Acute viral gastroenteritis in children hospitalized in Iksan, Korea during December 2010-June 2011

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.

Use of multiplex PCR in diagnosis of childhood acute viral diarrhoea caused by rotavirus, norovirus, astrovirus and adenovirus in Upper Egypt

Background

Diarrhoea is still a major public health issue in developing countries, and it is one of the leading causes of morbidity and mortality in children. We aimed to assess the use of a multiplex reverse transcription polymerase chain reaction (RT-PCR) assay for the detection of five viruses, including rotavirus, norovirus (genogroups 1 and 2), astrovirus, and adenovirus, responsible for gastroenteritis in children under 5 years old in primary care centres in Upper Egypt.

Subjects and methods

A total of 500 stool samples were collected. Fifty samples were randomly selected for viral examination using multiplex RT-PCR for the detection of rotavirus, norovirus (genogroups 1 and 2), astrovirus, and adenovirus, causing diarrhoea.

Results

Viruses were detected in 45 (90%) of the 50 stool samples. The most frequently identified virus was norovirus G2, followed by Group A rotavirus, astrovirus and adenovirus. Mixed infection by two and three viruses was observed in 7/50 cases (14%) and 2/50 cases (4%), respectively. Norovirus G1 was not detected in the samples examined.

Conclusion

Our study reveals that multiplex PCR allows for the detection of multiple viral targets in only one reaction, rendering the assay easier to perform compared to existing testing methodologies (RT-PCR and electron microscopy). Additionally, most of the viruses were detected in summer, and the highest prevalence was in the age group less than 1 year. Norovirus G2 and rotavirus were the most frequent agents and the most common coinfections responsible for gastroenteritis in children.

Astrovirus infection in hospitalized children: Molecular, clinical and epidemiological features

BACKGROUND

Astrovirus (HAstV) is a common viral pathogen that causes gastroenteritis worldwide. It is classified into eight classical human types (HAstV-1/8) and seven other less prevalent types, described as HAstV VA1, VA2, VA3, VA4, MLB-1, MLB-2 and MLB-3. During outbreaks, the elderly and children are the most affected, and the spread of the virus is associated with person-to-person contact, food ingestion and contaminated water.

OBJECTIVES

The aim of the present study was to investigate the prevalence of infection and genetic diversity of HAstV strains. Samples were collected from children with acute gastroenteritis admitted to a large pediatric hospital during a surveillance period of three years (2008-2011) in Belém city, Pará State, Amazon Region, Northern Brazil.

STUDY DESIGN

Screening and genotyping tests were conducted using RT-PCR to detect the classical and non-classical HAstV types using specific primers. A semi-nested RT-PCR protocol was developed to improve viral detection in samples with a low viral load.

RESULTS

The overall positivity observed in this study was 3.9% (19/483). The age distribution showed a high prevalence of positive cases in children under one year old (5.3%). We found vomiting associated with 75% of the positive cases, fever with 82.3%, and dehydration with 76.9%. Most patients with positive cases demonstrated two to five days of diarrhea, two to three episodes of vomiting during hospitalization, and three bowel movements per day. Co-infection with HAstV and norovirus was observed in three cases (15.8%), and no pattern of seasonality or any relationship between the HAstV positivity rate and climate variables was observed. Eighteen positive samples (94.7%-18/19) were genotyped based on the ORF 2 region, and the greatest prevalence was of HAstV-1a (66.6%-12/18), followed by HAstV-2 (22.2%-4/18, comprising two type-2b and two type-2c genotypes), HAstV-3c (5.6%-1/18) and HAstV-4c (5.6%-1/18). No non-classical types were detected in the clinical samples analyzed.

CONCLUSIONS

The present study showed that although HAstV infections occur at low frequency, they are involved in severe pediatric cases of acute gastroenteritis presenting with a high diversity of strains, including the lineages 3c and 4c, which were never before detected in Brazil.

Recent viral pathogen in acute gastroenteritis: a retrospective study at a tertiary hospital for 1 year

PURPOSE

Viral gastroenteritis among children is mainly caused by rotavirus, norovirus, astrovirus, or adenovirus strains. However, changing socioeconomic conditions and a rotavirus vaccination program may be affecting the prevalence of these viral infections. Therefore, we aimed to elucidate the season-specific trends in viral infections for facilitating prophylaxis and surveillance in our region.

METHODS

We evaluated 345 pediatric patients (203 males, 142 females; age, 1 month to 16 years) who visited the CHA Bundang Medical Center because of gastroenteric symptoms between June 2014 and May 2015. The specimens were simultaneously tested for norovirus, rotavirus, astrovirus, and adenovirus via multiplex reverse transcription polymerase chain reaction. Clinical characteristics of patients were analyzed retrospectively.

RESULTS

The most common virus was norovirus, followed by rotavirus, adenovirus, and astrovirus. Of all viral infections, 45.2% occurred mainly between 6 and 24 months of age; in particular, norovirus infection mostly occurred in all age groups except those below 6 months of age, when rotavirus was most prevalent. In addition, seasonal variation was observed, such as norovirus infection from December to February, rotavirus infection from February to April, and adenovirus infection from July to October.

CONCLUSION

Our results showed that the most common cause of acute pediatric viral gastroenteritis had changed from rotavirus to norovirus in our patients, because of effective rotaviral vaccination. We recommend the management of food and personal hygiene in accordance with age or seasons as well as active vaccination for preventing viral gastroenteritis.

Tropical and travel-associated norovirus: current concepts

PURPOSE OF REVIEW

We highlight recent advances relevant to understanding norovirus infections in the tropics, both in populations living in developing settings and travelers to these regions.

RECENT FINDINGS

Because of the decrease in diarrheal disease associated with the global rollout of vaccines against rotavirus, norovirus is emerging as the predominant cause of diarrhea morbidity among children in the tropics, and evidence suggests that it contributes to adult disease in endemic populations and travelers. In addition to identifying potential target populations for preventive measures, we provide an update on norovirus vaccine development and concepts related to their implementation in low-income and middle-income countries.

SUMMARY

These current concepts related to norovirus-attributable disease burden, clinical significance, and economic impact can potentially be applied to tailoring efforts to prevent and mitigate the effects of this important enteropathogen.

Noroviruses: epidemiology, immunity and prospects for prevention

In recent years, noroviruses have become recognized as an important cause of both sporadic and epidemic acute gastroenteritis (AGE), largely due to the improved availability of broadly reactive real-time RT-PCR (TaqMan-based RT-PCR) assays. While there is substantial diversity among noroviruses, one specific genotype, GII.4, is the most common etiology in sporadic and epidemic AGE. Outbreaks of norovirus AGE most commonly occur in healthcare facilities and restaurants and result in significant morbidity and mortality and substantial healthcare costs. Norovirus vaccine development is progressing, and Phase I and II human trials have shown proof-of-principle that norovirus vaccines can reduce illness and infection.

Detection of rotavirus and other enteropathogens in children hospitalized with acute gastroenteritis in Havana, Cuba

The aim of the study was to diagnose infections with rotavirus and other enteric pathogens in children under five years old with acute gastroenteritis and to identify the most common epidemiological and clinical characteristics of these pathogens. The study was conducted using 110 stool samples from the same number of children under five years old who were inpatients at three paediatric hospitals in Havana, Cuba, between October and December 2011. The samples were tested for rotavirus and other enteric pathogens using traditional and molecular microbiological methods. Pathogens were detected in 85 (77.3 %) of the children. Rotavirus was the most commonly found, appearing in 54.5 % of the children, followed by bacteria (29 %) and parasites (10.9 %). Other viral pathogens detected included adenovirus (6.4 %) and astrovirus (3.6 %). In rotavirus-positives cases, at least one other pathogen was detected, usually a bacterium (26.6 %). More than three episodes of watery diarrhea in 24 hours were observed in 78.3 % of the cases. Dehydration was found in 30 (50 %) rotavirus-positive children, of whom seven (11.6 %) were transferred to an intensive care unit due to complications of metabolic acidosis. Rotavirus was most commonly observed among children under 12 months old (65 %). The highest incidence of infection occurred in children who were under the care of a relative at home (78.3 %), had not been breastfed (65 %), or had been breastfed for less than six months (28.3 %). The genotype combinations most frequently found were G9P8 (28.3 %) and G1P8 (10 %). This study demonstrates the presence of rotavirus and other enteric pathogens as causes of gastroenteritis in hospitalized infants and young children in Cuba.

Clinical characteristics and molecular epidemiology of noroviruses in outpatient children with acute gastroenteritis in Huzhou of China

BACKGROUND

Noroviruses (NoVs) are considered major causative pathogens associated with the morbidity and mortality of young children with acute gastroenteritis. However, few studies have examined NoVs causing acute diarrhea among outpatient children worldwide. This study was conducted to investigate the clinical features and molecular epidemiology of NoVs in outpatient children with acute gastroenteritis in Huzhou, China, between April 2013 and April 2014.

METHODS

Stool specimens from 1346 outpatient children enrolled (under 5 years of age) with acute gastroenteritis were examined for NoVs by multiplex RT-PCR, and sequences of the partial capsids of NoVs were analyzed phylogenetically, while the relevant clinical data were analyzed statistically.

RESULTS

Of 1346 specimens, 383 (28.5%, 383/1346) were positive for NoVs. The proportion of GII genotypes (26.9%) was significantly higher than that of GI genotypes (1.6%). The GII.4 genotype was the most prevalent of GII genotypes and was clustered into GII.4/Sydney (37.8%) and GII.4/2006b (62.2%), whereas GI strains were clustered into GI.1. Additionally, the younger children (12 to <24 months of age) were more susceptible to NoVs than children in other age groups, and the highest percentage of NoV infections occurred in April 2013. The diarrheal frequency (times/d) and WBC counts of the infected outpatient group with NoVs were significantly higher than were those of the uninfected outpatient group.

CONCLUSION

NoVs were confirmed to be the major viral agents responsible for acute gastroenteritis in outpatient children in Huzhou, China, and GII.4/Sydney and GII.4/2006b variants were identified as the predominant strains in this study.

Molecular epidemiology of norovirus in South Korea

Norovirus is a major cause of viral gastroenteritis and a common cause of foodborne and waterborne outbreaks. Norovirus outbreaks are responsible for economic losses, most notably to the public health and food industry field. Norovirus has characteristics such as low infectious dose, prolonged shedding period, strong stability, great diversity, and frequent genome mutations. Besides these characteristics, they are known for rapid and extensive spread in closed settings such as hospitals, hotels, and schools. Norovirus is well known as a major agent of food-poisoning in diverse settings in South Korea. For these reasons, nationwide surveillance for norovirus is active in both clinical and environmental settings in South Korea. Recent studies have reported the emergence of variants and novel recombinants of norovirus. In this review, we summarized studies on the molecular epidemiology and nationwide surveillance of norovirus in South Korea. This review will provide information for vaccine development and prediction of new emerging variants of norovirus in South Korea.

High Incidence of Staphylococcus aureus and Norovirus Gastroenteritis in Infancy: A Single-Center, 1-Year Experience

PURPOSE

The etiology of acute gastroenteritis (AGE) has changed since the introduction of the rotavirus vaccination. The aim of this study was to clarify which common pathogens, both bacterial and viral, are currently causing AGE in infants.

METHODS

Infants with acute diarrhea were enrolled. We tested for 10 bacterial pathogens and five viral pathogens in stool specimens collected from infants with AGE. The clinical symptoms such as vomiting, mucoid or bloody diarrhea, dehydration, irritability, and poor oral intake were recorded, and laboratory data such as white blood cell count and C-reactive protein were collected. The clinical and laboratory data for the cases with bacterial pathogens and the cases with viral pathogens were compared.

RESULTS

Of 41 total infants, 21 (51.2%) were positive for at least one pathogen. Seventeen cases (41.5%) were positive for bacterial pathogens and seven cases (17.1%) were positive for viral pathogens. Staphylococcus aureus (13 cases, 31.7%) and Clostridium perfringens (four cases, 9.8%) were common bacterial pathogens. Norovirus (five cases, 12.2%) was the most common viral pathogen. Fever and respiratory symptoms were common in the isolated viral infection group (p=0.023 and 0.044, respectively), whereas other clinical and laboratory data were indistinguishable between the groups.

CONCLUSION

In our study, S. aureus (41.5%) and norovirus (12.2%) were the most common bacterial and viral pathogens, respectively, among infants with AGE.

Treatment of norovirus infections: moving antivirals from the bench to the bedside

Noroviruses (NV) are the most common cause of acute gastrointestinal illness in the United States and worldwide. The development of specific antiviral countermeasures has lagged behind that of other viral pathogens, primarily because norovirus disease has been perceived as brief and self-limiting and robust assays suitable for drug discovery have been lacking. The increasing recognition that NV illness can be life-threatening, especially in immunocompromised patients who often require prolonged hospitalization and intensive supportive care, has stimulated new research to develop an effective antiviral therapy. Here, we propose a path forward for evaluating drug therapy in norovirus-infected immunocompromised individuals, a population at high risk for serious and prolonged illness. The clinical and laboratory features of norovirus illness in immunocompromised patients are reviewed, and potential markers of drug efficacy are defined. We discuss the potential design of clinical trials in these patients and how an antiviral therapy that proves effective in immunocompromised patients might also be used in the setting of acute outbreaks, especially in confined settings such as nursing homes, to block the spread of infection and reduce the severity of illness. We conclude by reviewing the current status of approved and experimental compounds that might be evaluated in a hospital setting.