It depends what the "off sick" was caused by.
D&V then i wouldnt while they were being sick, but possibly might while they were in the 48hrs window (as long as they had stopped being sick, and what we needed was urgent)
earache..... my dc was off with earache, I dont drive so we walked to the gp surgery, then to the chemist and nipped to the co-op across the road to stock up so we didnt have to go out again.
My dc was also sent home because he "wouldnt stop shivering", got home and he was fine. I would have gone out to the shop if we needed to.
I know someone who's dc face planted a metal rail. Their mouth was a mess and dentist said they were to be careful, no running, eat only soft/liquid foods, so dc was kept off school for a week to prevent them from knocking it.... should he have to stay home even though he wasnt contagious.