What are the treatments for norovirus?

Treatment of Norovirus Infection

There is no specific antiviral treatment for norovirus infection; management focuses primarily on supportive care with oral or intravenous rehydration therapy to prevent dehydration, which is the main cause of morbidity and mortality. 1

Supportive Care Approach

Fluid Management

• Oral rehydration therapy is the cornerstone of treatment for most patients 1

  • Use oral rehydration solutions to replace fluid and electrolyte losses
  • Encourage frequent small sips of clear fluids

• Intravenous fluid therapy may be necessary for:

  • Severe dehydration
  • Inability to tolerate oral fluids
  • Persistent vomiting
  • Electrolyte imbalances 1

Symptom Management

• Anti-emetics may be used for severe vomiting 1
• Anti-diarrheal medications should generally be avoided, especially in children 1
• Monitor electrolyte balance particularly in vulnerable populations (young children, elderly) 1

Special Population Considerations

High-Risk Groups

• Elderly patients require more aggressive fluid management due to higher susceptibility to dehydration 1
• Immunocompromised patients may develop prolonged infection lasting weeks to years, potentially leading to:
  • Villous atrophy
  • Severe malnutrition
  • Continuous viral shedding 2

Experimental Treatments for Immunocompromised Patients

For persistent norovirus in immunocompromised patients, case reports have suggested:

• Nitazoxanide
• Ribavirin
• Enterally administered immunoglobulin
• Favipiravir (not yet tested in humans) 2

Prevention and Control Measures

Hand Hygiene

• Proper handwashing with soap and running water for at least 20 seconds is the most effective prevention method 3
• Alcohol-based hand sanitizers (≥70% ethanol) can be used as an adjunct between handwashings but are not a substitute for soap and water 3

Environmental Disinfection

• After initial cleaning to remove soiling, disinfect surfaces using:
  • Chlorine bleach solution (1,000–5,000 ppm concentration, 1:50–1:10 dilution of household bleach)
  • EPA-approved disinfectants with label claims against norovirus 3

Isolation and Exclusion

• Exclude ill staff in food service, childcare, and healthcare settings until 48–72 hours after symptom resolution 3
• Isolate ill residents/patients in institutional settings until 24–48 hours after symptom resolution 3
• Avoid transferring patients to unaffected areas during outbreaks 3

Duration and Course of Illness

• In healthy individuals, symptoms typically resolve without treatment after 1–3 days
• More prolonged courses lasting 4–6 days can occur in:
  • Young children
  • Elderly persons
  • Hospitalized patients 3, 1

Important Caveats

• Norovirus is extremely contagious, with an infectious dose as low as 18 viral particles 1
• Virus can be detected in stool for an average of 4 weeks following infection 1
• No bare-hand contact with ready-to-eat foods is recommended to prevent transmission 3
• Vaccines are currently under development but not yet available 4, 5