A molecular study on the prevalence and coinfections of Rotavirus, Norovirus, Astrovirus and Adenovirus in children with gastroenteritis.

Background: Viral gastroenteritides are among the causes of higher morbidity and mortality in the childhood period, especially in infants. Although viral-induced diarrheal diseases are important problems in Erzurum, there have been no studies on the molecular prevalence of viral gastroenteritis agents in this region's children. The aim of the prospective study is to determine the molecular prevalence of the most commonly seen viral etiologic agents and their coinfection rates in children under 5 years of age with gastroenteritis in Erzurum, Turkey.
Methods: Stool samples from 375 children between 0 and 5 years of age who suffered from acute diarrhea were investigated for the presence of Rotavirus, Norovirus, Astrovirus and Adenovirus by reverse transcriptase polymerase chain reaction, followed by conventional PCR techniques. The presence of Rotavirus, Norovirus, Astrovirus and Adenovirus in the specimens was detected by amplification of the VP6, RdRp, ORF-1b and Hexon regions, respectively. Stool samples were also investigated non-viral enteropathogens by conventional techniques.
Results: At least one viral pathogen was detected in 59.2% of the stool samples. Rotavirus was the most frequently observed agent (32.3%), followed by Norovirus (20.3%), Adenovirus (9.6%) and Astrovirus (5.6%). All specimens were negative for bacterial pathogens. Twenty seven (7.2%) specimens were positive for intestinal helminths and protozoan. A total of 39 coinfection (10.4%) including 38 dual and 1 triple were detected. The most frequent coinfections were observed between Norovirus plus Rotavirus and Norovirus plus Adenovirus.
Conclusions: Single infections or coinfections of the enteropathogenic viruses occur at a significant rate in Erzurum's children. This study draws attention to the necessity of taking account of multiple viral infections in studies on combined vaccines and the treatment of gastroenteritis.