems to provide acute and routine care.

Furthermore, there is no evidence for lasting protective immunity to SARS-CoV-2 following natural infection(4) and the endemic transmission that would be the consequence of waning immunity would present a risk to vulnerable populations for the indefinite future. Such a strategy would not end the COVID-19 pandemic but result in recurrent epidemics, as was the case with numerous infectious diseases before the advent of vaccination. It would also place an unacceptable burden on the economy and healthcare workers, many of whom have died from COVID-19 or experienced trauma as a result of having to practise disaster medicine.

Faye Flam, as usual, provides some needed perspective which was reprinted a few days ago in the Star Tribune, October 24. I link you to its reprinting in the Richmond Times Dispatch after not being able to find it in the Star Tribune on-line. I'm working from a real newspaper copy.

We start with the no strategy approach for the COVID-19 pandemic of the current administration and move in hyperdrive to a coherent, realistic strategy. I like this one since it is based on a single word "and" not on "yes, butism."

Three points.

--Whatever the percentage of the population infected with COVID-19, this will slow down transmission. That effect is likely to be local but it can't help but help.

--Flam writes, "Here's the thing: The more precautions we take the lower the level of natural immunity we need to slow the virus."

--Flam ends with this sensible bottom line. "[T]he U.s. needs a strategy rather rather than an ever shifting set of rules. And maybe a place to start is acknowledging that social distancing and herd immunity are complements, not opposites." 

No comments:

Post a Comment