ASM got everyone sick

About a week ago, one of the ASMs called off sick, so we only had two people closing on a Sunday. But because we are so short-staffed, they were back that Monday. Now, whatever they had has spread, and most of us are sick, but we all feel too guilty to call off because we don't have enough employees to cover, so we go to work sick, potentially putting other people’s health at risk. I wish the company would do the right thing and hire more people, but instead, they expect a skeleton crew to run the whole store, literally to our detriment. It shows how little they care about us and makes me wish we were in a union.