What is the common cause of acute gastroenteritis in adults?

From the Guidelines

Norovirus is the leading cause of acute gastroenteritis in adults, accounting for approximately 58% of foodborne illnesses, as reported by the Foodborne Diseases Active Surveillance Network (FoodNet) 1.

Common Causes of Acute Gastroenteritis in Adults

The etiology of acute gastroenteritis in adults can be attributed to various pathogens, including:

• Viral infections, with norovirus being the most prevalent, followed by other viruses such as rotavirus, adenovirus, and astrovirus
• Bacterial pathogens, including Salmonella enterica subspecies, Campylobacter, Shigella, and toxin-producing strains of E. coli, which are often associated with contaminated food or water
• Parasitic infections, such as Giardia and Cryptosporidium, although these are less common causes of gastroenteritis in adults

Management and Prevention

Most cases of viral gastroenteritis are self-limiting and resolve within 2-3 days with supportive care, including:

• Oral rehydration to prevent dehydration
• Rest to help the body recover
• A bland diet to reduce symptoms Antibiotics are generally not recommended for viral gastroenteritis but may be necessary for certain bacterial infections, depending on the severity and specific pathogen 1. Prevention strategies include:
• Proper hand hygiene to reduce the transmission of pathogens
• Safe food handling practices to prevent contamination
• Avoiding close contact with infected individuals to reduce the risk of transmission
• Avoiding high-risk foods, such as undercooked meat and seafood, unpasteurized milk, and soft cheese made with unpasteurized milk
• Using infection prevention and control measures in hospitals, childcare, and nursing home settings 1.

From the Research

Common Cause of Acute Gastroenteritis in Adults

• Norovirus is the leading cause of acute gastroenteritis in adults, responsible for an estimated 3.7 million illnesses, 320,000 outpatient visits, 69,000 emergency department visits, 39,000 hospitalizations, and 960 deaths annually in the United States 2.
• Norovirus is the most common cause of outbreaks of acute gastroenteritis in all age groups worldwide 3.
• The virus is highly contagious and can be spread directly from person to person or indirectly through contaminated food and water 3.
• Norovirus infection is characterized by symptoms such as diarrhea, vomiting, fever, headache, and stomach pain, and can be complicated by dehydration and electrolyte imbalance 3.
• There is no specific treatment for norovirus gastroenteritis, and prevention includes proper hand washing and cleaning or disinfection of contaminated surfaces 3.

Norovirus Infection in Adults

• Norovirus gastroenteritis can last for several years in immunocompromised patients, leading to severe malnutrition, dehydration, electrolyte imbalance, and continuous viral shedding 4.
• Several treatment strategies have been suggested for immunocompromised patients, including nitazoxanide, ribavirin, and enterally administered immunoglobulin, but further research is needed 4.
• The seroprevalence of norovirus among adults in the United States is high, with most adults having multiple norovirus infections over their lifetime 5.
• The overall population-adjusted seroprevalence to any norovirus was 90.0% (1999 to 2000) and 95.9% (2003 to 2004) in the US population aged 16 to 49 years 5.