Always with the substitute teachers.

Jack Black in The School of Rock appeared not to have hepatitis A or several other diseases from hanging out in all them rock and roll clubs. But he’s a celebrity.

The Grand Rapids Press in Michigan reports that an elementary school substitute teacher at Hastings Public Schools has been diagnosed with hepatitis A, leading school officials to notify parents today because the illness can be contagious.

Especially if that person doesn’t know how to properly wash their hands.

Hastings Superintendent Richard Satterlee said the district sent a letter to parents as a precaution. So far, no students have become ill.