Gastroenteritis Incubation Period
The incubation period for gastroenteritis varies by viral pathogen: rotavirus typically has a 2-day incubation period, norovirus 12-48 hours (most commonly 24-48 hours), adenovirus 3-10 days, calicivirus 1-3 days, and astrovirus 24-36 hours. 1
Incubation Periods by Specific Viral Pathogen
Norovirus (Norwalk-like viruses)
- Incubation period: 12-48 hours, with most cases manifesting at 24-48 hours 1
- Illness duration: 12-60 hours (mean) 1
- Symptoms include prominent nausea, vomiting, non-bloody diarrhea, and abdominal cramps 1
- Infectivity persists up to 2 days after symptom resolution 1
Rotavirus
- Incubation period: approximately 2 days 1
- Followed by vomiting for 3 days and watery diarrhea lasting 3-8 days 1
- Fever and abdominal pain occur frequently 1
- Asymptomatic viral shedding can occur the day before symptoms start and continue for a week after symptoms end 1
Adenovirus (types 40 and 41)
- Incubation period: 3-10 days 1
- Illness duration: ≥1 week, notably longer than other enteric viral pathogens 1
- Diarrhea is more prominent than vomiting or fever 1
- Respiratory symptoms often present 1
Calicivirus
- Incubation period: 1-3 days 1
- Illness duration: average of 4 days 1
- Vomiting and diarrhea are common, with upper respiratory symptoms and fever less frequent 1
Astrovirus
- Incubation period: 24-36 hours 1
- Illness duration: 1-4 days 1
- Nonspecific gastrointestinal symptoms including vomiting, diarrhea, fever, and abdominal pain 1
Clinical Application
When to Suspect Specific Pathogens
- Short incubation (12-48 hours): Consider norovirus, especially in outbreak settings involving adults and older children 1
- Intermediate incubation (1-3 days): Consider rotavirus (2 days) or calicivirus (1-3 days) 1
- Longer incubation (3-10 days): Consider adenovirus, particularly in children <2 years with prolonged diarrhea 1
Important Caveats
- Asymptomatic viral shedding can occur before symptom onset, particularly with rotavirus, making incubation period determination challenging in outbreak investigations 1
- The infective dose varies dramatically: norovirus requires only 10-100 viral particles, while rotavirus can require as few as 10 particles in children 1
- Immunocompromised patients may experience prolonged viral shedding and atypical presentation patterns 1
Transmission Considerations
- Norovirus transmission occurs through contact with excretions, aerosols, fomites, contaminated food (especially shellfish and salads), and water 1
- Rotavirus can be transmitted person-to-person with extremely high viral loads (approximately 1 trillion infectious particles/mL of stool) 1
- Presymptomatic shedding has been suspected for norovirus on epidemiologic grounds but not proven in volunteer studies 1