Applicability of microarray technique for the detection of noro- and astroviruses

Noroviruses and astroviruses are widespread viral agents causing gastroenteritis. Noroviruses are actually a diverse group of viruses. A new microarray-based detection method is presented for both noro- and astroviruses. This method enables simultaneous identification of genogroups and types of noro- and astroviruses. For pre-amplification, the monoplex- and multiplex-RT-PCR assays were applied to test sensitivity. The 202 specimens were used to determine the specificity, precision, and accuracy of the microarray. Stool samples representing 13 of norovirus GI and GII genotypes were assayed. The microarray detected all but one genotype. In a panel of 74 stool samples, 45 tested positive for norovirus by microarray, against 35 by a conventional PCR-method. In addition, microarray detected some double infections. In a panel of archival samples, astroviruses of genotype 4 frequently emerged in Finland from 1977 to 1997. This study demonstrates that microarray is useful for simultaneous monitoring of several viruses and their subtypes. Microarray provides a convenient tool for the detection of RNA viruses for which frequent changes in the panel of detection primers may be required.