What is the treatment for Norovirus infections?

Norovirus Treatment

Norovirus infection has no specific antiviral treatment and management is entirely supportive, focusing on oral or intravenous rehydration therapy to prevent dehydration-related complications. 1, 2

Supportive Care: The Cornerstone of Management

Hydration Management

• Oral rehydration therapy is the primary treatment for most patients with norovirus gastroenteritis. 3
• Escalate to intravenous fluid therapy when oral intake is inadequate or signs of severe dehydration are present. 3
• Approximately 10% of norovirus patients require medical attention, including hospitalization for dehydration management. 3

Expected Clinical Course

• Symptoms typically resolve within 1-3 days in healthy individuals, with an incubation period of 12-48 hours. 1
• The illness is characterized by acute onset of nonbloody diarrhea, vomiting, nausea, abdominal cramps, and sometimes low-grade fever. 1

Special Populations Requiring Heightened Attention

Immunocompromised Patients

• Norovirus can cause prolonged, life-threatening illness in immunocompromised individuals, lasting weeks to years rather than days. 4, 5
• These patients may develop villous atrophy leading to severe malnutrition, dehydration, electrolyte imbalance, and continuous viral shedding. 5
• Several experimental treatments have been reported in case series (nitazoxanide, ribavirin, enterally administered immunoglobulin) but lack robust evidence and are not FDA-approved for this indication. 5

Elderly and Pediatric Patients

• Young children and elderly persons are at higher risk for prolonged illness courses lasting 4-6 days. 3
• Elderly patients in long-term care facilities face increased mortality risk and should be considered for hospitalization with severe symptoms. 3, 6

Infection Control: Critical to Prevent Transmission

Hand Hygiene (Most Important Preventive Measure)

• Handwashing with soap and running water for at least 20 seconds is the single most effective method to prevent norovirus transmission. 1, 2
• Alcohol-based hand sanitizers (≥70% ethanol) can serve only as an adjunct between proper handwashings but should never substitute for soap and water. 1, 2
• The limited efficacy of alcohol-based sanitizers against norovirus is a critical pitfall to avoid. 2, 3

Isolation and Exclusion

• Isolate ill patients until 24-48 hours after symptom resolution in institutional settings (hospitals, long-term care facilities, cruise ships). 1, 2, 3
• Exclude ill food handlers, childcare workers, and healthcare workers until 48-72 hours after symptom resolution. 1, 2
• Do not require negative stool results before returning to work—this is unnecessary and impractical. 2, 3

Environmental Disinfection

• Disinfect contaminated surfaces using chlorine bleach solution at 1,000-5,000 ppm (1:50 to 1:10 dilution of household bleach) or EPA-approved disinfectants. 1, 2
• Pay particular attention to bathrooms and high-touch surfaces such as door knobs and handrails. 2
• Initial cleaning to remove soiling must precede disinfection. 1

When to Escalate Care

Hospitalization Indications

• Severe dehydration unresponsive to oral rehydration therapy. 3
• Elderly patients or those in long-term care facilities with significant symptoms. 3
• Immunocompromised patients with prolonged symptoms beyond typical 1-3 day course. 4, 5

Persistent Symptoms Beyond One Week

• Atypical presentation requiring evaluation for alternative diagnoses and assessment for complications. 3
• Consider prolonged norovirus illness in vulnerable populations (immunocompromised, elderly, young children). 3

Critical Pitfalls to Avoid

• Never rely on alcohol-based hand sanitizers as primary hand hygiene—they have minimal efficacy against norovirus. 2, 3
• Do not underestimate the severity of illness in immunocompromised patients—this population requires aggressive supportive care and monitoring. 4, 5
• Avoid bare-hand contact with ready-to-eat foods as an additional preventive measure. 1, 2
• Recognize that viral shedding can continue for an average of 4 weeks following infection, though this does not necessarily indicate ongoing contagiousness. 3

No Role for Antimicrobials or Antivirals in Routine Care

• There are no FDA-approved antiviral medications for norovirus treatment. 4
• Antibiotics have no role in management as norovirus is a viral pathogen. 7
• Experimental antivirals (favipiravir, others) remain investigational and are not available for clinical use. 5