In fact the human vaccines to treat the most virulent viruses, the one's that don't kill quickly but rather maim, have worked well. Small pox is eradicated, and Polio has not been seen in Nigeria for a year. Some people get sick from Vaccines, but they likely would have the most susceptible and the carriers anyway.
What is being seen is that vaccines used in livestock for purposes other than immunization is having significant negative side effects.
To be fair we are seeing some drug resistant strains that making people sick, but those are most bacteria, and are due to the routine use of antibacterials, even when there is little evidence that there is a bacterial infection.