Speaking as somebody who is pro-vaccine, I habitually tense up when I am about to receive a shot. In my mind I know it's not going to be supremely painful, but the idea of being punctured like that and the memory of receiving shots when I was young are in the back of my mind.

A lot of anti-vax propaganda relies on fear instead of reason, and I think the way vaccines are delivered accentuates that fear. After all, even if you don't have a phobia of needles it is still natural to feel nervous when you're about to receive a shot. If there was a vaccine that (hypothetically) could be ingested and be as effective, how much would the tide turn against anti-vax propaganda?