We know the foods grown in most areas of the planet at this point and where they go. So we know what they’re eating. So we can use what foods lacking materials cause the greatest number of cases of oral polio virus.
From there we can build real or artificial stool sample ranges that cover all bases or regional bases of foods within an area and prepare proper recovery samples for after taking OPV to shorten or eradicate the contagious time between if taken concurrently with the vaccine. It may be helpful at first to synthesize the vaccine within the samples to make it absorbable by the body so that waste doesn’t come out but is instead destroyed by the gut biome.