Norovirus has been called Norwalk-like viruses before. It will infect stomach and intestines to cause gastroenteritis.
Its clinical manifestation is like feeling sick, vomiting and stomach spasmodic diarrhea. Some cases said that they had headache, fever, shiver and muscle ache. The symptoms will last 1 to 2 days. The patient generally feels serious and vomits violently for several times in a day. The course of it is based on individual and generally lasts 2-3 days. There is no sequela after recovery. Children, the old and the weak are easily to be infected.
At present there is no evidence to show that the infected person will become long-term virus carrier, however, virus can be found in waste and vomit of them in 2 weeks after the course of it.
Norovirus can infect in following ways: eating food polluted by it or having drink polluted by it, contacting hands with mouth after hand¡¯s touch with things or surfaces polluted by Norovirus and direct contact with infected person (like looking after patients, having dinner or share tableware with them).
Food and drinks can be easily infected by Norovirus because virus is so small and less than 100 viruses absorbed will cause diseases. Food can be polluted by polluted hands, surface of tings polluted by vomit or waste or flying particles of vomit nearby. Though it is difficult to propagate outside human body, it will cause diseases while existing in food or water.
Norovirus gastroenteritis always breaks out in hotel, yacht, children¡¯s room, hospital, school, feast hall, summer camp and family gathering dinner. It is estimated that half of breaking-out the disease interrelated with food were caused by Norovirus.
A ma will be infected with Norovirus many times in his life because there are so many types of Norovirus that one cannot prevent infected with other type by being infected one of them. There is lack of cross protection after natural infection which is the key reason that it is difficult to develop Norovirus vaccine.
Be on your guard on Norovirus diarrhea. Keeping far away from raw food and washing hands regularly are the best way.
