Which vaccines have been known to cause harmful side effects?

Yellow fever: Yellow fever vaccine has to be given in the right age group. In those very young & very old there have been serious consequences. It is a live vaccine & like other live vaccines, can cause temporary unpleasant side effects too. For those it is meant however, it is absolutely the right preventative manuver to avoid a potential killing disease. Given correctly, yellow fever vaccine is safe & is wise.