Viral Gastroenteritis (Stomach Flu)

Viral gastroenteritis, commonly known as the stomach flu, is an infection of the stomach and intestines caused by viruses. It leads to inflammation of the gastrointestinal tract, resulting in diarrhea, vomiting, and abdominal discomfort. The condition is highly contagious and can spread through contaminated food, water, surfaces, or close contact with an infected person.

Although viral gastroenteritis can affect people of all ages, it is most common in children and older adults. The illness is usually self-limiting, lasting a few days, but can lead to dehydration if fluids are not adequately replaced.

Symptoms

Symptoms of viral gastroenteritis usually appear 1–3 days after exposure and may include:

• Diarrhea, which may be watery

• Nausea and vomiting

• Abdominal cramps or pain

• Fever and chills

• Headache

• Muscle aches

• Fatigue and weakness

• Loss of appetite

Symptoms typically resolve within a few days but can persist longer in severe cases or in vulnerable individuals.

Causes

Viral gastroenteritis is caused by infection with several types of viruses, including:

• Norovirus, a common cause of outbreaks in communities and healthcare settings

• Rotavirus, particularly in infants and young children

• Adenovirus and astrovirus, which can affect young children

• Enteric viruses transmitted via contaminated food, water, or surfaces

The viruses infect the lining of the intestines, causing inflammation and disruption of normal digestion and fluid absorption.

Risk Factors

Certain factors increase the likelihood of contracting viral gastroenteritis:

• Young age (infants and children) or older age

• Close contact with infected individuals (e.g., in schools or nursing homes)

• Poor hand hygiene or sanitation

• Travel to areas with contaminated food or water

• Weakened immune system

• Lack of rotavirus vaccination in children

Complications

Most cases of viral gastroenteritis are mild, but complications can occur, particularly in infants, older adults, or people with weakened immunity:

• Dehydration from excessive fluid loss

• Electrolyte imbalances

• Severe diarrhea leading to hospitalization

• Malnutrition in prolonged cases

• Secondary infections due to weakened immunity

Prompt recognition and management of dehydration are critical to prevent serious outcomes.

Prevention

Preventive measures for viral gastroenteritis focus on hygiene and vaccination:

• Frequent handwashing with soap and water

• Avoiding contact with infected individuals

• Proper handling and cooking of food

• Cleaning and disinfecting contaminated surfaces

• Rotavirus vaccination for infants as recommended

• Drinking safe, clean water

Supportive care, including fluid replacement and rest, is the mainstay of treatment to reduce symptoms and prevent dehydration.