Chickens are vaccinated against salmonella (and a bunch of other things) when they are chicks in Europe. It means you don’t need to worry about shitting yourself to death, the chickens are slightly happier by not being sick, and your eggs stay fresher for longer.
It would probably add $0.005 per egg, so US producers will claim it’s communism if a regulation is brought in to vaccinate chicken, but it would be worth doing.