A good reference reviewing the available evidence on the relation between smoking, vaping and COVID-
19 is the article written by Farsalinos, Barbouni and Nyaura  (see also the professional blog entry of
Farsalinos ). The authors conclude after reviewing the data from five studies on patients infected by
SARS-CoV-2 that the relation between smoking cigarettes and the severity of COVID-19 in infected
Chinese patients is uncertain and even protective (bearing in mind that 52.1% of Chinese men smoke
whereas only 2.7% of women do).