Dr. Chris Belcher from Peyton Manning Children's Hospital at St. Vincent in Indianapolis, who studies pediatric infectious diseases, told TheIndyChannel.com that norovirus is one of the most infectious things on the planet and it moves through a crowd like a Ferrari.
Allison Aiello, an associate professor of epidemiology at the University of Michigan, said most people don't wash their hands properly -- it takes about 30 seconds of vigorous rubbing using hot water and soap to wash away the tiny bits of the norovirus, and that means getting under the nails, too, NBC News reported.
Aiello said people start spreading norovirus before they actually feel sick, and they could continue to spread it for as long as two weeks after they started feeling better.
"Imagine you have a food handler who uses the bathroom and they haven't washed their hands thoroughly," Aiello told NBC News in a telephone interview. "They can end up preparing a salad for the diners that evening and end up infecting a lot of people because the food isn't cooked."
A recent study by the Centers for Disease Control and Prevention in Atlanta found hand-washed dishes are especially likely to carry the virus because the water is not hot enough, Aiello said.
Some non-profit groups said about 80 percent of U.S. restaurant workers didn't get paid sick leave, so if they miss work, they don't get paid, or get fired. Food handlers, dishwashers, even staff who bus and clear tables, all could spread the germ, Aiello said.
In June, the Food Chain Workers Alliance issued a report that said only 21 percent of workers surveyed could take a paid sick day off work and more than half said they came to work sick because they could not take time off.