Norovirus/Norwalk virus
Norovirus/Norwalk virus Updated: 01/29/2024 © Jun Wang, MD, PhD General features Most common cause of epidemic nonbacterial gastroenteritis Norovirus Single-stranded RNA and hexagonal capsid 5 genogroups, I, II and IV are human pathogens Highly contagious, Fecal-oral transmission Usually not severely ill Lasting 24-72 hours, usually self-limited Associated with shellfish, prepared foods, etc Diarrhea due to transient malabsorption of D-xylose and fat and inhibition of brush-border enzymes including alkaline phosphatase and trehalase Key clinical features Usually not severely ill Nausea, vomiting, moderate watery diarrhea (4-8 stools/day) Signs of volume depletion: tachycardia, hypotension, ONLY in severe cases Stools usually do NOT contain mucous or leukocytes Diagnosis Usually clinical diagnose Confirmation needed for immunocompromised patients with severe or persistent symptoms Multi-pathogen molecular tests to confirm Other pathogens need to be r...