Also, our evolved environment had more random pathogens floating around in it than the modern world does. It looks like many auto-immune diseases are caused by

Also, our evolved environment had more random pathogens floating around in it than the modern world does. It looks like many auto-immune diseases are caused by the immune system getting restless with lack of exercise. Throwing more vaccinations at the immune system looks like it should do at least a little bit to reduce the problem.