Viral etiology of acute infantile diarrhea in autumn and winter in Shenzhen

Objective To investigate the prevalence of rotavims, norovirns, astrovirus and enteric adenovirus among the acute infantile diarrhea in autumn and winter in Shenzhen and compare enzyme-linked immunosorbent assay (EIJSA)with polymerase chain reactions (PCR) in detecting the four acute gastrointestinal viruses. Methods Fecal specimens were collected from 192 outpatients under 3 years old with acute diarrhea from October 2007 to February 2008 in Sbenshen. ELISA was used to detect the viral antigens and PCR was used to detect nucleic acids of four viruses. The PCR products were purified and sequenced. Results Among 192 fecal specimens, 81.3% were identified for at least one virus by either of ELISA or PCR, which included 119 for rotavirus (62.0%), 34 for norovirus (17.7%), 32 for enteric adenovirus (16.7%), 6 for astrovirus (3.1%),and 32 for mixed infections(16.7%). The positive rate of ELISA and PCR were 52.6% and 50.5% for rotavirus (χ2=0.4, P>0.05), 8.3% and 12.0% for norovirus (χ2=1.24, P>0.05), 7.3% and 11.5% for enteric adenovirus (χ2=1.75, P>0.05), and 1.6% and 2.1% for astrovirus (χ2=0,P>0.05). ELISA and PCR had no significant difference for detecting four viruses. These two methods showed good correlation with each other for detection of rotavirus with a Kappa value of 0.58 and poor agreement for norovirus, enteric adenovirus and astrovirus with a Kappa value of 0.18, 0.15 and 0.27, respectively. Conclusions RV is the dominant etiological agent of infantile diarrhea in Shenzhen, followed by norovirus and adenovirns. The high rate of mixed viral infection brings clinical concern. ELISA combined with PCR improve the diagnostic sensitivity for norovirus, enteric adenovirns and astrovirus. Key words: Diarrhea;  infantile;  Virus diseases;  Enzyme-linked immunosorbent assay;  Polymerase chain reaction