Frequency of rotavirus and adenovirus gastroenteritis among children in shiraz, iran

Circulating rotavirus strains in children with acute gastroenteritis in Iran, 1986 to 2023 and their genetic/antigenic divergence compared to approved vaccines strains (Rotarix, RotaTeq, ROTAVAC, ROTASIIL) before mass vaccination: Clues for vaccination policy makers

In the present study, first, rotaviruses that caused acute gastroenteritis in children under five years of age during the time before the vaccine was introduced in Iran (1986 to 2023) are reviewed. Subsequently, the antigenic epitopes of the VP7 and VP4/VP8 proteins in circulating rotavirus strains in Iran and that of the vaccine strains were compared and their genetic differences in histo-blood group antigens (HBGAs) and the potential impact on rotavirus infection susceptibility and vaccine efficacy were discussed. Overall data indicate that rotavirus was estimated in about 38.1 % of samples tested. The most common genotypes or combinations were G1 and P[8], or G1P[8]. From 2015 to 2023, there was a decline in the prevalence of G1P[8], with intermittent peaks of genotypes G3P[8] and G9P[8]. The analyses suggested that the monovalent Rotarix vaccine or monovalent vaccines containing the G1P[8] component might be proper in areas with a similar rotavirus genotype pattern and genetic background as the Iranian population where the G1P[8] strain is the most predominant and has the ability to bind to HBGA secretors. While the same concept can be applied to RotaTeq and RotasIIL vaccines, their complex vaccine technology, which involves reassortment, makes them less of a priority. The ROTASIIL vaccine, despite not having the VP4 arm (P[5]) as a suitable protection option, has previously shown the ability to neutralize not only G9-lineage I strains but also other G9-lineages at high titers. Thus, vaccination with the ROTASIIL vaccine may be more effective in Iran compared to RotaTeq. However, considering the rotavirus genotypic pattern, ROTAVAC might not be a good choice for Iran. Overall, the findings of this study provide valuable insights into the prevalence of rotavirus strains and the potential effectiveness of different vaccines in the Iranian and similar populations.

Molecular Prevalence and Genotype Distribution of Human Adenovirus in Iranian Children with Gastroenteritis

OBJECTIVE

We determined the molecular prevalence and genotype distribution of human adenovirus (HAdV) among children under five years of age with gastroenteritis in Iran.

METHODS

One hundred stool samples from children hospitalized were tested by PCR for adenovirus, and some of the positive samples were sequenced to determine the specific genotype.

RESULTS

HAdV DNA was found in 15 samples (15%). The highest and the lowest prevalence of HAdV was observed in the age groups 24-60 months (n = 6; 40%) and 7-12 months (n = 2; 13.3%), respectively (p = 0.01). Nine HAdV-positive samples were sequenced, of which four isolates were HAdV type 2 and five isolates were HAdV type 41.

CONCLUSION

HAdV was most common in the 24-60-month-old children. Of the samples sequenced, we found only types 2 and 41. Our results show that in addition to HAdV types 40 and 41, HAdV type 2 may also play a role in causing gastroenteritis in children.

Molecular epidemiology, genetic diversity, and vaccine availability of viral acute gastroenteritis in the middle East and North Africa (MENA) region

Acute gastroenteritis is the cause of considerable mortality and morbidity worldwide, particularly among children under five years in underdeveloped countries. Most acute gastroenteritis (AGE) cases are attributed to viral etiologies, including rotavirus, norovirus, adenovirus, astrovirus, and sapovirus. This paper aimed to determine the prevalence rate of different viral etiologies of AGE in the Middle East and North Africa (MENA) region. Moreover, this paper explored rotavirus phylogenetic relatedness, compared VP7 and VP4 antigenic regions of rotavirus with vaccine strains, and explored the availability of vaccines in the MENA region. The literature search identified 160 studies from 18 countries from 1980 to 2019. The overall prevalence of rotavirus, norovirus, adenovirus, astrovirus, and sapovirus were 29.8 %, 13.9 %, 6.3 %, 3.5 %, and 3.2 % of tested samples, respectively. The most common rotavirus genotype combinations in the MENA region were G1P[8], G9P[9], and G2P[4], whereas GII.4 was the predominant norovirus genotype all of which were reported in almost all the studies with genotyping data. The comparison of VP7 and VP4 between circulating rotavirus in the MENA region and vaccine strains has revealed discrete divergent regions, including the neutralizing epitopes. Rotavirus vaccine was introduced to most of the countries of the MENA region; however, only a few studies have assessed the effectiveness of vaccine introduction. This paper provides a comprehensive update on the prevalence of the different viral agents of AGE in the MENA region.

Infection with adenovirus, rotavirus, and coinfection among hospitalized children with gastroenteritis in an Egyptian university hospital

Acute gastroenteritis is the main cause of mortality and morbidity in children worldwide. Studies stated that rotavirus and human adenovirus (HAdV) are common causes of nonbacterial gastroenteritis in children aged 0-5 years. The aim of this study was to determine the prevalence and the distribution of rotavirus, HAdV, and coinfections among hospitalized children with gastroenteritis below 7 years old and determine the prevalence of enteric HAdV among all HAdV gastroenteritis. The study was conducted on 150 children below 7 years old. Antigen detection for rotavirus and HAdV by ELISA and determination of enteric HAdV (serotype 40 and 41) by nested PCR and restriction endonucleases study were performed. Detection of rotavirus and HAdV antigens in 150 stool specimens from patients with gastroenteritis were 58% (87), 6.7% (10), and 8% (12) positive for rotavirus, HAdV, and coinfection, respectively. Out of 22 HAdV antigen-positive cases, 15 cases were positive by PCR for enteric HAdV, with the prevalence rate of enteric HAdV gastroenteritis among all HAdV gastroenteritis cases of 68%, a serotyping study by PCR detected serotype 40 in 46.7% of cases (7/15) and serotype 41 in 53.3% of cases (8/15) with no statistically significant difference between them. The study confirmed that rotavirus and HAdV are prevalent etiological agents of diarrhea in children below the school-age group, highlighting the necessity of the rotavirus vaccine in addition to the obligatory schedule of vaccines in Egypt. Also, it determined that the enteric HAdV gastroenteritis prevalence rate was 68% among all HAdV gastroenteritis.

Nonpharmaceutical interventions against the COVID-19 pandemic significantly decreased the spread of enterovirus in children

BACKGROUND

Precise prevention and control measures have been adopted to impede the transmission of COVID-19 in China. This study was performed to investigate the effect of protective measures on gastrointestinal infection in children during the COVID-19 pandemic.

METHODS

The data on the rotavirus and adenovirus antigen tests were collected in outpatient children due to gastroenteritis from January 1, 2019, to December 31, 2020, at the Children's Hospital of Zhejiang University School of Medicine. According to age and month distribution, the positive number and rate of rotavirus and adenovirus in 2020 were compared with 2019.

RESULTS

A 3.8-fold and 4-fold reduction in the number of rotavirus- and adenovirus-positive patients in 2020 were found, respectively. The overall positive rate of rotavirus and adenovirus infection was drastically decreased in 2020 (rotavirus 2020: 18.18% vs 2019: 9.75%, P < 0.001; adenovirus 2020: 3.13% vs 2019: 1.58%, P < 0.001). The proportions of rotavirus and adenovirus in all age groups in 2020 decreased compared with those in 2019. The highest frequency of rotavirus infection occurred among children aged 1-3 years both in 2019 and 2020 (2019: 27.95% vs 2020: 17.19%, P < 0.001), while adenovirus infection was detected in children aged 3-5 years, which had the highest percent positivity (2019: 8.19% vs 2020: 4.46%; P < 0.001). An obvious peak prevalence of rotavirus incidence was found during December-April, and the percent positivity of rotavirus significantly decreased in 2020 (December 2019: 24.26% vs 2020: 8.44%, P < 0.001; January 2019: 40.67% vs 2020: 38.18%, P < 0.05; February 2019: 40.73% vs 2020: 15.04%, P < 0.001; March 2019: 31.47% vs 2020: 7.88%, P < 0.001; April 2019: 15.52% vs 2020: 4.78%, P < 0.001). The positive rate of adenovirus distributed throughout 2019 was 1.91%-4.86%, while the percent positivity during 2020 in the same period was much lower (0.00%-3.58%).

CONCLUSIONS

Our results confirmed that the preventive and control measures adopted during the COVID-19 pandemic and the collateral benefit of these interventions have significantly decreased the transmission of rotavirus or adenovirus. This article is protected by copyright. All rights reserved.

A Pooled Analysis of Sex Differences in Rotaviral Enteritis Incidence Rates in Three Countries Over Different Time Periods

Background: Sex differences in incidence rates (IRs) of infectious diseases could provide clues to the mechanisms of infection. The results of studies on sex differences in the incidence of rotaviral enteritis have been inconsistent.

Methods: We carried out a pooled analysis of sex differences in IRs for rotaviral enteritis in three countries for a period of 7–22 years. Male-to-female incidence rate ratios (IRRs) were computed by age group, country, and years of reporting. A meta-analytic methodology was used to combine IRRs. Metaregression was performed to evaluate the contribution of age group, country, and years of reporting to the IRR.

Results: Significantly higher IRs in males were found in the age groups 0–4, 5–9, and 10–14 years, with pooled IRRs (with 95% confidence intervals [CIs]) of 1.12 (1.09–1.14), 1.07 (1.05–1.09), and 1.13 (1.05–1.21), respectively. In adults, the sex differences were reversed with higher rates in females. The pooled male-to-female IRRs (with 95% CIs) were 0.66 (0.64–0.68), 0.78 (0.72–0.85), and 0.78 (0.72–0.84) for the age groups 15–44, 45–64, and 65+ years, respectively. Metaregression results demonstrated that age is responsible for much of the variation in IRRs.

Conclusions: The higher rotaviral enteritis IRs in males at a very early age suggest that sex-related factors unrelated to exposure may play a role. The higher IRs in adult females could result, at least partly, from behavioral and occupational factors.

Prevalence of enteric adenovirus and co-infection with rotavirus in children under 15 years of age with gastroenteritis in Qom, Iran

AIM

The current study is the first performed in Qom to determine the prevalence of adenovirus and co-infections with rotavirus in children aged <15 years with gastroenteritis symptoms.

BACKGROUND

Gastroenteritis-associated viral infections are a cause of death among young children worldwide, especially in developing countries. The Adenovirus species F (40 and 41) are responsible for a range of acute diarrhea cases among infants and children.

METHODS

Over a period of 9 months, a total of 130 children suffering from intestinal problems who referred to the infectious ward of Children's Hospital were enrolled in the current study. After clinical examination and collection of demographic information, fecal samples were obtained from the patients. Viral genomes were extracted with a commercial kit and amplified and typed by adenovirus-specific PCR assay. Adenovirus-positive samples were also evaluated for co-infection with rotavirus.

RESULTS

Patients had a mean±SD age of 2.66±2.72 years; 63.1% of patients were male and 36.9% were female. Adenovirus infection was identified in 23 cases (17.7%), 21 (91.0%) and 2 (9.0%) of which were type 41 and type 40, respectively. Fever was the most common clinical manifestation among adenovirus-positive patients. No significant difference was observed between adenovirus infection and clinical symptoms, seasonal pattern, or serum laboratory results. Co-infection was found in only 5 cases (21.7%).

CONCLUSION

This study was the first to demonstrate adenovirus infection with a relatively high prevalence among children, especially infants, in Qom. The findings further revealed co-infection with rotavirus, indicating a health problem in this region.

Low Frequency of Adenovirus, Rotavirus, and Norovirus in Pediatric Diarrheal Samples from Central Iran

Background: Acute viral gastroenteritis is a disorder that affects children globally but mostly in developing countries. Adenoviruses, rotaviruses, and noroviruses are the leading viral causes of childhood gastroenteritis. Objectives: This study is the first to investigate the frequency of these viruses in diarrheal samples from pediatric patients living in central Iran. Methods: A total of 173 samples of pediatric diarrhea, from May 2015 to May 2016, were included in this descriptive cross-sectional study. The samples were analyzed using in-house developed PCR and reverse transcription (RT)-PCR methods to investigate the frequency of adenoviruses, rotaviruses, and noroviruses. Results: Out of 173 samples of pediatric diarrhea, eight were shown to contain enteric viruses (4.6%): (1) four with adenoviruses (2.3%); (2) three with rotaviruses (1.7%); and (3) one with a genogroup II norovirus (0.6%). Most of the positive samples were obtained from children under the age of seven. The most common additional clinical symptoms in pediatric patients with viral agents were fever, vomiting, and abdominal pain. Conclusions: In central Iran, adenoviruses and rotaviruses were rarely found as agents responsible for gastroenteritis. Although viral gastroenteritis in this area had less frequency than bacterial gastroenteritis, we need to monitor all enteropathogenic agents for longer periods to understand better real endemicity and the possibility of unexpected viral enteritis outbreaks.

Epidemiological, molecular, and clinical features of rotavirus infections among pediatrics in Qatar

Acute gastroenteritis (AGE) remains a major cause of diarrhea in developing and developed countries. Rotavirus (RV) is a leading cause of severe pediatric diarrhea worldwide. Here we report on the prevalence of circulating genotypes in association with demographics and clinical manifestations outcomes in Qatar. A total of 231 RV-positive fecal samples were collected from children suffering from AGE during 3 years study period between June 2016 and June 2019. The age of the subjects ranged between 2 months and 14 years (median of 16 months). The VP4 and VP7 were amplified and sequenced. Phylogenetic analyses were performed using MEGA7.0. Pearson's chi-squared test was used to determine significant differences for comparisons of general categorical variables. RV infections were most common in children between 1 and 3 years of age (49%), followed by those < 1 year and > 3 years of age (33% and 28%, respectively). RV infections were more frequent in males than females, with a ratio of 1.4:1. RV infections occurred throughout the year, with a noticeable increase in summer (42.8%) and a drop in winter (20.1%). RV genotypes G3P[8] (30.8%), G2P[8] (12.3%), G4P[8] (11.7%), and G1P[8] (10.4%) were the common genotypes during the study period. The G3P[8] strain detected in our study revealed similarities to the equine-like G3P[8] (10.3%; 24/231) (KT988229.1), Wa-like genomic constellation (9%; 21/231) (MF563894.1), and DS-1-like strains (6.4%; 15/231) (LC386081.1). Based on the Vesikari score system, severe clinical illness including diarrhea and vomiting (average frequency: 4 to 5 times/day) was recorded for G3P[8] group, followed by G9P[8], G4P[8], and G1P[8]. Higher incidence for G3P[8], G2P[8], G4P[8], and G1P[8] were reported in Qatari subjects compared to other nationalities. The multinational status of a small country explains the wide diversity of circulating RV genotypes in Qatar. The highest prevalence and severe illnesses were recorded to G3P[8], which is different from other surrounding countries/global levels.

Prevalence of astrovirus, adenovirus, and sapovirus infections among Iranian children with acute gastroenteritis

AIM

This study aimed to determine the prevalence of Human Astroviruses (HAstVs), enteric Adenoviruses (HAdVs), and Sapoviruses (SaVs) in acute diarrhea patients, as well as their relation to age, sex, and season.

BACKGROUND

Acute gastroenteritis is one of the most common diseases affecting children <5 years old and viral agents with approximately >75% are the major causative agent of acute infectious diarrhea. After Rotavirus and Norovirus, the greater viral agents of acute gastroenteritis include HAstVs, HAdVs, and SaVs. To the best of our knowledge, there are sparse studies in Iran detecting at least three enteric viruses as causative agents of diarrhea simultaneously.

METHODS

The sample was collected from children referring to pediatric medical centers in Tehran, Iran; they were tested for Astrovirus, enteric Adenovirus, and Sapovirus by conventional PCR method. The association of incidence of viral enteric agents was evaluated with age, sex and seasonal pattern in children <5 years old.

RESULTS

The positive case number among acute gastroenteritis patients was 17/120 (14.1%). Patients ranged in age within 1-60 months, but 52.9% were aged ≤ 12 months. Males comprised the majority (70.6), and the male: female ratio was 2.4. HAstV was the most frequently detected virus (6.7%), while SaVs were detected only in 2.5% of cases. Mixed infections were not detected in these samples. The highest rate of HAstV was identified in winter (66.7%), HAdV in fall (66.7%), and SaV in winter (33.3%).

CONCLUSION

These findings underscore the importance of monitoring the epidemiology of HAstV, HAdV, and SaV as causative agents of viral diarrhea infections.

First evidence of a new simian adenovirus clustering with Human mastadenovirus F viruses

Background

Adenoviruses play an important role as human pathogens, though most infections are believed to be asymptomatic. The over 100 human adenovirus types are classified into seven species (A-G), some of which include simian adenoviruses. Recent findings have highlighted that simian adenoviruses have a zoonotic potential and that some human adenoviruses are likely the result of relatively recent spillover events.

Methods

In order to evaluate the risks associated with primates hunted and sold as bushmeat, multiple samples from 24 freshly killed monkeys were collected in the Republic of the Congo and tested for adenovirus DNA by PCRs targeting the conserved DNA polymerase and hexon genes.

Results

The DNA of a novel simian adenovirus was detected in a moustached monkey (Cercopithecus cephus) by the DNA polymerase PCR, but not by the hexon PCR. The 275 nucleotide amplicon was most closely related to members of the Human mastadenovirusF species (93% HAdV-40 and 89% HAdV-41 amino acid identity), rather than to other known simian adenoviruses.

Conclusions

The phylogenetic clustering with Human mastadenovirusF sequences suggests a common ancestor, more recent than the last common ancestor of humans and moustached monkeys. The findings increase concerns about the zoonotic potential of simian adenoviruses and highlight the need for more research and surveillance on the issue.

Molecular analysis of human adenoviruses in hospitalized children <5 years old with acute gastroenteritis in Tehran, Iran

Human adenoviruses (HAdVs), especially AdV-40 and 41, are common causes of nonbacterial sporadic and outbreak gastroenteritis in children. The present study aimed to describe the frequency and genetic analysis of HAdVs in hospitalized children <5 years old with acute gastroenteritis. A total of 376 stool samples obtained from June 2015 to December 2017 were investigated for the presence of HAdVs by polymerase chain reaction. The HAdV DNA was detected in 16 (4.3%) out of 376 stool samples. Based on the hexon hypervariable region (HVR), B, C, and F HADV species including five types HAdV-1, 2, 3, 6, and 41 were identified, among which enteric AdV species F (EAdV-41) was the most dominant. Moreover, our findings showed the presence of genomic type cluster 1 (GTC1) pattern in Iranian type 41 strains, which was closely similar to the D1 prototype strain (Tak) and D28. In this regard, a recombination was found in AdV-41 strains presenting the hexon sequence that belonged to GTC1, while fiber sequence clustered with GTC2.

Systematic review of the rotavirus infection burden in the WHO-EMRO region

Rotavirus gastroenteritis imposes a heavy burden on low- and middle-income countries. The World Health Organization defines the Eastern Mediterranean region (WHO-EMRO) as a diverse area in terms of socioeconomic status and health indicators. Rotavirus vaccination has been introduced, at least partially, in 19 out of the 22 EM countries; however, vaccine coverage remains low, and data on rotavirus disease burden is scarce.Available data on rotavirus prevalence, seasonality, vaccination status, and genotype evolution was systematically compiled following a literature review that identified 165 relevant WHO-EMRO epidemiology studies published between 1990 and 2017.Although the infectious agents responsible for acute gastroenteritis vary over time, rotavirus remained the leading cause of acute gastroenteritis in children, as seen in 76.3% of reviewed publications. Younger children (<2 years old) were at higher risk and thus increased vaccination coverage and surveillance systems are required to reduce the rotavirus gastroenteritis burden in WHO-EMRO countries.

Quinolone and Macrolide-Resistant Campylobacter jejuni in Pediatric Gastroenteritis Patients from Central Iran

Aims: To determine the prevalence and the antibiotic resistance patterns of Campylobacter jejuni isolated from pediatric diarrhea patients in central Iran. Materials and Methods: Stool specimens (n = 230) were investigated using a modified Gram stain, two specific culture media, and C. jejuni-specific PCR. Antibiotic resistance profiles and relevant resistance genes were determined. Genetic relationships among a selection of the isolates were studied by Fla typing. Results: Out of the 230 diarrhea samples, 48 (20.8%) cases of C. jejuni were identified using modified Gram stain, 45 (19.5%) using the culture media, and 76 (33%) cases were identified using PCR. The highest antibiotic resistance rates were observed in 37 (82.2%) strains against tetracycline, in 32 (71.1%) against ciprofloxacin, and in 31 (68.8%) against erythromycin. Twenty (44.4%) isolates were resistant to ciprofloxacin and erythromycin simultaneously. Genotypic investigations found 36 (97.3%) strains carrying the tet (o) gene, 31 (96.8%) harboring the cmeB gene, 22 (68.7%) strains with the gyrA6 gene, 20 (64.5%) strains containing a 23S rRNA mutation, and 21 (65.6%) strains with the qnrS gene. Fla typing of a random subset of 14 strains revealed 11 different types showing the genomic diversity of the isolates. Strains sharing the same Fla type could be easily distinguished by their resistance gene profile. Conclusions: This is the first study to demonstrate that genetically diverse quinolone-macrolide-resistant C. jejuni is an important cause of gastroenteritis in children from central Iran. Pediatricians should consider these resistance features once the antibiotic prescription is necessary for prevention of possible complications, especially in those under 5 years of age. Of note, most cases of Campylobacter diarrhea are self-limiting and antibiotics should only be prescribed in those cases where severe complications evolve.

Molecular detection of human adenovirus in urban wastewater in Egypt and among children suffering from acute gastroenteritis

Incidence of enteric viruses in sewage, the efficacy of wastewater treatment plants to remove these viruses, and health effects from their release into the surface water are very important environmental issues in the microbiology field. One of the most pathogenic enteric viruses is adenovirus which can cause a serious disease such as gastroenteritis with low grade fever and mild dehydration in humans. In this study we performed qualitative polymerase chain reaction (PCR) analysis of HAdV on 60 stool samples from children with acute gastroenteritis admitted to Abu-Rish hospital and 96 environmental samples (32 raw sewage, 32 treated sewage, 32 sewage sludge) collected from Zenin wastewater treatment plant (WWTP). HAdV were detected in 17 (28.3%) of stool, 27 (84.4%) of raw sewage, 16 (50%) of treated sewage and 25 (78%) of sludge samples. The viral concentrations were in the range of 2.02 × 10⁶-7.23 × 10⁶, 8.7 × 10⁵-4.3 × 10⁶, 1.22 × 10⁴-3.7 × 10⁶ and 1.48 × 10⁶-1.77 × 10⁷ GC/mL in stool, raw sewage, treated sewage, and sludge, respectively. HAdV was detected throughout the whole year of sample collection. Moreover, our results suggested that males were more susceptible to adenovirus infections than females. The results indicate that the high incidence of HAdV in the treated sewage may cause adverse health effects.

Detection of enteric- and non-enteric adenoviruses in gastroenteritis patients, Bangladesh, 2012-2015

Human adenoviruses (HAdVs) are common cause of nonbacterial acute gastroenteritis worldwide. Limited data exist on HAdVs molecular epidemiology associated with acute gastroenteritis in Bangladesh. We describe the genetic diversity and epidemiology of HAdVs among hospitalized diarrhea patients, including HAdV genotypes, clinical symptoms, and co-infecting enteric pathogens. Stool samples were collected from ongoing diarrhea surveillance during 2012-2015. HAdV was detected using PCR and genotyped by sequencing and phylogenetic analysis. Detailed socio-demographic and clinical information regarding each individual was recorded such as duration of diarrhea, dehydration status, vomiting, abdominal pain, fever, and severity. Of 871 fecal specimens, HAdV DNA was detected in 93 (10.7%). Among them 56% were co-infected with other known enteric viral and bacterial pathogens and 31.6% had severe gastroenteritis. The majority (55%) of HAdV positives were children <5 years of age. Two main clinical symptoms in HAdV infected patients were diarrhea and vomiting. HAdVs were detected throughout the year with low prevalence in winter (November-January). Five HAdV species (A, B, C, D, and F) including 17 different genotypes were identified during the study period, with enteric HAdV species F (HAdV-40/41) being the most dominant. However, non-enteric HAdV were also detected in substantial proportion of specimens (15% species C, 15% species D, 10.8% species A, and 4.3% species B). Our study demonstrates high genetic diversity of HAdVs including enteric and non-enteric HAdVs among diarrhea patients and provides a foundation for further clarification of the role of non-enteric HAdVs in diarrheal diseases.

Update on the epidemiology of rotavirus in the Middle East and North Africa

Rotavirus (RV) is the leading cause of severe acute gastroenteritis (AGE) worldwide. Consequently, we conducted a systematic literature review on articles studying RV in the 25 countries of the MENA region during the past 15years (2000-2015). The methods and reporting were set according to the 2015 preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) and based on the elements from the international prospective register of systematic reviews (PROSPERO). Our literature search identified 169 studies meeting our predefined inclusion criteria. Studies reporting on RV were conducted in 19 out of the 24 countries of the MENA region. The largest number of studies was reported in Turkey (n=32), Iran (n=31), Saudi Arabia (n=19) and Egypt (n=17). The majority of studies reporting on RV gastroenteritis rates were clinical observational studies. In 115 studies out of 169, RV was reported among in-patients whereas 35 studies reported RV among outpatients. The predominantly reported RV genotype in the region was G1[P8] followed by G2[P4] and G9[P8]. The majority of studies (n=108) were conducted among children less than 5years of age whereas the remaining studies reported on AGE among other age groups and rarely adults. In MENA countries, RV infection was reported all year round with peaks described in cold as well as hot months. This systematic review provides a current update on the epidemiology of RV-associated gastroenteritis in countries of the MENA region and draws attention to the major gaps existing in the continuous monitoring of RV.

Epidemiology of Rotavirus in the Iranian Children: A Systematic Review and Meta-analysis

Rotavirus is associated with increased risk for severe diarrhea in infants and young children worldwide. This systematic review and meta-analysis was performed to determine the prevalence rate of rotavirus from different parts of Iran and provide an overall relative frequency (RF) for Iran. We performed a systematic literature review from several databases including PubMed, ISI Web of Science, Scopus, OVID, MAG IRAN, IranMedex, and Iranian Scientific Information Database. We searched the following keywords: "rotavirus," "rotavirus infection," "acute gastroenteritis," "diarrhea," "children," "infant," and "Iran." The purpose of this study was to report the prevalence of rotavirus with the application of meta-analysis. We selected 43 researches out of 1147 for our study. From all the samples, the pooled estimate of prevalence (95% confidence interval) =39.9% (0.396%-0.409%) were rotavirus positive. It should be noted that rotavirus infection's RF varied from 6.4% to 79.3% in Birjand and Tehran Provinces, respectively. Thereupon, it is divergent in different studies. According to our study result, rotavirus RF has a wide range in Iran and is associated with diarrhea in children. Thus, further researches should be taken to minimize the emergence and transmission of rotavirus.

Molecular Epidemiology of Enteric Adenovirus Gastroenteritis in under-Five-Year-Old Children in Iran

Background. Acute gastroenteritis is one of the major sources of morbidity and mortality among young children in developed and developing countries. The aim of this study was to determine the prevalence of human adenovirus- (HAdV-) 40 and HAdV-41 in children hospitalized with gastroenteritis in five different health centers of Iran. Methods. In a cross-sectional epidemiological study, we studied 2682 fecal specimens that were collected from children under the age of 5 years in five educational and therapeutic pediatric centers in Iran from February 2012 to February 2013. Samples were tested for HAdV-40 and HAdV-41, using a specific pair of primers in polymerase chain reaction (PCR) method. Results. HAdV-40 and HAdV-41 were detected in 132 (5.18%) of the patients with diarrhea. A significantly higher prevalence of HAdV-40 and HAdV-41 (58.3%) was observed in children under 12 months of age, compared to other age groups. The male to female ratio was 1.7. Conclusion. The results of this study demonstrated that HAdV-40 and HAdV-41 could be considered etiological agents for acute gastroenteritis among children in Iran. The PCR as a rapid test may increase the chance for a relatively mild course of the disease followed by a complete recovery and avoiding administration of unnecessary antibiotics.

Frequency of adenoviruses, rotaviruses and noroviruses among diarrhea samples collected from infants of zabol, southeastern iran

Background:

Viruses are one of the major reasons of gastrointestinal disease worldwide, and commonly infect children less than five years of age in developing countries.

Objectives:

The current study aimed to determine the frequency of adenoviruses, rotaviruses and noroviruses among diarrhea samples collected from infants of Zabol, south-east of Iran. This study is the first investigation of adenoviruses, rotaviruses and noroviruses among diarrhea samples in Zabol.

Patients and Methods:

In this study, eighty-two diarrhea stool samples were collected from infants aged < 1 to 12 months admitted to the hospital, internal laboratory and central laboratory of Zabol, Iran. All samples were subjected to the rapid immunochromatography assay.

Results:

The results showed that the frequency of rotaviruses, adenoviruses and noroviruses among infants with diarrhea were 70.20%, 20.30% and 9.50%, respectively. There were 50 subjects aged one to five months and 2 subjects aged nine to twelve months. The results of geographical distribution showed that the number of infants living in rural and urban areas with these viruses were 50 and 32, respectively. Rotaviruses were most common in rural and urban infants with 42 and 10 cases, respectively. Regarding the feeding patterns of infants with diarrhea, mixed feeding and breast feeding were found in 51 and 31 cases, respectively.

Conclusions:

In conclusion, the results of our study showed that the major viral pathogens that caused infantile diarrhea in Zabol city were rotaviruses followed by adenoviruses and noroviruses. The results of our study can useful for prosperous control of infantile diarrhea.

Rotavirus Infection in Children with Acute Gastroenteritis in Iran: A Systematic Review and Meta-analysis

BACKGROUND

The recent studies show that Rotavirus is important cause of the acute gastroenteritis. The aim of this review is to estimate the number of Rotavirus infection among Iranian children by performing a systematic review and estimating a pooled data.

METHODS

We performed a systematic literature review in relevant databases including PUBMED, MEDLINE, OVID, SID, MAGIRAN, and IRANMEDEX. Search in databases was done in October 10, 2013. Meta-analysis was performed using the STATA statistical package version 11. We assessed heterogeneity by Q-test and used random model for pooling measures of proportion of Rotavirus infection among Iranian children with diarrhea (and 95% confidence intervals [CI]). Sub group analysis between in-patient and outpatient group were done and publication bias was assessed by Egger and Begg tests.

RESULTS

A total of 154 records were identified in our searching. There were 36 studies including a total of 15,368 children with diarrhea. Out of 15,368 children, 6,338 were positive for Rotavirus gastroenteritis. Overall pooled estimate of infection with Rotavirus among cases of gastroenteritis was 0.35 (95% CI, 0.28-0.41). Pooled estimates for hospitalized children and outpatient subgroups were 0.39 (95% CI, 0.30-0.48), and 0.31 (95% CI, 0.23-0.38), respectively.

CONCLUSIONS

This study supports the importance of Rotavirus in the Iranian population such as common cause of diarrhea among children. Therefore, decision to adopt immunization programs to prevent Rotavirus infection might be helpful in Iran.