In Virginia, the number of outbreaks is about 20 percent higher than during the same period last year, health officials said.
responsible for most of viral gastroenteritis outbreaks
Genogroup II noroviruses are non enveloped and single strand RNA viruses. These human enteric viruses are responsible for most of viral gastroenteritis outbreaks. They are pathogenic for all age groups of the population. These viruses are very infectious; one to ten viral particles are sufficient to get sick.
Their mode of transmission is the feco-oral route. After excretion in human stool, due to their structural properties, noroviruses can resist to different physical and chemical treatment. Adsorbed on particles, they can survive in different types of environment for a long period. Food samples can be contaminated via food handlers or by the environment. Due to their structural properties, norovirus can survive to different food processes. The consumption of contaminated food can lead to human outbreak.
methods of choice for NoV detection
There is no cell culture available for the multiplication of human noroviruses. The detection by ELISA is not recommended due to norovirus genetic diversity and its lack of sensitivity. Molecular techniques (real time RT-PCR) are the methods of choice for NoV detection after extraction and viral RNA purification from the sample.