Molecular study of astrovirus, adenovirus and norovirus in community acquired diarrhea in children: One Egyptian center study

Evaluation of the detection of diarrhoea-associated RNA viruses in immunocompromised children in Iran

Background

Gastroenteritis accounts for about 10% of the deaths among children, especially in immunocompromised children. Few studies on the prevalence of gastrointestinal infections caused by RNA viruses have been done in Iran. The aim of the study was to evaluate the detection of RNA viruses causing diarrhoea using a multiplex PCR.

Methods

Stool samples were collected from 130 paediatric patients with diarrhoea who had acute lymphocytic leukaemia, non-Hodgkin lymphoma, and retinoblastoma. After RNA extraction and synthesis of cDNA, multiplex PCR was done to evaluate the presence of rotavirus, norovirus, astrovirus, and enterovirus.

Results

There were 9 (6.9%), 7 (5.4%), 3 (2.3%), and 6 (4.6%) cases of rotavirus, norovirus, astrovirus, and enterovirus detected, respectively. One case of co-infection with astrovirus and norovirus was observed.

Conclusions

This is the first report from Iran which identified the presence of common RNA viruses causing diarrhoea in immunocompromised children. Increased awareness of these viruses will enable healthcare professionals to improve strategies and policies to control spread and infection caused by these viruses.

Enteropathogenic viruses associated with acute gastroenteritis among African children under 5 years of age: A systematic review and meta-analysis

Gastroenteritis viruses are the leading etiologic agents of diarrhea in children worldwide. We present data from thirty-three (33) eligible studies published between 2003 and 2023 from African countries bearing the brunt of the virus-associated diarrheal mortality. Random effects meta-analysis with proportion, subgroups, and meta-regression analyses were employed. Overall, rotavirus with estimated pooled prevalence of 31.0 % (95 % CI 24.0-39.0) predominated in all primary care visits and hospitalizations, followed by norovirus, adenovirus, sapovirus, astrovirus, and aichivirus with pooled prevalence estimated at 15.0 % (95 % CI 12.0-20.0), 10 % (95 % CI 6-15), 4.0 % (95 % CI 2.0-6.0), 4 % (95 % CI 3-6), and 2.3 % (95 % CI 1-3), respectively. Predominant rotavirus genotype was G1P[8] (39 %), followed by G3P[8] (11.7 %), G9P[8] (8.7 %), and G2P[4] (7.1 %); although, unusual genotypes were also observed, including G3P[6] (2.7 %), G8P[6] (1.7 %), G1P[6] (1.5 %), G10P[8] (0.9 %), G8P[4] (0.5 %), and G4P[8] (0.4 %). The genogroup II norovirus predominated over the genogroup I-associated infections (84.6 %, 613/725 vs 14.9 %, 108/725), with the GII.4 (79.3 %) being the most prevalent circulating genotype. In conclusion, this review showed that rotavirus remains the leading driver of viral diarrhea requiring health care visits and hospitalization among under-five years children in Africa. Thus, improved rotavirus vaccination in the region and surveillance to determine the residual burden of rotavirus and the evolving trend of other enteric viruses are needed for effective control and management of cases.

Human adenoviruses in children with gastroenteritis: a systematic review and meta-analysis

PURPOSE

Human adenoviruses (HAdVs) have always been suggested as one of the main causes of gastroenteritis in children. However, no comprehensive report on the global epidemiology of these viruses in pediatric gastroenteritis is available.

METHODS

A systematic search was conducted to obtain published papers from 2003 to 2023 in three main databases PubMed, Scopus, and Web of Science.

RESULTS

The estimated global pooled prevalence of HAdV infection in children with gastroenteritis was 10% (95% CI: 9-11%), with a growing trend after 2010. The highest prevalence was observed in Africa (20%, 95% CI: 14-26%). The prevalence was higher in inpatients (11%; 95% CI: 8-13%) and patients aged 5 years old and younger (9%; 95% CI: 7-10%). However, no significant difference was observed between male and female patients (P = 0.63). The most prevalent species was found to be the species F (57%; 95% CI: 41-72%). The most common HAdVs observed in children with gastroenteritis were types 40/41, 38, and 2. Analysis of case-control studies showed an association between HAdV and gastroenteritis in children (OR: 2.28, 95% CI; 1.51-3.44).

CONCLUSION

This study provided valuable insights into the importance of HAdVs in children with gastroenteritis, especially in hospitalized and younger children. The results can be used in future preventive measurements and the development of effective vaccines.

Worldwide prevalence and genotype distribution of human astrovirus in gastroenteritis patients: A systematic review and meta-analysis

AIM

Human astrovirus (HAstV) is an important causative agent of gastroenteritis in humans, which mainly infects young children and the elderly. The goal of this study was to conduct a meta-analytic review of the prevalence of HAstV amongst patients with gastroenteritis, and to shed light on the connection between HAstV infection and gastroenteritis.

METHODS

Systematic literature searches were conducted to identify all potentially relevant studies recorded up to April 8th, 2022. For study weighting, the inverse variance method was employed and the random-effects model was applied to evaluate data. For case-control studies, the pooled odds ratio (OR) and 95% confidence interval (CI) were calculated to establish the relationship between HAstV infection and gastroenteritis.

RESULTS

Among 302423 gastroenteritis patients from 69 different countries, the overall pooled prevalence of HAstV infection was 3.48% (95% CI: 3.11%-3.89%). Case-control approach was used in 39 investigations, and the overall prevalence of HAstV infection among the 11342 healthy controls was 2.01% (95% CI: 1.40%-2.89%). Gastroenteritis and HAstV infection were associated with a pooled OR of 2.16 (95% CI: 1.72-2.71; P < 0.0001; I² = 33.7%). The most commonly found HAstV genotypes in gastroenteritis patients were HAstV1 (62.18%), HAstV7 (33.33%), and HAstV-MLB1 (17.43%).

CONCLUSION

The frequency of HAstV infection was the highest in children under the age of five, and in developing countries. The prevalence rate of HAstV was not influenced by gender. Semi-nested and nested RT-PCR were highly sensitive assays for detecting HAstV infections.

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.

Human Mastadenovirus Infections in Children: A Review of the Current Status in the Arab World in the Middle East and North Africa

Human mastadenovirus (HAdV) is a non-enveloped icosahedral virus with double-stranded DNA genomes. The mortality rate of HAdV infections can reach 35.5%, while gastroenteritis HAdV infections, HAdV pneumonia, and disseminated disease tend to show a worse outcome, with rates ranging from 44.2% to 50%. In addition, HAdV can cause infections at any age but most commonly in the pediatric population, especially in young children and infants. Therefore, this review aims to assess the current status of HAdV infections among children in the Arab World, particularly in the Middle East and North Africa. Web of Science, Scopus, PubMed, EMBASE, and Google Scholar databases for publications in English were searched up to July 2022 for relevant articles. The literature search yielded a total of 21 studies, which were included in this review. Studies reporting HAdV infections in children were conducted in 17 out of the 22 countries. The average prevalence rate of HAdV infections in children was 12.7%, with average prevalence rates of 12.82% and 12.58% in the Middle East and North African countries, respectively. The highest prevalence rate (28.3%) was reported in Egypt, whereas the lowest prevalence (1.5%) was reported in Sudan. The included studies presented children with signs and symptoms of gastroenteritis, acute respiratory infection, acute diarrhea, and acute hemorrhagic conjunctivitis. In conclusion, the average prevalence rate of HAdV infections in children was 12.7%, with average prevalence rates of 12.82% and 12.58% in the Middle East and North African countries, respectively. Finding the precise prevalence rate of this virus is crucial because it will guide future planning for effective disease control and the selection of particular treatment options during epidemics and special seasons.

Viral pathogens of acute gastroenteritis in Egyptian children: role of the parechovirus

BACKGROUND AND AIM

Human parechovirus (HPeV) has emerged as a pathogen associated with acute gastroenteritis (AGE).

AIM

To detect the presence of HPeV in the stool samples from Egyptian children with AGE seeking care and the possibility of its co-infection with other enteric viruses.

METHODOLOGY

One hundred stool samples were collected from children attending Mansoura University Children's Hospital with AGE. HPeV and astrovirus were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). At the same time, detection of rotavirus antigen and norovirus was achieved by enzyme-linked immunosorbent assay and rapid immunochromatographic method, respectively.

RESULTS

The most frequently detected virus was rotavirus (39%), followed by norovirus (27%), HPeV (19%), and astrovirus (12%). Interestingly, the single infection with HPeV was 5%. Among the 19 HPeV positive samples, the co-infection of HPeV with other enteric viruses was detected in 9(43.9%) for rotavirus, 7(36.8%) for norovirus, 2(10.5%) for astrovirus, in 3(15.8%) for rotavirus and norovirus and 1(5.3%) for norovirus and astrovirus. Regarding the clinical presentation, there was no significant difference between children infected with HPeV alone and those infected with viruses other than HPeV alone; fever (p = 0.3), vomiting (p = 0.12), abdominal pain (p = 0.12), and grades of severity (P = 0.82). HPeV alone infected children were of mild severity (60%), and their main presenting symptom was fever (60%).

CONCLUSIONS

Detection of HPeV as a single viral pathogen in the stool of some children with AGE showed that this virus could be a causative agent of AGE in Egyptian children. Therefore, HPeV could be included as one of the viruses screened for AGE diagnosis in children in Egypt.

Quantitative RT-PCR detection of human noroviruses and hepatitis A virus in fresh produce and surface water used for irrigation in the Mansoura and Giza regions, Egypt

Surface water used as an irrigation source can be a significant source of viral contamination of fresh produce. Enteric viruses such as hepatitis A virus (HAV) and human norovirus genogroup I (HNoV GI) and genogroup II (HNoV GII) can be transmitted to human via fresh produce when irrigated with contaminated water or when prepared by infected food handlers. In the current study, we investigated the presence of HAV, HNoV GI and GII in fresh produce and surface water used in cultivation of this produce using real-time PCR. Samples were collected from six different points in the Mansoura and Giza regions, Egypt. Our analysis showed that at least one virus was found in 41.6% (30/72) of surface water samples and 27% (13/48) of fresh produce samples. HAV (23/72) with a mean viral concentration = 4 × 10⁶ genome copies/litre (GC/L) was the most frequently identified virus in surface water samples, followed by human norovirus genogroup II (HNoV GII) (15/72, with a mean concentration = 1.2 × 10⁶ GC/L, and human noroviruses genogroup I (HNoV GI) (12/72, with a mean concentration = 1.4 × 10⁴ GC/L). Additionally, HAV (10/48) with a mean concentration = 5.2 × 10⁵ genome copies/gram (GC/g) was also the most frequently detected virus in the fresh produce samples, followed by HNoV GII (8/48, with a mean concentration = 1.7 × 10⁴ GC/g); meanwhile, HNoV GI (6/48) was less detected virus with a mean concentration = 3 × 10³ GC/g. This work suggests a wide prevalence of human enteric viruses in surface waters and fresh produce, which is of concern when the fresh produce is eaten raw. Thus, additional monitoring for viral pathogens in irrigation water and food is needed to increase the awareness of this issue to rise the control measures to reduce illness from contaminated food.

Polymerase Chain Reaction Study of Human Bocavirus in Children with Acute Gastroenteritis

Aim:

The present study aimed to detect Human bocavirus (HBoV) in stool samples from young children below 5 years complaining of acute gastroenteritis (GE) in addition to detection of rotavirus, norovirus, and astrovirus.

Methods:

The study included 90 children below 5 years with acute GE with excluded bacterial pathogens. The determination of the presence of HBoV was performed by nested polymerase chain reaction (PCR) beside determination of astrovirus and norovirus by multiplex PCR and rotavirus antigen by enzyme-linked immunosorbent assay (ELISA).

Results:

The most prevalent virus among the studied viruses was rotavirus (33.3%) detected by ELISA for antigen in the stool. The other three viruses detected by molecular methods were bocavirus (14.4%), astrovirus (13.3%), and norovirus (10%). Mixed viral infection with two or more viruses was detected in 16 children (17.8%). The most common was bocavirus and rotavirus in 6 patients (37.5%). In the study of demographic and clinical presentations of the children with HBoV, the affected children were mainly females, i.e., 10 (76.9%), from rural residence i.e., 11 (84.6%) with the mild classification of GE in 7 children (53.8%) and moderate GE in 6 children (46.2%) and none of them had severe GE. Fever was the most common presenting sign in those children (53.8%) followed by vomiting (46.2%).

Conclusion:

The study highlights the existence of HBoV in children with acute GE under the age of five. The infection associated with this virus was either mild or moderate in severity. The combined viral infection was common especially associated with rotavirus. There is a need for further additional study to identify the type of the circulated strain of bocavirus and the confections with other pathogens.

Prevalence and seasonal pattern of enteric viruses among hospitalized children with acute gastroenteritis in Samawah, Iraq

Almost all of the deaths happening under the age of 5 occur in the developed countries of Africa and Asia. This study included children admitted to the surgical care, aged 6 months to 5 years, who suffered from acute gastroenteritis and received treatment at Samawah, Iraq, from December 2018 to December 2019. Test results detected different types of rotaviruses, adenoviruses, astroviruses using ELISA. 56.6% of the infections were attributed to a viral pathogen. The main cause was attributed to rotavirus and adenovirus. The causative agents of diarrheal diseases in 28.1% of cases are rotaviruses, in 17.05% – adenoviruses, in 11.43% – astroviruses. Viral mono-infections are detected more often than mixed infections. Viral intestinal infections are characterized by seasonality and rise in the cold season, with a peak incidence of rotavirus infection in April, adenovirus infection in November, and astrovirus infection in December.

High divergence of human astrovirus genotypes circulating in pediatric patients hospitalized with acute gastroenteritis in Chiang Mai, Thailand, 2017-2020

Human astrovirus (HAstV) is one of the common causes of acute gastroenteritis in children. The investigation of molecular epidemiology of HAstV is essential for monitoring the emergence and/or re-emergence of new HAstV genotypes, as well as understanding the evolution of HAstV circulating in children suffering from acute gastroenteritis. The present study aimed to investigate the prevalence and distribution of HAstVs strains circulating in children hospitalized with acute gastroenteritis in Chiang Mai, Thailand during 2017-2020. A total of 1500 fecal specimens collected from children with acute gastroenteritis were screened for HAstV by RT-PCR that targeted the partial RdRp in ORF1b and strains were characterized by sequencing and phylogenetic analysis. Of the 1500 fecal samples, 39 (2.6%) were positive for HAstV. Of these, both classic and novel HAstV genotypes, including classic HAstV1-HAstV5, novel HAstV-MLB1, MLB2, and HAstV-VA2, were detected. The data in this study revealed a high divergence of HAstV genotypes circulating in pediatric patients admitted to the hospitals with acute gastroenteritis in Chiang Mai, Thailand during 2017-2020.

Global prevalence and genotype distribution of norovirus infection in children with gastroenteritis: A meta-analysis on 6 years of research from 2015 to 2020

In the post rotavirus vaccine era, norovirus (NoV) plays an increasingly important role in epidemic and sporadic gastroenteritis among children. This study was designed to provide an updated meta-analytic review of the prevalence of NoV among paediatric patients with gastroenteritis and to clarify the relationship between NoV infection and gastroenteritis. Systematic searches of the literature for potentially relevant studies were carried out from 1 January 2015 to 29 May 2020. The inverse variance method was chosen for weighting of the studies, and the random-effects model was used to analyse data. To determine the association between NoV infection and gastroenteritis in children, pooled odds ratio (OR) and its 95% confidence interval (CI) were computed for case-control studies. The pooled prevalence of NoV infection among 12,0531 children with gastroenteritis from 45 countries across the world was 17.7% (95% CI: 16.3%-19.2%). There were 28 studies with a case-control design, and the pooled prevalence of NoV infection among 11,954 control subjects was 6.7% (95% CI: 5.1%-8.8%). The pooled OR of the association of NoV infection and gastroenteritis was 2.7 (95% CI: 2.2-3.4). The most common NoV genotypes were GII.4 (59.3%) and GII.3 (14.9%). The highest frequency of NoV was found in the age group below 1 year. Our findings indicated a substantial burden of gastroenteritis caused by NoV globally, with GII.4 and GII.3 the major genotypes responsible for the majority of NoV-associated gastroenteritis cases among children. Younger age and male sex can be considered risk factors for NoV-associated gastroenteritis among children.

Al-Kasaby N. Molecular Study of Norovirus in Pediatric Patients with Gastroenteritis

Aim:

The aim of the present study was to detect the prevalence of norovirus and genotypes determination by real-time PCR among children below 18 years as an etiology of acute gastroenteritis and to compare rapid detection of norovirus by Enzyme-Linked Immunoassay (ELISA) to virus detection by real-time PCR.

Methods:

The research was a cross-sectional study conducted on children below 18 years complaining of community-acquired acute gastroenteritis. A stool sample was subjected to direct-antigen detection by ELISA for norovirus and molecular study by real-time polymerase chain reaction.

Results:

The study included 200 children with acute gastroenteritis with a mean age of 6.7±3.8 years. Norovirus antigen was detected by EIA in 34.5% and by real-time PCR in 30.5% of studied children with genotype GII, the predominant detected genotype (80.97%). Both real-time PCR and antigen detection of norovirus were positive in 43 (70.5%) of the children and negative in 113(81.3%) of the studied children. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for antigen detection by ELISA were 70.5%, 81.3%, 62.3%, 86.3% and 78%, respectively. Comparison between patients positive for norovirus and those negative for norovirus by real-time PCR revealed non-significant difference as regards age, sex, the season of occurrence and residence.

Conclusion:

The present study highlights that norovirus prevalence is common among pediatric patients with gastroenteritis above 5 years with GII genotype as the prevalent genotype. There was a significant correlation between positive and negative results of antigen detection of norovirus by ELISA and detection of RNA of norovirus by real-time PCR in stool samples. However, the screening for norovirus by ELISA has limited sensitivity and needs to be associated with a molecular method for accurate diagnosis of sporadic cases of gastroenteritis.

Involvement of Egyptian Foods in Foodborne Viral Illnesses: The Burden on Public Health and Related Environmental Risk Factors: An Overview

Foodborne viral diseases are a major public health threat and pose a huge burden on the economies of both developed and developing countries. Enteric viruses are the causative agents of most foodborne illnesses and outbreaks. Egypt is classified by WHO among the regions with intermediate to high endemicity for various enteric viruses. This is manifested by the high prevalence rates of different enteric virus infections among Egyptian population such as Hepatitis A and E viruses, human rotaviruses, human noroviruses, human astroviruses, and human adenovirus. Recently, a number of foodborne gastroenteritis and acute hepatitis outbreaks have occurred in the US, Canada, Australia, and the European Union countries. Some of these outbreaks were attributed to the consumption of minimally processed foods imported from Egypt indicating the possibility that Egyptian foods may also be partially responsible for high prevalence of enteric virus infections among Egyptian population. In the absence of official foodborne-pathogen surveillance systems, evaluating the virological safety of Egyptian foods is a difficult task. In this review, we aim to provide a preliminary evaluation of the virological safety of Egyptian foods. A comprehensive review of prevalence studies on enteric virus infections shows hyperendemicity of several enteric viruses in Egypt and provides strong evidence of implication of Egyptian foods in these infections. We also address possible environmental risk factors that may lead to the contamination of Egyptian foods with enteric viruses. In addition, we describe potential obstacles to any plan that might be considered for improving the virological safety of Egyptian foods.

Quantitative PCR-based identification of enteric viruses contaminating fresh produce and surface water used for irrigation in Egypt

Fresh produce irrigated with surface water that may contain pathogens such as enteric viruses can lead to outbreaks of foodborne viral illnesses. In the current study, we performed real-time PCR (qPCR) to monitor the presence of enteric viruses such as human adenoviruses (HAdVs), hepatitis A virus (HAV), rotavirus group A (RVA), and norovirus GI (NoV GI) in surface water and fresh produce that were grown using this surface water in Egypt. Samples were collected on four occasions from different sites located in the Delta and in Greater Cairo, Egypt. Of the 32 water samples and 128 fresh produce samples, 27/32 (84.3%) and 99/128 (77.3%), respectively, were positive for at least one virus. HAdV (30/32) with a mean viral load = 1.5 × 10⁷ genome copies/L (GC/L) was the most commonly detected virus in water, followed by RVA (16/32, with a mean viral load = 2.7 × 10⁵ GC/L), HAV (11/32, with a mean viral load = 1.2 × 10⁴ GC /L), and NoV GI (10/32, with a mean viral load = 3.5 × 10³ GC/L). Additionally, HAdV (71/128, with a mean viral load = 9.8 × 10⁵ GC/g) was also the most commonly detected virus in the fresh produce, followed by NoV GI (43/128, with a mean viral load = 4.5 × 10³ GC/g), HAV (33/128, with a mean viral load = 6.4 × 10³ GC/g), and RVA (25/128, with a mean viral load = 1.5 × 10⁴ GC/g). Our results indicate that fresh produce may be contaminated with a wide range of enteric viruses, and these viruses may originate from virus-contaminated irrigation water. Moreover, this fresh produce may serve as a potential vector for the transmission of viral foodborne illnesses. These findings are important for future risk assessment analysis related to water/foodborne viruses. Graphical abstract . Please provide caption for Graphical AbstractGraphical abstract showing sample collection and processing.

Molecular Detection and Epidemiological Features of Selected Bacterial, Viral, and Parasitic Enteropathogens in Stool Specimens from Children with Acute Diarrhea in Thi-Qar Governorate, Iraq

Knowledge of etiology causes of diarrheal illness is essential for development and implementation of public health measures to prevent and control this disease syndrome. There are few published studies examining diarrhea in children aged <5 years in Iraq. This study aims to investigate the occurrences and epidemiology of selected bacterial (Salmonella spp. and Campylobacter spp.), viral (adenovirus, norovirus GI and GII, and astrovirus), and parasitic (Entamoeba spp. and Giardia spp.) agents in stool samples from 155 child diarrheal cases enrolled between March and August 2017, in a hospital-based cross-sectional study in Thi-Qar, southeastern Iraq. Using molecular techniques and sequence-based characterization, adenovirus was the most frequently detected enteropathogen (53/155 (34.2%)), followed by Salmonella spp. (23/155 (14.8%)), Entamoeba spp. (21/155 (13.5%)), and Campylobacter spp. (17/155 (10.9%)). Mixed infection with Salmonella spp. and Campylobacter spp. was evident, and the same was revealed between various enteric viruses, particularly adenovirus and norovirus. The most frequent co-infection pattern was between adenovirus and Campylobacter spp., in seven cases (7/155 (4.5%)). Whole-genome sequencing-derived typing data for Salmonella isolates (n = 23) revealed that sequence type 49 was the most prevalent in this sample set (15/23 (65.2%)). To the best of our knowledge, this study provides the first report on detection and identification of floR, bla_CARB-2, and mphA antimicrobial resistance genes in Salmonella isolated from children in the Middle East region. Logistic regression analysis pointed to few enteropathogen-specific correlations between child age, household water source, and breastfeeding patterns in relation to the outcome of detection of individual enteropathogens. This study presents the first published molecular investigation of multiple enteropathogens among children <5 years of age in Iraq. Our data provide supporting evidence for planning of childhood diarrhea management programs. It is important to build on this study and develop future longitudinal case-control research in order to elaborate the epidemiology of enteropathogens in childhood diarrhea in Iraq.

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.