Friday, February 21, 2020

CORONA VIRUS update: Fomites, PPE, Mortality


These are inanimate objects like doorknobs, shared computer keyboards, surfaces where droplets from coughs and sneezes land, or where hands have touched, which may transmit the virus.

Questions that the authorities should be making every attempt to answer include the following.  

a)  What % of infections are transmitted via fomites?  (In other words, how careful should you be when touching things, including objects you cannot avoid touching, like subway turnstiles, where virus may be present?)  The danger is touching a contaminated surface, then touching your eye, nose or mouth (mucous membranes) with enough live virus to cause infection.  Good patient histories and testing of COVID survival under different environmental conditions should shed more light on this.

b)  How many viral particles are needed to cause infection?  (The authorities claim COVID was transmitted from animals.  If so, there should be an animal model of infection, enabling lab testing of infectious dose, modes of transmission, etc.)

c)  How long does this virus live on objects, under different conditions of temperature, humidity, and surface type?  This can be easily tested, and CDC should stop guessing..

d)  What kills this virus on surfaces?  Alcohol hand rub (~70%) works to destroy some viruses but not others.  It is unreliable for Norovirus, for example.  Is coronavirus killed when alcohol rub is used for, say, 20 seconds on hands?  Why hasn't CDC given us this information?  

How are hospital rooms being decontaminated effectively in China?  

Personal protective equipment 

The photos of Chinese doctors in full gear worry me more than anything.  They are dressed in maximal containment suits--identical to what would be used if the patients had Ebola.  While it is said that COVID is less contagious than SARS, which China had a lot of experience with, the PPE suits suggest they believe it is extremely contagious.


According to the South China Post, where the photo below also came from, the mortality rate is actually 10%.  This article explains why estimates of mortality rates for COVID-19 could be too high or too low at this point. 

Let me explain.  There are 20,833 recovered cases, and 2360 deaths.  Another 55,000 people are still being treated.  So adding the number of recovered plus number of deaths you have 23, 193 people whose illness is over.  Of this total, 90% recovered and 10% died.  I don't know if these numbers are accurate, but they are what has been reported from China.  They are not encouraging.  This looks to me like the repeat of the 1918 flu (except it is a coronavirus, not influenza virus).  Hopefully I will be proven wrong as we learn more, but the degree of rapid spread and the potential for prolonged incubation periods (suggesting quarantines are of limited value), the lack of effective drug treatment, and the mortality rate suggest otherwise.

We are unlikely to have enough masks and gear to deal with it.  Best thing to do right now is to practice not touching your face with your hands, and to become aware of what your hands touch, and how to touch things in ways that place yourself at less risk.  In other words, by a) using gloves, b) handwashing before touching your mucus membranes, c) perhaps using napkins or paper towels or other disposable items to shield your hands in public areas like buses, subways, toilets to avoid contamination.  Whether it will be possible to maintain a minimum 6 feet of distance between yourself and someone who is coughing or sneezing is another question. 

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