Does pin worms cause anal mucus?

I took my son to doctor today with these symptoms: anal redness and itching with a clear mucus discharge and occasional light bloody look. Diagnosis: pin worms, the itching and scratching had caused a bacterial infection as well. Treatment: antibiotics for infection and a prescription anti-parasitic medication. They say it is contagious and all family members should be treated or it will keep being passed around. Hope this helps.