Oh dear. I can fully sympathize. When my children were young I had a major fear of V & D. As soon as one of the children started showing symptoms I would start shaking and come out in a cold sweat.
One of my children caught shigella, which is a form of dysentery and is, or was at the time, a notifiable disease. It was brought to the school by one of the dinner ladies returning from a holiday. Most of the school went down with it and a few families were hospitalized.
When my daughter got it, I completely isolated her and, as others have said, washed, washed and washed everything. Every time she went to the loo I swabbed the whole thing down. I was terrified of any of the rest of us getting it.
None of us got it, and of course she recovered.
I took lots of deep breaths and thought about what was the worse that could happen.
Vomit can be cleaned up. Bedding can be washed. And if the mattress is ruined, it can be replaced. It's not the end of the world
It's unpleasant, but you will get through it. Trust me.
As someone else said. If you get it, your OH will be well enough to cope with the children.
I had to cope with it one my own as my now exH was worse than useless and left me cope with all that sort of thing on my own.
Just take it calmly. You can cope.
Good luck. Hope you don't get it.