Norovirus
Background
- Most common cause of acute gastroenteritis across all age groups
- Noroviruses cause 50-80% of all acute infectious diarrhea in the US
- More common in winter
- Fecal-oral transmission (e.g. foods touched by contaminated hands)
Clinical Features
- Onset typically 12-72h after exposure
- Symptoms last 12h-9d
- Nausea/vomiting
- Diarrhea, abdominal cramping
- +/- fever, malaise, headache
Differential Diagnosis
Diffuse Abdominal pain
- Abdominal aortic aneurysm
- Acute gastroenteritis
- Aortoenteric fisulta
- Appendicitis (early)
- Bowel obstruction
- Bowel perforation
- Gastroparesis
- Diabetic ketoacidosis
- Hernia
- Inflammatory bowel disease
- Mesenteric ischemia
- Pancreatitis
- Peritonitis
- Sickle cell crisis
- Spontaneous bacterial peritonitis
- Volvulus
Evaluation
- Clinical diagnosis
- PCR for norovirus available but rarely used
- Evaluate for other causes of symptoms
- Evaluate for hypovolemia, electrolyte abnormalities (e.g. BMP, electrolytes)
Management
- Supportive
- IVF or oral rehydration therapy
- Antiemetics, antidiarrheals
- Good hygiene super important for preventing spread!!!
- Virus shed in stool for up to 2 weeks after symptoms resolved
- Virus can be aerosolized during vomiting or flushing toilet
- Wash hands with soap and water
Disposition
- Discharge if uncomplicated and tolerating PO