How to prevent norovirus

Cases of norovirus are spiking in the U.S. along with other illnesses in what some are calling a "quad-demic" of viruses.

Often referred to as the stomach flu, noroviruses aren't actually part of the same class of viruses as influenza. Causing one to three days of symptoms, including nausea, vomiting, diarrhea and stomach pains, norovirus can easily spread and is difficult to prevent.

While norovirus may only cause symptoms for a few days, people can still spread the virus up to two weeks after they start feeling better.

Norovirus is primarily spread through contact with contaminated surfaces or direct contact with someone who has the virus. It can also be spread through food, particularly raw or undercooked shellfish. The virus also mutates rapidly, so even if you've had it before, you're not immune from getting it again.

The best way to prevent catching the illness is to thoroughly wash your hands using soap and hot water for 20 seconds before eating or preparing food and after interacting with someone who may be sick.

One thing that won't kill norovirus is alcohol-based hand sanitizers. While hand sanitizer is effective against many viruses, norovirus has a protein shell called a capsid that can't easily be wiped away by alcohol-based disinfecting products.

Another challenge with norovirus is that it can stay on contaminated surfaces for weeks or months. Surfaces that have been in contact with vomit or diarrhea from a sick person should be cleaned with bleach using gloves and disposable paper towels instead of rags. The bleach should be allowed to sit on the surface for at least five minutes before being wiped away.

Clothing or bedding used by someone who is sick should be washed with detergent and the hottest water possible on the longest possible wash cycle.

There is also a chance norovirus can spread through the air from vomit, so those who are in close proximity to someone with norovirus, like health care workers or parents caring for a sick child, should consider wearing a mask to prevent infection.