Boil it or bleach it

The reliable way to disinfect a lunch box after a stomach bug is heat or diluted bleach, because the viruses that cause these scares laugh at soap and cold water.

Norovirus is usually the culprit, and it’s annoyingly tough. A quick wipe with dish soap won’t cut it, and hand sanitizer is useless against it. So treat the box like a biohazard, not a dirty dish.

If your lunch box is dishwasher-safe, that’s the easy route. Run it through the hottest cycle with the heated-dry setting on, and use the sanitize cycle if your machine has one. Sustained heat above 140°F kills norovirus. For hand-wash-only boxes, mix about a third of a cup of regular household bleach into a gallon of water, wipe or soak every surface — including the lid seal, hinges, and corners — and let it sit wet for ten minutes. Then rinse everything thoroughly with clean water and air-dry.

Fabric lunch bags are the exception. Wash them in the machine on hot with regular detergent and dry on the highest heat. A sunny windowsill helps a little, but don’t trust it alone.

It’s an extra ten minutes of work. Your future self won’t want a rerun.