Norovirus is a highly contagious infection. It's a leading cause of illness and outbreaks from contaminated food in the U.S., and is often described by those affected as a stomach flu. "When most people refer to a stomach flu, they’re not referring to influenza at all," says Dr. Pritish Tosh, an infectious diseases specialist at Mayo Clinic. "They’re usually referring to norovirus or a series of other gastrointestinal viruses that cause diarrhea and vomiting."
"Thankfully, these infections are generally self-limited, being within 24 or 48 hours, people feel better," Dr. Toah says. "But it’s an uncomfortable 24 to 48 hours. You have nausea, vomiting and diarrhea."
The best way to prevent the spread of norovirus is good hand hygiene. "Norovirus is spread fecal-oral, meaning, often by hands that have been in contact with stool. So it’s important that people who are sick with a norovirus are washing their hands and not preparing food for other people," Dr. Tosh says.
Norovirus can spread easily, especially in enclosed places, such as day care centers, nursing homes, schools and cruise ships. Noroviruses are difficult to wipe out because they can withstand hot and cold temperatures, as well as most disinfectants.
The Centers for Disease Control and Prevention (CDC) says norovirus often is associated with cruise ships, though, statistically, outbreaks onboard are infrequent. One reason for the association may be outbreaks on cruise ships are tracked and monitored more quickly than on land.
If anyone is concerned about norovirus on a cruise ship, Dr. Tosh says, "One thing somebody can do is go to the CDC website, and look at the cruise ship they’re about to be on. They have a listing about how many outbreaks that particular cruise ship has had."
Antibiotics will not treat norovirus because it is a viral — not a bacterial — infection. Most people will feel better in a few days.