Just a thought. Could the variation in mortality between Italy and Japan be linked to Italy’s high immigration rate?
Australia has a zero COVID-19 mortality rate so far (22 cases, 18 recovered 4 still sick/recovering?).
Overall for cases outside mainland China...there have been 2800 cases with 45 deaths (Iran has 16 {doubtful #} reported deaths w/only 95 {doubtful #} cases) for a very approx “mortality rate” of 1.6% outside of China...compared with regular flu in the U.S., averaging about 1.3%.
Flu #’s:
https://www.cdc.gov/flu/about/burden/
https://www.cdc.gov/flu/about/burden/2016-2017.html