Noroviruses are a group of virus strains that cause gastroenteritis, commonly known as the stomach flu or food poisoning, WebMD states. Gastroenteritis occurs when the stomach and large intestine are inflamed, causing nausea, stomach cramps, watery diarrhea and vomiting. Noroviruses are typically transmitted through food contamination, such as raw or undercooked shellfish. However, individuals may also spread the virus to their eyes, nose or mouth after contact with an infected surface.
Symptoms of noroviruses usually manifest within one to two days of exposure and last one to three days, Mayo Clinic notes. The viruses are distributed in human and animal feces, and they are resistant to many disinfectants and hot and cold temperatures, making it difficult to stop them from spreading. People with impaired immune systems have a higher risk of contracting these viruses, and infants and seniors are most susceptible to serious symptoms, such as malnutrition. However, the infection isn’t life-threatening for healthy children and adults.
Noroviruses are the most common cause of gastroenteritis and diarrhea, according to WebMD. Noroviruses spread rapidly through hand shaking or sharing eating utensils, so they are most likely to affect crowded environments, such as daycare centers, cruise ships and nursing homes. Other symptoms include mild fever, headaches, fatigue, chills and muscle aches. Infected individuals are at risk of dehydration if they don’t increase fluid intake to balance the depletion caused by vomiting and diarrhea.