Norovirus Gastroenteritis - Symptoms, Causes, Diagnosis, Treatment, and Prevention

Introduction:

Gastroenteritis is a common illness seen across the world. Bacteria and parasites mainly cause it, but viruses such as norovirus, rotavirus, adenovirus, etc., are also identified to cause gastroenteritis. Gastroenteritis caused by norovirus can affect people of any age and presents symptoms such as diarrhea, vomiting, fever, abdominal pain or cramps, and dehydration. It spreads rapidly and is caused by transmission from contaminated food, water, or an infected person. In most cases, it is self-limiting, and treatment is required in severe cases of dehydration.

What Is Norovirus?

Norovirus is a single-stranded RNA (ribonucleic acid) of the calicivirus family and is the most common cause of diarrhea and gastroenteritis outbreaks. Norovirus is resistant to heating, freezing, and a few disinfectants.

Norovirus is an infectious virus called a stomach bug that causes vomiting and diarrhea. It affects people of all ages and spreads quickly due to the shedding of viruses from a person. The norovirus involved gastroenteritis commonly occurs in outbreaks within close communities such as daycare centers, cruise ships, and hospitals or nursing facilities. Norovirus presents with abdominal pain and nausea followed by diarrhea and vomiting. Norovirus has become one of the major causes of illnesses and deaths.

What Is Gastroenteritis?

Gastroenteritis is an inflammation of the gastrointestinal tract that presents with abdominal pain, vomiting, and diarrhea. Bacteria and parasites commonly cause it, and Norovirus is the first virus identified to cause gastroenteritis and is called viral gastroenteritis.

What Are The Symptoms Of Norovirus Gastroenteritis?

A person with Norovirus infection develops symptoms within 12 to 48 hours of exposure. The symptoms include

• Watery diarrhea.

• Pain or cramps in the abdomen.

• Nausea or vomiting.

• Headache.

• Body aches.

• Fever.

• Anorexia.

• Weight loss.

• Dehydration is the most common complication of viral gastroenteritis.

Dehydration Causes:

1. Extreme thirst and dry mouth.

2. Less urinating than usual.

3. Feeling tired.

4. Dark-colored urine.

5. Sunken eyes or cheeks.

6. Light-headedness or fainting.

7. Decreased skin turgor– when pinched and released, the skin does not flatten back to normal.

Dehydration in Children:

1. Thirst.

2. Lack of energy.

3. Dry mouth.

4. No tears when crying.

5. Sunken eyes or cheeks.

6. Urination less than usual or no wet diapers for 3 hours or more.

7. Dehydrated children cry with few or no tears and are unusually fussy or sleepy.

When To Seek Care?

Most viral gastroenteritis cases are not dangerous, but one should immediately see a doctor in case of dehydration. Norovirus gastroenteritis symptoms may be similar to other infections and can be determined by the following severe symptoms:

• High fever.

• Diarrhea lasting for more than two days.

• Vomiting.

• Psychological or mental changes such as lack of energy and irritability.

• Severe pain in the abdomen or rectum.

• Six or more stools in a day.

• Dehydration symptoms.

• Black or tarry stools containing blood or pus.

Infants or children, pregnant women, the elderly, and adults with a weakened immune system or any other underlying medical condition should see a doctor immediately if they have such symptoms.

What Are The Causes Of Norovirus Gastroenteritis?

The transmission of viral particles causes norovirus gastroenteritis–

• Food or drinks contaminated with norovirus.

• Touching the surface or objects contaminated with norovirus and putting fingers in the mouth.

• Direct contact with an infected person.

It can also spread when:

• A person with gastroenteritis touches food with bare hands with feces or vomit particles.

• Food is placed on a surface or counter with feces or vomit particles.

• Vomit droplets from an infected person spray through the air or food.

• Food harvested or grown with contaminated water, such as oysters, berries, or other fruits or vegetables.

• Septic tank leakage into tanks.

• An infected person poops or vomits in the water.

• Water needs to be appropriately treated.

Norovirus is the leading cause of outbreaks or illness from contaminated food in the United States. It mostly occurs in settings like restaurants, cruise ships, etc.

How To Diagnose Norovirus Gastroenteritis?

The diagnosis is based on the symptoms and, in some cases:

1. Physical examination and medical history:

• The history of symptoms and duration and severity.

• Travel history.

• Past medical history or any medications.

• Check for pulse and blood pressure for dehydration.

• Examination of fever.

• Abdominal examination for cramps or pain, or tenderness.

2. Laboratory tests involve

• Stool tests to look for signs of infection, inflammation, and digestive disorders.

• Vomitus is collected along with stool during an outbreak.

• Serum samples may be collected and tested for a greater than the four-fold rise in IgG titer to norovirus.

• Food and water samples are collected to test for norovirus in case of an outbreak caused.

What Is The Treatment For Norovirus Gastroenteritis?

In most cases, norovirus gastroenteritis gets better on its own. However, medical treatment is needed in case of dehydration by replacing fluids and electrolytes lost.

Replacing lost fluids or electrolytes can be done by drinking plenty of liquids, such as:

• Water.

• Fruit juices.

• Sports drinks.

• Broths.

• Eating saltine crackers helps replace electrolytes.

Severe dehydration requires hospitalization and treatment with fluids through IV (intravenous) fluids. Unfortunately, no specific medication is available to treat norovirus infections, and antibiotics will not treat norovirus infections. However, Probiotics are used in a few cases.

How To Prevent Norovirus Gastroenteritis?

Preventive measures include

• After using bathrooms or toilets and changing diapers, one must wash hands with soap and water before and after handling, preparing, or eating food.

• Clean the surface that has come in contact with infected stool or vomit.

• Wear masks and gloves while cleaning toilets, vomit, or stool.

• Use of disinfectants or alcohol hand rub.

• Self-isolation and avoiding handling and preparing food when infected and after symptoms stop for a few days.

• Wash clothes or linens thoroughly that are contaminated with vomit or feces.

Conclusion:

Norovirus gastroenteritis causes an acute infectious disease in people and is common worldwide. It is generally self-limiting, and hospitalization may be required in case of severe dehydration or immunocompromised conditions. Norovirus is highly contagious with a short incubation period and can survive outside the body for several days. Proper preventive measures can help prevent infection. Viral gastroenteritis occurs in close communities, hospitals, and cruise ships. Contaminated food and water are the common cause of infection.