Symptoms usually begin 24 to 48 hours after ingestion of the virus but can appear as early as 12 hours after exposure. Symptoms usually last for one or two days. However, during that period, people can feel very ill and vomit, often violently and without warning, many times a day.

The most common symptoms of Norovirus are:

• Vomiting
• Diarrhea
• Nausea
• Stomach pain

Other symptoms may include

• Headache
• Muscle aches
• Fever/chills

Due to the frequent episodes of diarrhea and vomiting, dehydration can occur.

Diagnosis

Norovirus can be diagnosed by testing the stool of an infected person, ideally within 48 to 72 hours after symptoms start. Talk to your health care provider about testing or contact your local health department if you believe your illness is associated with an outbreak.

Treatment

There is no specific medicine to treat people with Norovirus illness. For treatment it is important to:

• Drink plenty of fluids so you don’t become dehydrated
• Wash your hands often and do not prepare foods for others
• Contact your health care provider (antibiotics do not treat viruses)

• Wash your hands with warm, soapy water for 20 seconds
  • After using the bathroom
  • After changing diapers
  • Before preparing foods
  • Before eating
• Clean and disinfect surfaces with a household bleach solution immediately after vomiting or diarrheal accidents
• Avoid preparing food for others while you have symptoms and for at least three days after you recover
• Carefully wash fruits and vegetables before preparing and eating them
• Cook oysters and shellfish thoroughly before eating them

Once you or your child start having symptoms of the illness, such as diarrhea, do not attend work (specifically for food handlers, healthcare workers, daycare workers) or attend daycare or school until a healthcare provider or someone from your local health department says you are clear to go back.

If you believe you have a Norovirus infection and have not yet been treated or spoken to a doctor, please be sure to do so. You should be evaluated by a doctor to confirm that you have Norovirus, and that you get the correct treatment. You should also respond to requests for interview by your local or state public health department. An investigation will take place for every confirmed case of Norovirus. It is important that you answer the call from your local or state health department so that other people in your home or near you are not at risk of getting Norovirus as well. An investigation may also look into your exposures to check if other people are at risk. If you suspect an outbreak, report it to your local health department and other public health authorities can begin to investigate a potential outbreak.