Lalezari's observation that we'd require doses for "10-20%" of the population is CV19 specific... for other indications (SARS1, MERS) that could be as high as 40% of the population, or for flu, 0.5-1%. Add in HIV, Cancers, potentially chronic autoimmune disorders like Crohn's, Lupus, etc... we're gonna need a bigger vat.