Comparison of two different real time PCR assays and chemistry for detection of norovirus genogroup II. Method of choice? Noroviruses (Caliciviridae) are one of the main cause of acute non-bacterial gastroenteritis in humans. Noroviruses can not be propagated in cell cultures. Thus Real Time PCR molecular methods for caliciviral detection have been recently introduced. The aim of the study was to compare two different Real Time PCR assays for detection of norovirus strains (genogroup II) and the comparison between different RT-PCR reagents and Real Time PCR instruments was made.