"The symptoms of a norovirus usually start between 24-48 hours after the initial infection, although they can start after as little as 12 hours. The first symptom is usually a sudden onset of nausea, which is followed by projectile vomiting and watery diarrhoea. Some people may also have: a mild fever, headaches, stomach cramps, or aching limbs.
In rare cases of the norovirus, seizures can occur. Symptoms normally last between 12-60 hours, although most people make a full recovery within one to two days. However, the diarrhoea may last slightly longer."
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