Who needs a vaccine? R0 would presumably take a hammering if everyone smoked. Perhaps the big decline in smoking in recent decades is one of the reasons corona virus has been able to spread so effectively.
Smoking ‘may lower coronavirus risk’
The team at La Pitié Salpêtrière hospital in Paris found that smokers appeared to have five times less chance of being infected than non-smokers. However, tobacco users were likely to face graver consequences if they developed the disease. The government reminded the public that smoking kills 73,000 people a year in France.
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Professor Changeux, a neurobiologist, said that nicotine appeared to play a role in preventing the virus from entering the body. “The hypothesis is that by attaching itself to cell receptors used by the coronavirus, nicotine prevents the virus from establishing itself there,” he said.
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“It is without question that there is something in tobacco which protects people against the coronavirus but you should absolutely not conclude that you should smoke because there are many other toxic and dangerous components in cigarette smoke.”
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A Chinese study published last month by New England Journal of Medicine, found that smokers accounted for 12.6 per cent of a group of 1,099 Chinese people infected by coronavirus. Tobacco is smoked daily by 52 per cent of Chinese men.
https://www.thetimes.co.uk/article/smoking-may-lower-coronavirus-risk-l2l9wjxdh
Originally Posted by: Brian Gaze