What are the causes and symptoms of norovirus infection?

Norovirus, a highly contagious virus causing gastroenteritis, leads to vomiting, diarrhea, stomach cramps, and dehydration. It spreads via contaminated food, water, surfaces, or direct contact. Cases rise in winter, affecting all ages, especially the elderly. Prevention includes handwashing, cleaning surfaces, cooking seafood thoroughly, and avoiding contact with infected individuals for 48 hours.