What is the treatment for norovirus?

Treatment for Norovirus Infection

The cornerstone of norovirus treatment is oral rehydration therapy, with intravenous fluids reserved for severe cases, while avoiding antibiotics and using anti-emetics only for severe vomiting. 1

Treatment Algorithm

First-Line Management: Rehydration

1. Oral Rehydration Therapy (ORT)

   • Primary treatment for most patients 1
   • Use oral rehydration solutions containing appropriate electrolytes
   • Encourage frequent small sips of fluid
   • For mild cases in adults, sports drinks diluted with water may be considered

2. Intravenous (IV) Fluid Therapy

   • Reserved for:
     • Severe dehydration
     • Inability to tolerate oral fluids
     • High-risk patients with significant fluid losses 1

Symptomatic Management

• Anti-emetics: May be considered for severe vomiting only 1
• Anti-diarrheal medications: Generally should be avoided, especially in children 1
• Electrolyte monitoring: Crucial for vulnerable populations (elderly, young children) 1

Special Populations Management

Children

• More susceptible to dehydration - require careful monitoring 1
• Weight-based fluid replacement is essential 1
• ORT is as effective as IV therapy for mild-to-moderate dehydration 2
• Judicious use of ondansetron can increase success of oral rehydration and minimize need for hospitalization 2

Elderly

• Higher risk of severe disease and mortality 1
• May require more aggressive fluid management and closer monitoring

Immunocompromised Patients

• May develop chronic diarrhea lasting weeks to years 1, 3
• Potential complications include:
  • Villous atrophy
  • Severe malnutrition
  • Continuous viral shedding 3
• Experimental treatments (limited evidence):
  • Nitazoxanide
  • Ribavirin
  • Enterally administered immunoglobulin 3

Infection Control Measures

• Hand hygiene: Soap and running water for at least 20 seconds (most effective) 1
  • Alcohol-based hand sanitizers (≥70% ethanol) are adjunctive only, not substitutes for handwashing
• Environmental cleaning:
  • Chlorine bleach solution (1,000–5,000 ppm concentration)
  • EPA-approved disinfectants with label claims against norovirus 1
• Isolation measures:
  • Exclude ill staff from food service, childcare, and healthcare settings until 48–72 hours after symptom resolution
  • Isolate ill patients until 24–48 hours after symptom resolution 1

Important Clinical Considerations

Duration of Illness

• Self-limiting in healthy individuals: 1-3 days
• Vulnerable populations: 4-6 days 1
• Immunocompromised patients: potentially weeks to years 3

Common Pitfalls to Avoid

• Premature return to work/school (should wait 48-72 hours after symptom resolution)
• Ineffective disinfection methods
• Overreliance on hand sanitizers instead of proper handwashing
• Inappropriate use of antibiotics (ineffective against viral infections) 1
• Assuming bloody stools rule out norovirus (they can occur in norovirus infection) 1

Emerging Treatments

While current management remains supportive, research is ongoing for antiviral therapies that may benefit immunocompromised patients with prolonged illness 4. Several norovirus vaccines are in clinical trials with promising results 2, which may eventually reduce the incidence of viral gastroenteritis.