Winter Epidemic of Viral Gastroenteritis

Norovirus is one of the frequent causes of a seasonal rise of viral gastroenteritis in Hong Kong during September through December. Norovirus is occasionally mentioned as “winter vomiting disease”. 
Two different epidemiological patterns are winter vomiting disease most prevalent. The first type of winter vomiting disease is transmitted and mainly affects adults, and frequently associated with eating up undercooked bivalve shellfish like raw oysters. The second type is spreads person-to-person. After the incubation period is completed, a vomiting incident is started followed by an acute gastroenteritis among patients. This type is more commonly found among attendees and residents of schools and nursing homes.
Some viruses like rotavirus, enteric adenoviruses, astrovirus, and sapovirus have been proved to be as agents of acute viral gastroenteritis. These gastroenteritis agents are frequently cause intermittent diarrheal infections and are fewer connections with epidemics. Rotavirus is the most common reason of acute childhood gastroenteritis especially in the winter months of December and January. Rotavirus is the most common reason of acute childhood gastroenteritis in nursery outbreaks especially in the winter months of December and January. These agents are typically self-limiting by giving immediate supportive treatments like Rehydration.
For the purpose of laboratory examination of acute gastroenteritis, the optimal specimen of diarrheal stool is obtained during the severe stage of illness, when the viral agent is shed in large amounts.
To examine the presence of above viral agents, electron microscopy can be used to catch-all the agents. However, this technique is not useful if specimens of formed stool or rectal swabs are examined at late stages.