> The annihilation of the virus and the absorption of all of the wreckage is what gives humans immunity without actually becoming infected. Do you have a sourc

> The annihilation of the virus and the absorption of all of the wreckage is what gives humans immunity without actually becoming infected. Do you have a source for that claim? "Wreckage" would be sufficiently different from the live virus to not elicit an immune response. The live polio vaccine infects the person with an attenuated virus. The target of the polio virus is intestinal epithelial cells. There are hundreds of diseases that infect the lower digestive tract (both viral and bacterial) that clearly result from these infectious agents passing through the stomach unaltered. It may be true that many viruses are destroyed by stomach acid, but you only need a few unaltered viruses to make it through. Studies show that viruses bound to surfaces can survive stomach acid. Viruses can be bound to food or other particles which can protect them from stomach contents. https://www.sciencedirect.com/science/article/pii/S0195670120300918 https://www.sciencedirect.com/science/article/pii/S019567012... "FCV survived in synthetic gastric fluid at pH values as low as 2.5 and in some cases as low as 1.5 for at least 30 min when associated with certain materials."