What to Know About the Stomach Flu

Causes, Symptoms and Treatments of Norovirus

Norovirus, often called the stomach flu or stomach bug, is highly contagious and can quickly cause your household to feel under the weather. Hand sanitizer alone is not enough to prevent the spread of this illness — making hand washing vital. Learn more about how the stomach bug spreads and how to avoid it.

How does the stomach flu spread?

Norovirus is one strain of the gastroenteritis virus, a viral infection of the stomach and intestines. The virus commonly peaks between November and April, affecting people of all ages, especially in crowded settings.

The most common way stomach flu spreads is through touch: skin-to-skin contact or touching contaminated surfaces. “It’s a highly contagious virus, and you don’t need much of the virus to be infected,” said Alan Bulbin, MD, Catholic Health Infectious Disease Specialist. “The highest risk is when you are around someone symptomatic. That’s how you can get household outbreaks.”

Is the stomach flu preventable?

Norovirus can live on surfaces for up to two weeks. Regularly practicing proper hygiene and sanitation is the best way to help prevent you and your family from getting the stomach flu. This includes:

• Washing your hands often

• Avoiding close contact with people who are sick

• Using a bleach-based cleaner to sanitize high-touch surfaces 

• Covering your mouth and nose when you cough or sneeze

What are the symptoms of the stomach flu?

For many people, stomach flu symptoms come on suddenly and quickly. Symptoms typically occur one to three days after infection and can last up to 14 days. The most common symptoms are nausea, stomach cramping, vomiting and diarrhea. Secondary side effects may also include dehydration, muscle weakness, headache and fatigue.

Additionally, a person can be contagious from a few days to two weeks after contracting the stomach virus. Most people can return to school and work 48 hours after experiencing vomiting or diarrhea, though residual symptoms such as nausea may last longer. Always consult your doctor before returning to normal activities.

How is the stomach flu treated?

The stomach flu can often be managed at home through over-the-counter medications and drinking plenty of fluids. Getting plenty of rest will also help you start to recover sooner.

Young children, older adults, and those with weakened immune systems may be at a higher risk for a severe stomach bug, which could result in hospitalization. Seek emergency medical attention if you experience the following symptoms:

• Extreme fatigue

• Bloody vomit or diarrhea

• High fever of 103 F degrees or higher

• Inability to keep liquids down

• Dehydration (excessive thirst, lightheadedness, dry mouth, dark-colored urine)

How is the stomach flu different from food poisoning?

The stomach flu and food poisoning share similar symptoms but have different causes. Food poisoning is caused by bacteria ingested when eating a contaminated food item and is not contagious. If you feel sick, visit your doctor for proper diagnosis and treatment.

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