Cause Of Acute Gastroenteritis Research Articles

Association between Norovirus and Rotavirus Infection and Histo-Blood Group Antigen Types in Vietnamese Children

Norovirus and rotavirus are the two most important causes of acute gastroenteritis in children worldwide. Both norovirus and rotavirus recognize human histo-blood group antigens (HBGAs), and multiple binding patterns for HBGAs have been reported. To explore the role of HBGAs in host susceptibility to norovirus and rotavirus, we conducted a cross-sectional study in children hospitalized with diarrhea in northern Vietnam from September 2010 through September 2012. Of 260 children with paired stool and saliva samples, 158 (61%) were classified as HBGA secretors (Lea-b+), 31 (12%) were nonsecretors (Lea+b-), and 71 (27%) were partial secretors (Lea+b+). Norovirus was detected in 50 patients (19%), with viral genotypes GII.3 (n=28) and GII.4 (n=22) being the most common. All children infected with norovirus strains of genotype GII.4 were either HBGA secretors or partial secretors. Of the 28 GII.3 cases, 12 involved HBGA secretors, 11 partial secretors, and 5 nonsecretors. A total of 85 children tested positive for rotavirus, 74 of whom were infected with genotype P[8], 5 with P[4], and 6 with P[6]; all were HBGA secretors or partial secretors. This is the first epidemiological study demonstrating in a population that HBGA phenotype is a key susceptibility factor for both norovirus and rotavirus infections in children.

ENTERIC PATHOGENS OF DOGS AND CATS WITH PUBLIC HEALTH IMPLICATIONS

Dogs and cats play an important role in modern soci ety, enhancing the psychological and physiological well-being of many people. However, there are well- documented health risks associated with human animal interactions. More specifically, enteric pat hogens of zoonotic risk which are transmitted by fe ces of dogs and cats can be grouped as follows: (a) Par asites such as Toxocara canis , T. cati , Ancylostoma sp, Uncinaria sp, Strongyloides stercoralis , Echinococcus granulosus , E. multilocularis and Dipylidium caninum (b) Protozoa including Toxoplasma gondii, Giardia duodenalis and Cryptosporidium spp. (c) Bacteria of the genera Clostridium , Campylobacter, Salmonella, Escherichia, Yersinia and Helicobacter and (d) Viruses mainly Rotaviruses and Coronaviruses . Among them, Salmonella, Campylobacter, Rotaviruses , Toxoplasma gondii, Echinococcus have been reported to be of considerable importanc e for many countries including Greece. Even though offici al records of the cases in humans and livestock in Greece continuously decline, cystic echinococcosis is considered to be a serious problem for public health and livestock economy. Regarding other paras ites, the overall prevalence of parasitism was 26% in owned shepherd and hunting dogs examined in Serres. Furthermore, seroepidemiological studies revealed the presence of antibodies against T. gondii in a considerable percentage of hospitalized child ren. Rotaviruses were confirmed as a major cause of acute gastroent eritis in children. Finally, bacterial zoonotic enteropathogens were identified in a notab le number of pediatric cases. Most of these zoonose s are associated with the exposure of immunodeficient people or children to pets and/or conditions of po or hygiene. Studies on the presence of all these patho gens in animals are required to identify the extent of problem, to define control strategies and evaluate their effectiveness.

Norovirus gene expression and replication

Noroviruses are small, positive-sense RNA viruses within the family Caliciviridae, and are now accepted widely as a major cause of acute gastroenteritis in both developed and developing countries. Despite their impact, our understanding of the life cycle of noroviruses has lagged behind that of other RNA viruses due to the inability to culture human noroviruses (HuNVs). Our knowledge of norovirus biology has improved significantly over the past decade as a result of numerous technological advances. The use of a HuNV replicon, improved biochemical and cell-based assays, combined with the discovery of a murine norovirus capable of replication in cell culture, has improved greatly our understanding of the molecular mechanisms of norovirus genome translation and replication, as well as the interaction with host cell processes. In this review, the current state of knowledge of the intracellular life of noroviruses is discussed with particular emphasis on the mechanisms of viral gene expression and viral genome replication.

Development of VP6 Gene Specific Reverse Transcription(RT)-PCR Assay for Detectionof Avian Group D Rotavirus in Diarrheic Chickens

Development of VP6 Gene Specific Reverse Transcription(RT)-PCR Assay for Detection of Avian Group D Rotavirus in Diarrheic Chickens The group D rotavirus (RVD) is an evolving viral cause of acute gastroenteritis in avian species world over. Despite the increase in the frequency of avian RVD infections world over, isolates from Indian poultry have yet to be characterised. Paucity of epidemiological studies with unavailability of sensitive and rapid detection methods for RVD in poultry led to design of the present study, aiming at development and validation of a RT-PCR assay, targeting the conserved group specific region of VP6 gene of RVD, for virus detection purpose.

Rotavirus Group A Surveillance and Genotype Distribution in Russian Federation in Seasons 2012-2013

Rotavirus infection is one of the primary causes of acute gastroenteritis in industrialized countries and may be a cause of severe disease in children. Here we present the results of analysis of specific indicators which characterize the burden of rotavirus infection in Russia such as passive surveillance data for rotavirus gastroenteritis cases (RG), the proportion of outbreaks of rotavirus per calendar month and laboratory-based data of rotavirus infection occurrence in lethal cases involving children. Specific features of rotavirus [P]G genotypes distribution in different geographic regions of Russia from 2012 through 2013 are also provided.

Use of Population-based Surveillance to Determine the Incidence of Rotavirus Gastroenteritis in an Urban Slum and a Rural Setting in Kenya

Rotavirus gastroenteritis is a major cause of mortality among children <2 years of age. Disease burden data are important for introducing and sustaining new rotavirus vaccines in immunization programs. We analyzed population-based infectious disease surveillance data from 2007 to 2010 from Kenyan sites in rural and urban slum areas. Stool specimens were collected from patients of all ages presenting to study clinics with diarrheal disease and tested for rotavirus by enzyme immunoassay. Incidence rates were adjusted using data on healthcare utilization (from biweekly home visits) and proportion of stools collected at study clinics from patients meeting case definitions. Rotavirus was detected in 285 (9.0%) of 3174 stools tested, including 122 (11.9%) from children <5 years of age and 162 (7.6%) from participants ≥5 years of age. Adjusted incidence rates for infants were 13,419 and 12,135 per 100,000 person-years of observation in rural and urban areas, respectively. Adjusted incidence rates were high in adults across age ranges. The rates suggest that annually, among children <5 years of age, there are >54,500 cases of rotavirus-associated gastroenteritis in rural Nyanza Province and >16,750 cases in Nairobi urban slums. Community-based surveillance in urban and rural Kenya suggests that rotavirus plays an important role as a cause of acute gastroenteritis in adults, as well as in children. In addition to substantially preventing illness and complications from diarrheal disease in children, rotavirus infant immunization has the potential of indirectly preventing diarrheal disease in older children and adults, assuming children are the predominant sources of transmission.

Severe Acute Rotavirus Gastroenteritis in Children Less Than 5 Years in Southern Ghana

Rotavirus is a major cause of acute gastroenteritis (AGE) globally. Local data on disease burden will guide recommendations for rotavirus vaccination and monitoring impact of the intervention. Prospective surveillance for rotavirus gastroenteritis was conducted in 3 hospitals in southern Ghana during the period August 2006 to December 2011, as part of the African Rotavirus Surveillance Network. Clinical data and stool specimens were collected from children <5 years of age and hospitalized with AGE (defined as 3 or more watery stools for up to 7 days). Stool was tested for rotavirus by enzyme immunoassay and rotavirus genotype identified by reverse-transcriptase polymerase chain reaction. We tested 3044 stool samples from 3939 children. Rotavirus was detected in 45.6%, 51.3% and 48.5% of cases at the primary, secondary and tertiary care hospital, respectively. Both genders were equally affected; 75% (2954/3939) of the cohort were aged 3-18 months. Overall, rotavirus was detected in 49.4% (1504/3044) of cases, caused over 30% of AGE hospitalizations all year round and up to 70% of cases during peak seasons. Peak season occurred during cool dry months in 2008, 2010 and 2011 and the rainy season in 2009. Mortality from AGE occurred in 1.5% (45/3044) of cases and 48.9% (22/45) of these were rotavirus positive. Rotavirus causes significant morbidity and mortality in young Ghanaian children. As Ghana introduced rotavirus vaccination in the national immunization program in 2012, continued surveillance is required to monitor the impact of this intervention.

The Molecular Epidemiology of Circulating Group A Rotavirus in Gwangju Metropolitan City, Korea: 2008~2012

Group A rotaviruses are a major cause of acute gastroenteritis in young children worldwide. For the proper management of rotavirus infections, knowledge of the distribution of G and P genotypes including detection of emerging genotype is crucial. Therefore, the aim of this study is to describe epidemiological changes in rotavirus gastroenteritis in Gwangju metropolitan city, South Korea. Stool samples were collected from 14,314 patients with diarrhea, who visited hospitals in Gwangju from 2008 to 2012. Samples were screened for rotavirus with Enzyme-Linked Immunosorbent Assay(ELISA) method and rotavirus P (VP4), G (VP7) genotypes were determined by reverse-transcription polymerase chain reaction. And we performed nucleotide sequencing analysis. Among a total of 14,314 samples investigated 1,982 samples (13.8%) were ELISA positive. Genotyping of Rotavirus was performed using 526 rotavirus samples. The most prevalent circulating G genotype was G1 (40.5%), followed by G2 (27.6%), G3 (19.4%), G9 (9.7%), G4 (2.5%) and G12 (0.4%). The predominant type of P genotypes was P[8] (69.6%), followed by P[4] (27.8%) and P[6] (2.3%). In this study, 13 G-P combinations were detected. From 2008 to 2010, G1P[8] was the most prevalent, followed by G3P[8]. Whereas, 2011 and 2012, G2P[4] was the most common, followed by G1P[8]. Rotavirus gastroenteritis is a common disease associated with significant morbidity, mortality and economic burden. Ongoing rotavirus surveillance to understand the distribution of G and P genotypes will be critical for the development of effective prevention measurements.

Full-Genomic Analysis of a Human Norovirus Recombinant GII.12/13 Novel Strain Isolated from South Korea

Norovirus (NoV) genogroups I and II are frequently recognized as the main causes of acute gastroenteritis and outbreaks of non-bacterial foodborne diseases. Furthermore, variants and recombinant strains of this virus are continuously emerging worldwide. The aim of this study was to identify NoV strains and to investigate and characterize rare genotypes. Stool samples (n = 500) were collected from patients with symptoms of acute gastroenteritis in Korea between December 2004 and November 2007. For analysis of the samples, rapid genotype screening was performed using reverse transcriptase-polymerase chain reaction. Full sequencing, using a newly designed set of 12 primers, revealed GII-12/13 strain. The partial sequence of GII-12/13 strain was compared with published NoV (GII-1 - 14) sequences targeting RdRp and capsid regions using phylogenetic analysis with the SimPlot program, which could evaluate recombination breakpoints. SimPlot analysis was also performed with the strain GII-12/Gifu-96/JPN (AB045603) for the RdRp region and with GII-13/G5175B-83/AUS(DQ379714) for the capsid region. NoV was detected in 19 of the 500 stool samples (3.8%). Genogroup GII-4 was found most frequently (n = 9, 1.8%), followed by GII-3 (n = 4, 0.8%), GII-6 (n = 3, 0.6%), GI-6 (n = 2, 0.4%), and GII-12/13 (n = 1, 0.2%). Importantly, we identified a novel NoV recombinant strain, C9-439 (KF289337), indicating potential risks, which suggested that, recombination occurred in the region between open reading frames 1 and 2 of the GII-12/13 strain and that breakpoints occurred in the polymerase region.

The emergence and evolution of the novel epidemic norovirus GII.4 variant Sydney 2012

Norovirus is the leading cause of acute gastroenteritis with most infections caused by GII.4 variants. To understand the evolutionary processes that contribute to the emergence of GII.4 variants, we examined the molecular epidemiology of norovirus-associated acute gastroenteritis in Australia and New Zealand from 893 outbreaks between 2009 and 2012. Throughout the study GII.4 New Orleans 2009 was predominant; however, during 2012 it was replaced by an emergent GII.4 variant, Sydney 2012. An evolutionary analysis of capsid gene sequences was performed to determine the origins and selective pressures driving the emergence of these recently circulating GII.4 variants. This revealed that both New Orleans 2009 and Sydney 2012 share a common ancestor with GII.4 Apeldoorn 2007. Furthermore, pre-epidemic ancestral variants of each virus were identified up to two years before their pandemic emergence. Adaptive changes at known blockade epitopes in the viral capsid were also identified that likely contributed to their emergence.

Rapid Emergence of Novel GII.4 Sub-Lineages Noroviruses Associated with Outbreaks in Huzhou, China, 2008–2012

Infection caused by noroviruses (NoVs) is one of the most important causes of acute gastroenteritis in humans worldwide. To gain insight into the epidemiology of and genetic variation in NoV strains, stool samples collected from 18 outbreaks of acute gastroenteritis in Huzhou, China, between January 2008 and December 2012 were analyzed. Samples were tested for NoVs by real-time RT-PCR. Partial sequences of the RNA- dependent RNA polymerase (RdRp) and capsid gene of the positive samples were amplified by RT-PCR, and the PCR products were sequenced and used for phylogenetic analysis. NoVs were found to be responsible of 88.8% of all nonbacterial acute gastroenteritis outbreaks in Huzhou over the last 5 years. Genogroup II outbreaks largely predominated and represented 93% of all outbreaks. A variety of genotypes were found among genogroups I and II, including GI.4, GI.8, GII.4, and GII.b. Moreover, phylogenetic analyses identified two recombinant genotypes (polymerase/capsid): GI.2/GI.6 and GII.e/GII.4 2012 Sydney. GII.4 was predominant and involved in 8/10 typed outbreaks. During the study period, GII.4 NoV variants 2006b, New Orleans 2009, and Sydney 2012 were identified. This is the first report of the detection of GII.4 New Orleans 2009 variant, GII.e/GII.4 Sydney 2012 recombinant in outbreaks of acute gastroenteritis in China.

Molecular Evidence of Group D Rotavirus in Commercial Broiler Chicks in India

Group D rotavirus (RVD) is one of the evolving viral causes of acute gastroenteritis in avian species all over the world but its frequency in Indian poultry is not known. We report here the first sequence-confirmed RVD infection in 1–2 week old broiler chicks from northern India. Initial confirmation of type D rotavirus was done using polyacrylamide gel electrophoresis and VP6 gene based reverse-transcriptase-PCR (RT-PCR) for group D rotavirus, which produced a specific 742 bp amplicon in positive cases. The intestinal contents which showed presence of group D rotavirus strain were designated as RVD/Avian/India/PTN-14/2012/ GXP[X] and RVD/Avian/India/UKD-48/2012/GXP[X]. The comparative sequence analysis based on partial VP6 gene of type D rotavirus Indian strains revealed higher homology with the VP6 genes of the avian group D rotaviruses from Brazil, Germany, Netherlands, Bangladesh and UK, both at the nucleotide (87.2–89.6%) and amino acid (98.7–99.5%) levels. These two Indian avian RVD isolates clustered together, away from other Asian group D isolates from Bangladesh. The analysis of group specific VP6 protein showed amino acid changes at only two positions i.e. 228 and 384 when compared to the reference group D rotavirus strain (GenBank accession number: GU733448) confirming conserved nature of this protein. This seems to be the first sequence-confirmed detection of group D avian rotavirus in broiler chicks from India. The findings emphasise the importance of this virus in enteric infections of Indian poultry flocks. The study also emphasises the need for intensifying the epidemiological surveillance for group D rotaviruses in the near future.

Progress Towards the Prevention and Treatment of Norovirus Infections

Noroviruses are now recognized as the major cause of acute gastroenteritis in the developed world, yet our ability to prevent and control infection is limited. Recent work has highlighted that, while typically an acute infection in the population, immunocompromised patients often experience long-term infections that may last many years. This cohort of patients and those regularly exposed to infectious material, for example, care workers and others, would benefit greatly from the development of a vaccine or antiviral therapy. While a licensed vaccine or antiviral has yet to be developed, work over the past 10 years in this area has intensified and trials with a vaccine candidate have proven promising. Numerous antiviral targets and small molecule inhibitors that have efficacy in cell culture have now been identified; however, further studies in this area are required in order to make these suitable for clinical use.

Monitoring of Calicivirus among day-care children: Evidence of asymptomatic viral excretion and first report of GI.7 norovirus and GI.3 sapovirus in Brazil

Caliciviruses (Norovirus and Sapovirus) are important causes of acute gastroenteritis, with Norovirus (NoV) considered the leading cause of epidemic non-bacterial acute gastroenteritis; however, molecular and epidemiological data of the circulating Calicivirus (CV) strains among day-care children are still considered scarce. The role of asymptomatic CV excretion on viral transmission also remains poorly understood. The aim of the present study was to monitor the occurrence of NoV and Sapovirus (SaV) in a day-care center and to describe the molecular epidemiology of the circulating strains. Genomic sequencing and phylogenetic analysis of the capsid region were carried out in CV positive samples obtained from children younger than 5 years, with or without diarrhea, between October 2009 and October 2011. A total of 539 fecal samples were screened for CV. Forty-three (8%) were positive for NoV and 25 (4.6%) for SaV. Surprisingly, positivity rates for CV were significant in asymptomatic children, and virus circulation was detected in every month of the study. Great genomic diversity of CV was observed, and the circulating NoV strains were: GII.6, GII.2, GII.1, GI.7, GII.4, and GI.1. The SaV genotypes GI.1 and GI.3 were also detected. Five CV outbreaks caused by distinct viral strains were documented. This study provides an insight on the genetic diversity of CV in a day-care in Central West Brazil, highlighting the probable role of asymptomatic viral excretion and the significance of semi-closed settings in the dissemination of these agents.

A Systematic Review and Meta-Analysis of the Global Seasonality of Norovirus

BackgroundNoroviruses are the most common cause of acute gastroenteritis across all ages worldwide. These pathogens are generally understood to exhibit a wintertime seasonality, though a systematic assessment of seasonal patterns has not been conducted in the era of modern diagnostics.MethodsWe conducted a systematic review of the Pubmed Medline database for articles published between 1997 and 2011 to identify and extract data from articles reporting on monthly counts of norovirus. We conducted a descriptive analysis to document seasonal patterns of norovirus disease, and we also constructed multivariate linear models to identify factors associated with the strength of norovirus seasonality.ResultsThe searched identified 293 unique articles, yielding 38 case and 29 outbreak data series. Within these data series, 52.7% of cases and 41.2% of outbreaks occurred in winter months, and 78.9% of cases and 71.0% of outbreaks occurred in cool months. Both case and outbreak studies showed an earlier peak in season-year 2002-03, but not in season-year 2006-07, years when new genogroup II type 4 variants emerged. For outbreaks, norovirus season strength was positively associated with average rainfall in the wettest month, and inversely associated with crude birth rate in both bivariate and multivariate analyses. For cases, none of the covariates examined was associated with season strength. When case and outbreaks were combined, average rainfall in the wettest month was positively associated with season strength.ConclusionsNorovirus is a wintertime phenomenon, at least in the temperate northern hemisphere where most data are available. Our results point to possible associations of season strength with rain in the wettest month and crude birth rate.

Clinical relevance and genotypes of circulating noroviruses in northern Taiwan, 2006-2011

The incidence of noroviral gastroenteritis has increased dramatically in recent years, and norovirus (NoV) genogroup II.4 (GII.4) is associated with outbreaks worldwide. The NoV genotypes and their clinical relevance in children hospitalized with acute gastroenteritis between 2006 and 2011 in northern Taiwan were evaluated in this study. NoV sequences were amplified from 47 clinical specimens and phylogenetic analysis was performed. Based on noroviral capsid protein (VP1) and RNA dependent RNA polymerase (RdRp) phylogeny, circulating NoV could be divided into GII.2, GII.3, GII.12, and GII.4 and GII.16, GII.12, GII.g, and GII.4; respectively. The GII.4 subtype was predominant and could be divided further into the 2004 (Hunter), 2006b, and 2010 (New Orleans) subtypes. Regarding clinical manifestations, convulsive disorder occurred only in cases caused by NoV GII.4 2006b. Patients affected by NoV GII.4 2006b presented with a higher frequency of diarrhea (P = 0.0204), longer duration of diarrhea (P = 0.0215), more frequent hypoglycemia (P = 0.038), and electrolyte imbalance (P = 0.0487) than acute gastroenteritis caused by NoV GII.4 2010. Structural analysis showed that the amino acid changes in viral VP1 between GII.4 2006b and 2010 subtype were located mainly in the protruding domain 2 (P2 domain). In conclusion, the NoV GII.4 variants 2006b and 2010 were the main causes of acute gastroenteritis in hospitalized children in northern Taiwan during 2006-2011. The clinical presentations and structural changes in VP1 of the two NoV GII.4 variants should be evaluated in the future.

Inactivation of Feline Calicivirus by Chlorine Dioxide Gas-generating Gel

Noroviruses are one of the most important causes of acute gastroenteritis throughout the world. The aim of this study is to evaluate the efficacy of a chlorine dioxide gas-generating gel (ClO2 gel, 60 g) against feline calicivirus (FCV), a norovirus surrogate, in the wet state on glass dishes in a test sink (43 cm long, 75 cm wide, and 29 cm deep). The ClO2 gel permits sustained release of gaseous ClO2 (1.7 mg/h at 25°C), and was placed in one corner of the test sink. The glass dishes containing FCV suspension were placed at three positions in the test sink. We demonstrated that FCV was inactivated within 5h (>2 or >3 log10 reductions at three positions, n=20) in the test sink where the ClO2 gel was placed. These small quantities of ClO2 gel might be a useful tool for reducing the risk of infection by norovirus in wet environments such as kitchens and bathrooms under optimal condition.

Failure of propagation of human norovirus in intestinal epithelial cells with microvilli grown in three-dimensional cultures

Human noroviruses (HuNoVs) are a leading cause of acute gastroenteritis. Establishment of a cell culture system for in vitro HuNoV growth remains challenging. Replication of HuNoVs in human intestinal cell lines (INT-407 and Caco-2) that differentiate to produce microvilli in rotation wall vessel (RWV) three-dimensional cultures has been reported (Straub et al. in Emerg Infect Dis 13:396-403, 2007; J Water Health 9:225-240, 2011, and Water Sci Technol 67:863-868, 2013). We used a similar RWV system, intestinal cell lines, and the same (Genogroup [G] I.1) plus additional (GII.4 and GII.12) HuNoV strains to test the system's reproducibility and to expand the earlier findings. Apical microvilli were observed on the surface of both cell lines by light and electron microscopy. However, none of the cell types tested resulted in productive viral replication of any of the HuNoV strains, as confirmed by plateau or declining viral RNA titers in the supernatants and cell lysates of HuNoV-infected cells, determined by real-time reverse transcription PCR. These trends were the same when culture supplements were added that have been reported to be effective for replication of other fastidious enteric viruses in vitro. Additionally, by confocal microscopy and orthoslice analysis, viral capsid proteins were mainly observed above the actin filament signals, which suggested that the majority of viral antigens were on the cell surface. We conclude that even intestinal cells displaying microvilli were not sufficient to support HuNoV replication under the conditions tested.

Physicochemical analysis of rotavirus segment 11 supports a ‘modified panhandle’ structure and not the predicted alternative tRNA-like structure (TRLS)

Rotaviruses are a major cause of acute gastroenteritis, which is often fatal in infants. The viral genome consists of 11 double-stranded RNA segments, but little is known about their cis-acting sequences and structural elements. Covariation studies and phylogenetic analysis exploring the potential structure of RNA11 of rotaviruses suggested that, besides the previously predicted “modified panhandle” structure, the 5’ and 3’ termini of one of the isoforms of the bovine rotavirus UKtc strain may interact to form a tRNA-like structure (TRLS). Such TRLSs have been identified in RNAs of plant viruses, where they are important for enhancing replication and packaging. However, using tRNA mimicry assays (in vitro aminoacylation and 3’- adenylation), we found no biochemical evidence for tRNA-like functions of RNA11. Capping, synthetic 3’ adenylation and manipulation of divalent cation concentrations did not change this finding. NMR studies on a 5’- and 3’-deletion construct of RNA11 containing the putative intra-strand complementary sequences supported a predominant panhandle structure and did not conform to a cloverleaf fold despite the strong evidence for a predicted structure in this conserved region of the viral RNA. Additional viral or cellular factors may be needed to stabilise it into a form with tRNA-like properties.

Frequency of Rotavirus and Adenovirus Gastroenteritis Among Children in Shiraz, Iran

BackgroundViral pathogens are the main cause of acute gastroenteritis in developed and developing countries. Rotavirus and adenovirus are the two important agents associated with hospitalization for diarrhea especially in children. Limitation and control of diarrhea as a costly disease must be considered in national health programs.ObjectivesEpidemiological studies on viral diarrhea and collecting data for rotavirus and adenovirus prevalence, as two important viral agents of gastroenteritis, are valuable for planning of a prospective program.Materials and Methods827 stool samples of pediatrics patients with gastroenteritis who were admitted to Dastgheib Hospital, Shiraz, Iran, from September 2008 to February 2010 were tested for presence of rotavirus and adenovirus using the EIA method. A demographic and clinical study was performed to determine the relationship between viral infection and clinical outcomes of patients.ResultsRotavirus was identified in 347 patients out of 827 (42%), adenovirus was detected in 76 (9%) of samples and 34 (4%) of patients had rotavirus-adenovirus co-infection. Diarrhea was the most common symptom in viral infected patients.ConclusionsGiven the non-specific symptoms of these viruses and the high prevalence of viral diarrhea in our region, more laboratories should be equipped for virus detection and vaccination might be considered as a prevention strategy.