Gastro-enteritis

Gastroenteritis

Gastroenteritis, commonly referred to as the "stomach flu," is an inflammation of the gastrointestinal tract, involving both the stomach and the small intestine. It leads to a combination of symptoms including diarrhea, vomiting, and abdominal pain. Gastroenteritis is typically caused by infections with viruses, bacteria, or parasites, and less commonly by non-infectious causes such as medications or food allergies.

Causes

Viral

The most common cause of gastroenteritis is viral infection. The primary viruses responsible include:

• Norovirus: Often associated with outbreaks on cruise ships, norovirus is highly contagious and can spread rapidly in closed environments.
• Rotavirus: A leading cause of severe diarrhea among infants and young children worldwide. Vaccination has significantly reduced its prevalence.
• Adenovirus: Can cause gastroenteritis, particularly in children.
• Astrovirus: Typically affects young children and the elderly.

Bacterial

Bacterial gastroenteritis is less common than viral but can be more severe. Common bacterial pathogens include:

• Escherichia coli: Certain strains, such as E. coli O157:H7, can cause severe illness.
• Salmonella: Often linked to contaminated food, such as poultry and eggs.
• Campylobacter: Commonly found in undercooked poultry.
• Shigella: Spread through contaminated water and food.

Parasitic

Parasitic infections are less common in developed countries but can occur:

• Giardia lamblia: Causes giardiasis, often from contaminated water.
• Cryptosporidium: Can cause outbreaks linked to contaminated water supplies.

Symptoms

The symptoms of gastroenteritis can vary depending on the cause but generally include:

• Diarrhea
• Vomiting
• Abdominal cramps
• Nausea
• Fever
• Dehydration, especially in severe cases

Diagnosis

Diagnosis of gastroenteritis is primarily clinical, based on the symptoms and history of exposure. Laboratory tests may be conducted to identify the specific pathogen, especially in severe cases or outbreaks. These tests can include stool cultures, rapid antigen tests, and PCR assays.

Treatment

The mainstay of treatment for gastroenteritis is supportive care:

• Rehydration: Oral rehydration solutions (ORS) are recommended to prevent dehydration. In severe cases, intravenous fluids may be necessary.
• Diet: A bland diet may be recommended during recovery. The BRAT diet (bananas, rice, applesauce, toast) is often suggested.
• Medications: Antiemetics and antidiarrheal medications may be used in certain cases, but antibiotics are generally reserved for specific bacterial infections.

Prevention

Preventive measures include:

• Vaccination: Rotavirus vaccines are effective in preventing rotavirus gastroenteritis in children.
• Hygiene: Proper handwashing and food safety practices can reduce the risk of infection.
• Safe Water: Ensuring access to clean drinking water and proper sanitation.

Epidemiology

Gastroenteritis is a common condition worldwide, affecting millions of people each year. It is a leading cause of morbidity and mortality in children under five years of age, particularly in developing countries.

Also see

• Diarrhea
• Vomiting
• Dehydration
• Foodborne illness
• Infectious disease