I agree - my woo-woo alarm started to ring… any “scientific” (term thrown in to sound convincing or scary) study that sets out 2:1 ratios with a virus/disease presentation in a mixed world population 
better be damn specific (age, location, factors—-) otherwise it’s just a stupid statement to grab attention by those who don’t bother searching for accurate information.
Fuck - it’s like that “parasite remover” (not mentioning names). Read that Africa is “successful” because of it. really 
??? Don’t account for life-expectancy (much less in general), those that do grow old live with family, about half the population is rural AND they have endured many epidemics that require isolation, so they respond quicker to quarantine…