My 5 Yr. Old Grandson Was Just Diagnosed With Walking

My 5 yr. old grandson was just diagnosed with walking pneumonia. My husband has been undergoing chemotherapy on an ambulatory basis.
My concern is that even though my grandson was given antibiotics today, he's supposed to be having a 7 day vacation period at our home with us and his father, our son (a divorced single parent); that this exposure could be deleterious to my husband's treatment , and to others in our home.
What do you recommend?