Hedgehog Tick (Ixodes hexagonus) showing mouth parts , anus and spiracular plate .
These pesky blood suckers can grow to a fair size (15mm) when fully grown. They are not life threatening unless infestations occur usually around the eyes and ears especially in ill Hedgehogs. They should be removed if possible with tweezers . Twist slightly and pull as not to leave mouth parts behind which can become infected.   
Hedgehogs are NOT infested with fleas . In fact your domestic Dog or Cat usually carry more !!. 
Fleas that do occur are host specific (ie do not transfer to other Mammals) .