- It was a "worst case" scenario, as people were confined for weeks with other infected people in very close quarters. While this protected the general public from the infection, it likely maximized the spread of the virus on board the ship.
- It was a "worst case" scenario as the population on board skewed dramatically to older - and thus, more vulnerable - people.
And so to the data, which is (cautiously) reassuring:
- 83% of the passengers never caught the virus at all.
- Very elderly (80+) were infected at only a very slightly higher infection rate (75% never caught the virus)
- Almost half the passengers who did get the virus showed no symptoms at all
- The young (under 20) and old (over 50) disproportionally showed no symptoms after being infected
- Overall death rate was 1.2% (7 cases total)
Remember, this was a worst case scenario. As I said, this is (cautiously) reassuring. A detailed analysis is available here.