It is rude to expose others to illness.
Fran had been feeling sick and felt like she was going to throw up.
Fran needed some medicine for her stomach.
Fran asks her husband to run to the store for her to pick up her medicine.
Fran goes to the store herself to pick up the medicine that she needs.
Fran keeps her germs to herself and doesn't spread it to anyone outside of her house.
Fran spreads her germs to other people she gets in contact with at the store.