(Between 1346 and 1350 alone, 20 million out of a total of 100 million Europeans were lost in the Great Dying or Great Pestilence, as it was originally called.) Earlier, slower ocean voyages protected overseas populations by exhausting the supply of hosts: uninfected fleas, rats, and people
doi:10.18632/oncotarget.13613 [4] [5]
Smoking and Health: Summary and Report of the Royal College of Physicians of London on Smoking in relation to Cancer of the Lung and other Diseases (UK Medical Research Council, London, 1962)
Or they just made them stronger in the ol days
See a timeline of what happens to your body when you quit smoking How successful is smoking cessation
This was my lesson from that first international trip, and it took one week of chaotic blood sugars to learn it properly