It normally takes 24 to 72 hours for a person to experience signs and symptoms after exposure to norovirus. Even after you've recovered, you may continue to shed the virus in your stool for up to two weeks. With certain underlying health conditions, this shedding can last from weeks to months. Some people with norovirus infections do not show any symptoms. Despite this, they are still contagious and can spread the virus. The most common signs and symptoms of norovirus are Nausea Vomiting Stomach pain or cramps Watery or loose diarrhoea Feeling ill Low-grade fever Muscle pain