For random testing to find anything, you would need a large portion of the given population to be infected. By that point, you would already have detected the o

For random testing to find anything, you would need a large portion of the given population to be infected. By that point, you would already have detected the outbreak by targeted testing at hospitals (or even without any direct testing, based on the surge of patients with COVID-19 symptoms). Once the dust settles, random testing for anti-bodies will probably be useful to work out exactly what happened to better inform planning on future epidemics.