Medical Q&As

Winter vomiting bug - immunity?

I got the vomiting virus before last Christmas. Is it possible to get it again or am I immune?

The so-called “winter vomiting bug” is a viral infection. The causative agents are known by a number of names including Norwalk-like viruses, SRSVs (small round structured viruses) and caliciviruses. Norwalk-like viruses cause an acute gastroenteritis and are the commonest cause of viral gastroenteritis epidemics. Symptoms include vomiting and diarrhoea. The symptoms take 12 to 48 hours to develop, and last for about 2 days. Outbreaks occur most frequently in hospitals and nursing homes due to person to person spread. Long term immunity does not follow from exposure to the Norwalk-like virus even if antibodies are present in the blood. It is thought that immunity against the winter vomiting bug lasts 3 months approximately therefore you could acquire the infection again this winter if you were re-exposed.