Molecular characterization of norovirus from acute gastroenteritis patients in Malaysia

Rotavirus and recently norovirus have been described as important and most common cause of acute gastroenteritis in children. The mode of transmission is fecal-oral. Diagnosis of both of these viruses can be made by rapid antigen detection of the viruses in stool specimens and strains can be further characterized by enzyme immunoassay or reverse transcriptase polymerase chain reaction. Stool specimens collected from various hospitals in Malaysia were examined for norovirus by both immunochromatography and reverse-transcription polymerase chain reaction techniques. Rotavirus antigen was screened by a commercially available latex agglutination test kit. Altogether, 168 stool samples were collected for both norovirus and rotavirus screening. Out of these, 77/168 (45.8%) were examined for rotavirus with 17/77 (22%) rotavirus antigen positive. Due to very small amount of fecal materials obtained in some cases, only 151/168 (89.8%) were sufficient for norovirus and 14/151 (9.3%) were positive for norovirus genogroup II (GII). This study highlights that rotavirus remains the main agent for acute gastroenteritis and identification for emerging norovirus among the children is becoming important for proper patient management.   Key words: Norovirus, rotavirus, immunochromatography, latex agglutination, RT-PCR, phylogenetic analysis.