This
is very good! But I don't want to be so arrogant as to say that even
as scientist I have never fallen into any of these traps ... I can only
say that I always try not to, and I welcome being called on it if I do!
Contagion is a probability "game", and, unfortunately, just as is the case for exponential growth phenomena, people have a hard time wrapping their brains around probability effects. Each type of virus has its one favorite mode of transmission. That is the mode in which you are most likely to be affected. For instance Measles can easily stay airborne and each case typically infects 12 to 18 others if unchecked. The number is about six for polio, smallpox, and rubella, and, f ortunately, only two to three for COVID-19. The 2-3 number says something about how it is likely to be transmitted. Earlier this month, CDC reported that the rate of symptomatic infection among a patient’s household members was 10.5%. The rate among other close contacts was 0.45%. This is consistent with the "droplet spread" mode of transmission rather than the airborne transmission of Measles. Which, again, doesn't mean that there might not been some virus "in the air...
In Asia and in Italy they have been using face masks. China made them compulsory. They stopped the virus - of course with much more severe measures than face masks, but they were part of the overall strategy. They are now donating millions of them to Italy to add to their supply (thank you, China!). Why are they not being recommended by the "authorities" here? Got tired of seeing the usual "cut and paste" explanations, and asked the following where I work (NASA Ames -- yes I am scientist there): 1. If they are recommended for health workers and close contacts why would they also not be good for more casual contact except possibly not to exhaust the supply for where they are needed most? (If so that should be mentioned). 2. It appears that folks can be asymptomatic for days and still spread the virus. That means that “I” (without symptoms) could be unknowingly be spreading the virus, and wearing a mask might be preventing that… My question and commen...
So far I've mostly tried to bring recognition and understanding for the severity of the problem we are facing. The reason is for us to be ready for, and accepting of, even the most drastic measures that will be taken. Today I'd like to speak to what the "light at the end of the tunnel" will look like ... assuming you'll want to think of it that way. I'm sure you have heard about the fact that the number of deaths in Italy has surpassed those of China. That's of course becaus e the number of cases continues to increase. What is less obvious, unless you look at appropriate graphs is that the daily rate of new cases (as % of the total) has been decreasing; and they are waiting (..and hoping) to start seeing the effect of the "national lockdown" enacted about a week ago. Look at the first graph. It shows the daily % of increase from the start. Note that it started around 25% and higher spikes... It is now down to around 15%. I's no...
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