It’s a war children - seven times as many Americans have died from Covid-19 as in the Vietnam War. Like the US Marines who are taught to “Adapt or die” in dangerous combat missions. Like them we need some basic practical information on how far the minimum infectious dose can travel in airborne droplets and how long this dose remains infectious on clothing, wood and metal surfaces in order to adapt to our new environment. Lockdowns and isolation have always been temporary measures in order to give the scientists and politicians time to find a way to adapt. It is outrageous that after 10 months of on and off lockdowns, vague strategies and confusing restarts; our political and scientific leaders have not been able to give us the simple basic scientific information we need to adapt to living and working safely in the new Covid-19 era.
As a non-medical observer I find it stunning that the most practical information on how Covid-19 is spread was produced 7 months ago by a non-medical person - Jonathan Kay, and published in the non-scientific online blog Quillette last April (1). Instead of waiting for perfection like Health Canada, Kay spent weeks building a simple database and analyzing 58 known super-spreader events that had publicly available data on how the virus was passed from person to person. Kay discovered the original research of Carl Fiugge in 1899 that proved “..microbes can be transmitted ballistically through large droplets that emit at high velocity through the mouth and nose. His students continued the work and published a 1964 report in the Proceedings of the Royal Society of Medicine that “Very few, if any…droplets are produced during quiet breathing, but (instead they) are expelled during such activities as talking, coughing, blowing and sneezing”. Kay also quotes recent research by Lydia Bourouiba of MIT (2) which indicates that “… the gas cloud and its payload of pathogen-bearing droplets of all sizes can travel 23 - 27 feet (7-8m)” This study information was not included in the latest recommendations on distancing (WHO recommends 1m and CDC recommends 2 m). Bourouiba echoes Kay in saying “There is a need to understand the biophysics of host-to-host and in-host physiology, pathogenesis, and epidemiological spread of disease.”
The point is we still do not seem to have the basic science we need to produce practical guidelines that help us adapt to Covid-19. For example we need to know:
1. How far can the minimum infectious dose really be projected in the air by normal conversation vs loud conversation, shouting, singing, sneezing? Kay’s research found no major outbreaks on airplanes or in movie theatres where people are sitting close together and talking quietly. Most were in loud, crowded and alcohol-fuelled environments. This is distinction is critical to adapting workplaces, offices, stores, restaurants, bars etc. and safely re-opening our economy
2. How effective are various types of masks and face shields in protecting us and others in various indoor situations - normal conversation vs loud conversations vs Shouting, singing, coughing and sneezing? We all need to know precisely when and where to wear masks, shields or both.
3. How can we make it safe to eat and drink in restaurants when masking is impossible? For example do we need a shield in the middle of a 4 foot wide table for people outside our family group?
4. How long can the minimum infectious dose remain infections on hard surfaces (plastic shields, door handles, taps etc.) vs softer surfaces (clothing, masks, skin). For example many businesses simply put cash in a plastic bag for a few days instead of sterilizing it. And (horror) some of us do not really wash our cloth masks in hot soppy water every night.
With hundreds of thousands of cases can our vast army of bureaucrats and scientists not figure some of this out? This basic information must be available somewhere. Why can’t our political leaders, who tell us this is their top propriety, push their beaurocracies out of professional perfectionism and into emergency mode to giving us their “best guess” on the information we need to survive? Many of us will not live until the perfect rapid testing machines and perfect contact tracing app is developed. The need is now - not next month.
2. JAMA Insights, March 26, 2020:
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