Every treatment is risk vs benefit. In vaccine administration this has to be carefully considered, because a treatment is being given to healthy people for prevention of disease. The only acceptable risk, barring a deadly epidemic, is a very small one.
This week a 14 year old girl became sick and died within hours of getting a condyloma vaccine, Cervarix. This was tragic, and inexplicable. It didn’t sound like an allergic reaction, it was the first shot–usually an allergy shows up after exposure.
I couldn’t think of any reason a vaccine, even if it was defective, could be so lethal. And apparently it wasn’t the vaccine at all. Natalie Morton had an undiagnosed medical condition.
Correlation doesn’t prove causation.