It may now be possible to develop vaccines to treat stomach flu for researchers at the University of North Carolina have found that the virus responsible the disease genetically mutates itself, similar to the virus that causes influenza.
The symptoms of Noroviruses, commonly called 'stomach flu' include 72 hours of vomiting and diarrhoea and could sometimes lead to death among the elderly and infants.
"One of the mysteries of medicine has been why do they keep infecting people when you'd think we'd be developing immunity," said Lisa Lindesmith, one of the lead authors of the study.
After examining the relationship between the sequences of genes encoding the GII.4 norovirus strains that have been isolated over the past 20 years they found that the virus evolved irregularly.
"What we've found is that the GII.4 arm [of the noroviruses] keeps changing. Whenever we're seeing big outbreaks of norovirus, we're also seeing genetic changes in the virus," she added.
"Noroviruses are very contagious. It may only take one or two viral particles to become infected.
"Good hand washing is critical when the virus is present. A vaccine may someday have an important role, too, especially among the elderly and other people particularly vulnerable to the effects of the illness," she said.