Management of Astrovirus Infections
Astrovirus gastroenteritis requires supportive care only, with oral rehydration therapy as the cornerstone of management—no antiviral or antimicrobial therapy is indicated. 1
Immediate Management Approach
Rehydration Protocol
- Administer reduced osmolarity oral rehydration solution (ORS) as first-line therapy for all patients with mild to moderate dehydration 1
- Give 100 mL/kg of ORS over 2-4 hours for moderate dehydration 1
- Replace ongoing stool losses with 10 mL/kg of ORS for each diarrheal stool 1
- Switch to intravenous isotonic fluids (lactated Ringer's or normal saline) only if severe dehydration, shock, altered mental status, or ORS failure occurs 1
Dietary Management
- Continue breastfeeding throughout the illness without interruption 1
- Resume age-appropriate usual diet immediately after rehydration is completed—do not restrict diet 1
- Early feeding improves outcomes and should not be delayed 1
Symptomatic Treatment
- Consider ondansetron if vomiting prevents adequate oral intake to improve ORS tolerance 1
- Never give antimotility agents (loperamide) to any pediatric patient—these are contraindicated in children under 18 years 1
Clinical Context and Disease Characteristics
Astrovirus causes self-limited gastroenteritis with an incubation period of 24-36 hours and illness duration of 1-4 days 2. The disease is clinically milder than rotavirus infection, with less dehydration and lower symptom severity scores 3. Common symptoms include vomiting, diarrhea, fever, and abdominal pain—notably, diarrhea is never bloody 2.
Children under 7 years are principally affected, though adults can be infected with mild disease 2. Astrovirus accounts for 3-5% of hospitalizations for diarrhea in children and is second only to rotavirus as a cause of viral gastroenteritis requiring hospitalization 2, 3.
Critical Pitfalls to Avoid
- Do not prescribe empiric antibiotics—astrovirus is viral and antibiotics promote resistance without benefit 1
- Do not delay rehydration while awaiting diagnostic test results—begin ORS immediately based on clinical presentation 1
- Do not restrict diet during or after rehydration—this worsens outcomes 1
- Do not use clindamycin or other antimicrobials, as they have no role in viral gastroenteritis 1
Outbreak Control Measures
When astrovirus is identified in institutional settings (day care centers, pediatric wards, nursing homes):
- Exclude symptomatic staff members from contact with susceptible persons for at least 2 days after symptom resolution 2
- Food handlers should not prepare food for the same 2-day period after symptoms resolve 2
- Personnel should wear disposable plastic gloves when in direct contact with ill persons 2
- Wash hands after each contact by rubbing all surfaces of lathered hands together vigorously 2
- Recognize that asymptomatic shedding occurs and can perpetuate outbreaks 2, 4
Special Populations
Immunocompromised Patients
While the evidence focuses primarily on immunocompetent children, aggressive supportive care with ORS remains the mainstay 1. No specific antiviral therapy exists for astrovirus even in immunocompromised hosts.
Elderly Patients
Outbreaks in nursing homes suggest immunity may wane with age 2. The same supportive care principles apply, though vigilance for dehydration is critical as constitutional symptoms may persist for weeks 2.
Day Care Settings
Younger children (≤12 months) are at greater risk of infection and more likely to have symptoms when infected 4. Outbreaks can last 11-44 days with prolonged viral shedding (up to 30 days), necessitating sustained infection control measures 4.
Transmission Prevention
Person-to-person transmission is the primary route, though contaminated water and shellfish have caused outbreaks 2. Attack rates in institutional outbreaks range from 50-70% 2. Viral shedding can occur 1-8 days before symptoms begin and persist 1-20 days after diarrhea ceases 4.