Here's some fun facts from the ER doctor.

Norovirus is ridiculously transmittable because it only takes 17 virus bodies to infect an adult human.

Each drop off vomit or fecal matter can contain millions of viruses. Using bleach to kill 99.9% of the viruses leave 1000s still active ones.

Unlike other viruses, norovirus is not killed with alcohol sanitizer. (You need bleach for surfaces, or soap and water for hands). He pointed to the Sani-Wipes, which "kill everything", and said they're not good for norovirus.

The virus itself is robust and can survive on surfaces for a few days (counters, toilets, etc), and in porous surfaces (clothing, bedding) for a week or so.

You develop immunity for 6 months or so, so you can be reinfected next year. It easily wipes out the emergency department every year or two.

Some people are naturally resistant to it due to some genetic markers.

Edit: added a few more facts, since this seems to be going viral. A really fun doctor!