Norovirus is best described as:

• A. A highly contagious gastrointestinal illness lasting 3 days to 2 weeks, spread via contaminated surfaces.
• B. A bacterial infection with short incubation.
• C. A non-infectious plant toxin.
• D. A chronic liver disease.

Answer: (A)

Norovirus is a highly contagious virus that causes acute gastroenteritis, meaning sudden stomach flu with vomiting and diarrhea. It spreads easily through the fecal-oral route and by touching contaminated surfaces or objects, and it can move quickly from person to person, especially in crowded or close-contact settings. The illness typically lasts a few days, and people can remain contagious after symptoms stop. The option that describes a highly contagious GI illness lasting a few days and spreading via contaminated surfaces matches this pattern. It’s not a bacterial infection, not a non-infectious plant toxin, and not a chronic liver disease, which is why the other choices don’t fit.