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Norovirus

About

Norovirus is a very contagious virus that causes vomiting and diarrhea. Norovirus causes what is known as the "stomach flu." People with norovirus can shed billions of norovirus particles, and it only takes a few virus particles to make others sick. This virus can spread rapidly through daycares, long term care facilities, and other congregate facilities. You can get norovirus from:

Having direct contact with an infected person
Consuming contaminated food or water
Touching contaminated surfaces and then touching your mouth with unwashed hands

There is no specific medicine to treat people with norovirus. If you have norovirus, you should drink plenty of liquids to replace fluid lost from vomiting and diarrhea.

Symptoms

The most common symptoms of norovirus are:

Diarrhea
Vomiting
Nausea
Stomach Pain

Other norovirus symptoms may include:

Fever
Body Aches

A person usually develops symptoms 12 to 48 hours after being exposed to norovirus. Most people with the virus get better within 1 to 3 days. Due to the symptoms associated with norovirus, it is very easy to become dehydrated. Symptoms of dehydration include:

Decrease in urination
Dry mouth and throat
Feeling dizzy when standing up

Transmission

Norovirus spreads through contaminated food. Norovirus can easily contaminate food because it only takes a very small amount of virus particles to make you sick. Food can get contaminated with norovirus in many ways:

An infected person touches food with their bare hands that have feces or vomit particles on them
Food is placed on a counter or surface that has feces or vomit particles on it
Tiny drops of vomit from an infected person spray through the air and land on the food
The food was grown or harvested with contaminated water

Norovirus spreads through contaminated water. Recreational or drinking water can get contaminated with norovirus and make you sick or contaminate your food. This can happen:

At the source such as when a septic tank leaks into a well
When an infected person vomits or poops in the water
When the water isn't treated properly, such as not enough chlorine

Norovirus spreads through sick people and contaminated surfaces. Surfaces can get contaminated with norovirus in many ways, including when:

An infected person touches the surface with their bare hands that have feces or vomit particles on them
An infected person vomits or has diarrhea that splatters onto surfaces
Food, water, or objects that are contaminated with norovirus are placed on surfaces

How to prevent person-to-person transmission of norovirus: