Norovirus, computer illustration. Norovirus is a genus of RNA (ribonucleic acid) viruses (of the family Caliciviridae), which cause about half of all gastroenteritis cases around the world. The disease is characterised by nausea, vomiting, diarrhoea and abdominal pain. The diarrhoea results in fluid loss and dehydration, which may become life-threatening in the young, the elderly, and the immunocompromised if not treated promptly.
Three people at the American Red Cross’ Pasadena Evacuation Shelter have tested positive for norovirus, according to the Pasadena Public Health Department.
There are an additional 25 people at the shelter who have acute gastrointestinal illness.
“The spread of illness in congregate living situations, including shelters, is unfortunately common given the close quarters and communal spaces,'' the Pasadena Public Health Department wrote in a statement.
According to the Center for Disease Control, norovirus causes diarrhea and vomiting. It is contagious and symptoms also include stomach pain, fever, headache and body aches.
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An individual will usually experience symptoms between 12 and 48 hours after exposure. Illness typically lasts for one to three days but people can still be contagious after their symptoms have subsided.
Those experiencing symptoms at the shelter are being told to isolate immediately. People are being asked to wash their hands regularly.
