Anonymous wrote:
I can’t really argue with Darren from the perspective of self-protection – I don’t know really know enough. But I still think wearing a mask (if you absolutely must go outside) will help prevent the spread. We are talking about two different things. Why does a surgeon wear a mask when performing an appendix operation? It is not to protect against catching appendicitis. If he/she were dealing with something highly infectious, like ebola, a surgical mask would not be near good enough. Darren has not addressed the issue of protecting others and I look forward to his repost with respect and interest because perhaps I will learn something.
A mask protects others if you are sneezing or coughing (a really close-talker that spits on you is also a possibility). A powerful sneeze or cough that is completely unarrested, not sneezing in to your arm etc., will travel 3 feet or more. It is a complex mix of droplet sizes that fall out at different rates (larger particles faster). The evidence for coronavirus (SARS and COVID-19) is that it requires fairly large droplet sizes that fall out fairly quickly (within a meter or two and most droplets within a minute). The air from the rooms of patients that have had COVID-19 as well as SARS (both coronaviruses) have shown that the disease is not present in the air. There are viruses like measles that are smaller and more robust than coronavirus and can exist in smaller droplets (aerosols). This is part of the reason measles is far more contagious. The primary transmission for coronavirus is contaminated surfaces that the droplets have fallen onto or surfaces that have been touched with contaminated hands.
No one can give a single absolute number where you could avoid getting coronavirus from a nearby sneeze or cough, but I think a reasonable guess is that if you are 6' (2m) away you are unlikely to have a problem (this is a statistical probability, just like the chance that you will die dismembered in a horrible fiery car accident while driving to the grocery store) (except for Annie, I think she walks to get her groceries). In a crowded hospital setting with a lot of sick people the statistics change. If you are moving patients who cough involuntarily it is hard to distance yourself. If there are a lot of folks coughing in a small space there is a greater chance you will encounter enough of particles lingering and for the total exposure of a person tipping to the scales of being dangerous.
I think most (all ?) jurisdictions have asked sick people to stay home. If you are not sneezing or coughing or within inches of a persons face while talking, a mask is not going to protect other people. When was the last time you heard someone coughing or sneezing in public? I heard one sneeze near the beginning of the outbreak an everyone's head swivelled like they were on ball bearings.
I'm not trying to argue that masks have no purpose, just that right now the public wearing them generally does more harm than good. Arne may well be using his mask effectively, but wearing his mask encourages others to do the same. If they touch their faces more, re-use masks without sterilisation, don't social distance from a false sense of security, or buy masks that would be better used in hospitals, these all cause negative effects.
I had an acquaintance with racing car driving experience and watched him drive remarkably on a closed track. He might navigate many roads competently at twice the speed limit. Yet allowing everyone to drive at these speeds would be disastrous. He drives the speed limit like us because it is part of the common good. Wearing a mask does very little or nothing to improve your safety or the safety of others around you. Going out at all when you have coronavirus or are just coughing (the case where a mask would do good), is blatantly irresponsible.
There is not a surplus of masks. Watching the news tonight shows that there are places in Spain, Italy and New York that are all desperate for masks and other protective gear. There are huge numbers of masks being misused by the public. If there was a surplus of masks they could be moved around the world very quickly by air.
We are an international community, some of us are being hit very hard by coronavirus and for others the worst is yet to come. We can all help each other by making sure protective gear is available for health care workers so that they can care for any of our members should they fall ill.