SENSITIVE DETECTION OF HUMAN CALICIVIRIDAE BY RT-PCR

A semi-nested reverse transcriptase-polymerase chain reaction (RT-PCR) was developed for the detection of human Caliciviridae. The method wa s evaluated on faecal samples from patients with gastroenteritis sent to the Norwegian National Institute of Public Health for routine diagn osis by direct electron microscopy (EM). Of 166 samples, 49 were found to contain Caliciviridae by EM, while 7 samples contained other virus es. A total of 74 samples was positive by PCR, including all the sampl es with EM detectable Caliciviridae, while specimens containing other agents were negative. Phylogenetic analysis of RNA sequences from 14 N orwegian samples indicated that the viruses present in Norway are even ly distributed when compared to sequences of human Caliciviridae from other countries. The PCR primers should therefore be useful for sample s from other regions. The phylogenetic analysis did not cluster viruse s with a calici-like morphology, but mingled them with sequences from Norwalk-like viruses, indicating that the two morphological types do n ot represent separate genogroups. (C) 1996 Wiley-Liss, Inc.