Why anti rabies vaccine like rabipur have caused neurological adverse effects like(adem,gb syndrome), is it not safe to take (pcecv) vaccine rabipur?

Seems coincidental: Rabipur is a Purified Chick Embryo Cell Vaccine (PCECV), not known to CAUSE neurological side effects. A rare patient can get neurological problems after getting a vaccine... but that's coincidental unless the rate of neurological problems occurs more often in vaccine recipients than in non-recipients. For example, if a child dies in a car wreck after getting a vaccine, we don't blame the vaccine.