I'd be interested to see more concerted research into contagious/self-replicable vaccines that are self-replicating and spreadable to a wider swath of people. That seems like a step forward in public health prevention for seasonal illnesses that we have well-engineered and safe vaccines for.

I understand the bar for deployment would need to be high to ensure that side effects are even rare compared to typical voluntary vaccinations.

This sounds like a wonderfully deadly bio-weapon platform you're planning there. Maybe introduce some gene filter to target specific population groups..? The possibilities are endless!

Self-replicating vaccines? We already have those. They're called diseases.

1) There’s no way the public would buy in to this idea. 2) This seems like a serious violation of medical ethics. 3) If we already gave a well-engineered and safe vaccine, why not take that? Supply chain and immunization itself isn’t a practical choke point: it’s vaccine accuracy for things like flu, and vaccine misinformation for something like measles. But again, take the vaccine or don’t: for most illnesses and most scenarios, you’re only hurting yourself.