Norovirus Infection

Norovirus Infection: Symptoms, Causes, Diagnosis, Treatment

Although Salmonella is perhaps the leading cause of food poisoning, Norovirus is increasingly becoming a plague causing more than 20 million cases of stomach flu and approximately 800 deaths each year in the United States.

Norovirus is highly contagious and one of the most common causes of food poisoning or gastroenteritis in the US.

Norovirus, also known as “stomach bug “or “winter vomiting bug,” can cause an abrupt onset of unpleasant digestive symptoms such as diarrhea, vomiting, and fever. In extreme circumstances, it can lead to dehydration.

While there are no available vaccines to prevent the onset of Norovirus infection, recovery from an active infection can occur without specific treatment. Norovirus is not a lethal infection; however, it can lead to complications in high-risk groups such as aged adults and young children.

What Causes Norovirus Infection?

It’s easy for people to misdiagnose a Norovirus infection as the stomach flu; however, these conditions are very different. Norovirus infection occurs when you ingest foods such as fresh fruits, meats, or seafood contaminated with fecal material.

You can also be infected with Norovirus if you ingest food substances handled by an infected person. Food can also be contaminated if left on a buffet for hours.

What are the Symptoms of Norovirus Infection?

Although Norovirus infection causes no serious health complications, you may experience exhausting symptoms such as:

  • Stomach cramping
  • Nausea
  • Vomiting
  • Watery diarrhea
  • Low-grade fever
  • Head or muscle aches

Norovirus may have severe consequences such as dehydration and hospitalization in older people. Symptoms usually get better in two or three days.

How is Norovirus Transmitted?

Norovirus Infection occurs after ingestion of contaminated food materials. An affected person may spread the virus through droplets in vomit. Other modes of transmission include:

  • Direct contact with an infected person.
  • Noroviruses spread when infected people vomit or have diarrhea, contaminating the environment.
  • Sharing household utensils
  • Eating contaminated food
  • Water that is contaminated with sewage
  • Putting your hands in your mouth without washing after caring for an infected person

Risk Factors for Norovirus Infection

Norovirus can affect people of all age groups; however, specific high-risk individuals are more susceptible to contracting this infection than others. Risk factors for Norovirus include:

  • Pregnancy
  • Adult above 75 years old
  • Young children below four years old
  • People with a weak immune system
  • People with other chronic diseases
  • Attending a crowded community, e.g., school, cruise ships, or resorts

It would help to handle all consumables with excellent hygiene and safety measures.

How to Prevent the Spread of Norovirus?

The most appropriate method to prevent Norovirus spread is regular handwashing with soap and water before preparing a meal. Other preventive measures include:

  • People who have a norovirus infection should not do cooking
  • Thoroughly cook seafood and avoid foods cooked without proper hygiene.
  • You should avoid working in a daycare center or healthcare facility while you’re ill.
  • Properly dispose of infected materials and clean contaminated surfaces
  • Avoid handshaking as much as possible
  • Avoid going to crowded places or traveling till symptoms are gone
  • Properly wash food and fruits before eating

How to Diagnose Norovirus?

Your doctor may use laboratory diagnostic methods like ELISA (Enzyme-Linked ImmunoSorbent Assay) and RT-PCR (reverse transcription-polymerase) to detect Norovirus.

Treatment for Norovirus Infection

Since Norovirus is a viral disease, antibiotics are ineffective in treating this infection. Besides resting and drinking enough water to avoid dehydration, your doctor can only suggest you avoid caffeine and alcohol.

Your doctor may also suggest you take juice for easy absorption. Moreover, juice replenishes your system with lost nutrients compared to plain water. Avoid taking milk during this period, as milk may trigger gastrointestinal conditions like diarrhea or stomach cramps.

You can also purchase oral rehydration drinks at convenience stores, which your doctor may recommend.


While there may not be a foolproof way to prevent Norovirus during an outbreak, preventive measures limit its spread. Always practice proper sanitation procedures.

If you or your loved ones develop this condition, provide them with electrolyte replacement as this is the best-known treatment. Consult your doctor to determine the cause of your symptoms if they persist for a few days.