BackgroundGroup A rotaviruses are the most significant cause of acute gastroenteritis in children worldwide. Rotaviruses are shed in high numbers and dispersed widely throughout bodies of water in the environment. This represents a significant health hazard for humans, mainly due to the stability of the viruses during wastewater treatment processes. This study was conducted to evaluate the prevalence of rotaviruses, to determine G genotypes of circulating rotaviruses and to assess the efficiency of rotavirus removal in urban and hospital sewage treatment plants in Shiraz, Iran.Materials and methodsDuring the period from October 2010 to June 2011, a total of sixty sewage samples from urban and hospital sewage disposal systems were collected by Grab Sampling in Shiraz, Iran. All the samples were concentrated in pellet form and two-phase methods and then group A rotaviruses were investigated with enzyme immunoassays (EIA). Rotavirus-positive specimens were genotyped by the nested RT-PCR and by using different types of specific primers.ResultsIn total, rotaviruses were identified in 25% (15 cases) of sewage samples, representing 73.33% (11 cases) of influent and 26.67% (4 cases) of effluent systems. The frequency of rotavirus detection in autumn, winter and spring was 46.67%, 33.33% and 20%, respectively (P= 0.004). The most common circulating genotype was G1 (73.33%), followed by G1G4 (20%) and non-typeable (6.67%), respectively.ConclusionsThe high prevalence of rotaviruses in urban and hospital sewage systems highlights the importance of environmental surveillance as a tool to detect new genotypes and to investigate the epidemiology of rotaviruses circulating in the community.

BACKGROUND AND OBJECTIVESDifferent types of viruses are the leading cause of acute diarrhea among infants and young children worldwide. Epidemiological surveillance of viral agents is critical for the development of effective preventive measures, including vaccines. This study aimed to determine the prevalence of the four major enteropathogenic viruses—rotavirus, norovirus, adenovirus and astrovirus—in children over 7 years of age.DESIGN AND SETTINGA cross-sectional descriptive study conducted on stool specimens of children with acute gastroenteritis admitted to the Pediatrics Unit of 17 Shahrivar Hospital in Borazjan, Iran from October 2008 to September 2010.PATIENTS AND METHODSAcute gastroenteritis was defined as ≥3 loose watery stools per 24 hours. A total of 375 stool samples were collected from hospitalized children aged <7 years old with acute gastroenteritis. All samples were investigated by using enzyme-linked immunosorbent assay for the presence of viral antigens.RESULTSRotavirus was detected in 91 (24.3%) of the patients whereas the prevalence of norovirus, adenovirus and astrovirus was 12.5%, 5.1% and 2.4%, respectively. On average, 75.9% of children with viral diarrhea were younger than 2 years old (P=.023). All the strains of viral gastroenteritis studied peaked in the autumn, except for adenovirus which peaked in spring (P=.015). The most common clinical symptoms included diarrhea (92.2%), vomiting (68.7%), abdominal cramp (60.8%) and moderate dehydration (57.2%).CONCLUSIONSince nearly half of gastroenteritis cases (44.3%) were due to viral agents, testing for the viral antigens may guide the clinical approach to those patients with acute diarrhea particularly in the case of children less than 2 years old, and during cold seasons.