It’s The Traffic (stupid)

It’s been months since a leading research institute, Riken, published its hypothesis for the low casualty rate for covid-19, namely the cross reactivity/immunity of killer-T cells. It seems that many Japanese, or their white cells have a memory of a similar strain.

Assuming that Riken’s findings are fairly accurate/scientific, the next question should be, how did the Japanese get it?

Factors may be manifold, but one factor obviously stands out: traffic from mainland China in the form of tourists.

According to the stats from the World Bank and etc., Chinese outbound tourism has been a major factor almost anywhere. However, there can be and have been ebbs and tides in the destination area(s).

Since a virus mutates, the Japanese and the low casualty areas must have had a good deal of exposure/traffic in the recent enough past, and before the corona turned seriously malicious.

Meanwhile, for the other high-casualty areas, the opposite must have happened, and once they got this strain of the corona, they were caught off guards.

Is there any evidence to support this?

--Yes.

According to the above sources, Chinese outbound tourism seems to have been disrupted during 2017 and 2018, when anti-immigration demos and violence spread in Europe. Then, many Chinese tourists changed their destination to East Asia and South East Asia, which were perceived to be safer.

That may have been a crucial period.

The above, of course, is more or less anecdotal. But I believe a thorough analysis should at least partially explain the noticeable gap or disparity in the casualty rates from region to region.