Those side effects will be listed on the vaccine manufacturers insert as well. You'd be surprised how many pharmaceuticals have "death" listed as a possible "side effect" on their inserts.

And especially with vaccines it's an important a legal thing (for the manufacturers). With the vaccine manufacturer immunity laws, the only possible way for them to be sued for an adverse reaction of any kind, is if the reaction was NOT listed on the insert as a "side effect" AND it can be proven without a shadow of doubt that the unlisted reaction was caused by the vaccine.