Detection of astrovirus in premature infants with necrotizing enterocolitis

The emerging role of the gut virome in necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency in neonates, particularly preterm infants. Many factors can lead to NEC, but microbial dysbiosis is one of the most important risk factors that can induce this disease. Given the major role of the gut virome in shaping bacterial homeostasis, virome research is a fledgling but rapidly evolving area in the field of microbiome that is increasingly connected to human diseases, including NEC. This review provides an overview of the development of the gut virome in newborns, discusses its emerging role in NEC, and explores promising therapeutic applications, including phage therapy and fecal virome transplantation.

Exploration of pathogenic microorganism within the small intestine of necrotizing enterocolitis

BACKGROUND

Necrotizing enterocolitis (NEC) is the most common severe gastrointestinal emergency in neonates. We designed this study to identify the pathogenic microorganisms of NEC in the microbiota of the small intestine of neonates.

METHODS

Using the 16S ribosomal DNA (rDNA) sequencing method, we compared and analyzed the structure and diversity of microbiotas in the intestinal feces of different groups of neonates: patients undergoing jejunostomy to treat NEC (NP group), neonates undergoing jejunostomy to treat other conditions (NN group), and neonates with NEC undergoing conservative treatment (NC group). We took intestinal feces and saliva samples from patients at different time points.

RESULTS

The beta diversities of the NP, NN, and NC groups were all similar. When comparing the beta diversities between different time points in the NP group, we found similar beta diversities at time points E1 to E3 but significant differences between the E2-E3 and E4 time points: the abundances of Klebsiella and Enterococcus (Proteobacteria) were higher at the E1-E3 time points; the abundance of Escherichia-Shigella (Proteobacteria) increased at the E2 time point, and the abundance of Klebsiella decreased significantly, whereas that of Streptococcus increased significantly at the E4 time point.

CONCLUSIONS

Our results suggest that the pathological changes of intestinal necrosis in the small intestine of infants with NEC are not directly caused by excessive proliferation of pathogenic bacteria in the small intestine. The sources of microbiota in the small intestine of neonates, especially in premature infants, may be affected by multiple factors.

The Nonbacterial Microbiome: Fungal and Viral Contributions to the Preterm Infant Gut in Health and Disease

The intestinal microbiome is frequently implicated in necrotizing enterocolitis (NEC) pathogenesis. While no particular organism has been associated with NEC development, a general reduction in bacterial diversity and increase in pathobiont abundance has been noted preceding disease onset. However, nearly all evaluations of the preterm infant microbiome focus exclusively on the bacterial constituents, completely ignoring any fungi, protozoa, archaea, and viruses present. The abundance, diversity, and function of these nonbacterial microbes within the preterm intestinal ecosystem are largely unknown. Here, we review findings on the role of fungi and viruses, including bacteriophages, in preterm intestinal development and neonatal intestinal inflammation, with potential roles in NEC pathogenesis yet to be determined. In addition, we highlight the importance of host and environmental influences, interkingdom interactions, and the role of human milk in shaping fungal and viral abundance, diversity, and function within the preterm intestinal ecosystem.

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.

The value of autopsy in preterm infants at a Swedish tertiary neonatal intensive care unit 2002-2018

Reliable data on causes of death (COD) in preterm infants are needed to assess perinatal care and current clinical guidelines. In this retrospective observational analysis of all deceased preterm infants born < 37 weeks’ gestational age (n = 278) at a Swedish tertiary neonatal intensive care unit, we compared preliminary COD from Medical Death Certificates with autopsy defined COD (2002–2018), and assessed changes in COD between two periods (period 1:2002–2009 vs. period 2:2011–2018; 2010 excluded due to centralized care and seasonal variation in COD). Autopsy was performed in 73% of all cases and was more than twice as high compared to national infant autopsy rates (33%). Autopsy revised or confirmed a suspected preliminary COD in 34.9% of the cases (23.6% and 11.3%, respectively). Necrotizing enterocolitis (NEC) as COD increased between Period 1 and 2 (5% vs. 26%). The autopsy rate did not change between the two study periods (75% vs. 71%). We conclude that autopsy determined the final COD in a third of cases, while the incidence of NEC as COD increased markedly during the study period. Since there is a high risk to determine COD incorrectly based on clinical findings in preterm infants, autopsy remains a valuable method to obtain reliable COD.

Temporal and seasonal variations in incidence of stage II and III NEC-a 28-year epidemiologic study from tertiary NICUs in Connecticut, USA

OBJECTIVE

To investigate seasonality and temporal trends in the incidence of NEC.

STUDY DESIGN

A retrospective cohort study from two tertiary NICUs in northern and central Connecticut involving 16,761 infants admitted over a 28-year period. Various perinatal and neonatal risk factors were evaluated by univariate, multivariate, and spectral density analyses.

RESULTS

Incidence of NEC was unchanged over the 28 years of study. Gestational age, birth weight, and birth-months (birth in April/May) were independently associated with stage II or III NEC even after adjusting for confounding factors (p < 0.05). Yearly NEC incidence showed a multi-modal distribution with spectral density spikes approximately every 10 years.

CONCLUSION(S)

Temporal and seasonal factors may play a role in NEC with a peak incidence in infants born in April/May and periodicity spikes approximately every 10 years. These trends suggest non-random and possibly environmental factors influencing NEC.

The association between enteric viruses and necrotizing enterocolitis

Studies on necrotizing enterocolitis (NEC) have not largely focused on enteric viruses. In order to demonstrate the association between enteric viruses and NEC, stool specimens of 51 neonates with NEC and 39 "normal" neonates were collected to detect rotavirus (RV), astrovirus (ASV), sapovirus, enterovirus (EV), adenovirus (ADV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human bocavirus (HBoV). Rotavirus A (RVA), ASV, EBV, and ADV were detected in both the NEC and control groups; however, EV and HBoV were detected only in the NEC group and CMV was not detected in either group. ASV was the most common enteric virus, but no significant differences were found between NEC and control groups, as was similarly the case for EBV and EV. The prevalence of ADV and HBoV was higher in the NEC group than in the control group (P = 0.011, P = 0.005, respectively) but RVA showed the opposite trend (P = 0.014). Virus positivity or negativity had no influence on the clinical manifestation of NEC.Conclusion: The roles of different viruses in NEC are not congruent. Some, such as ASV, may be regarded as commensal in neonates, while in NEC patients, the presence of ADV and EBV may be related to severity of disease. What is known: • The etiology of NEC remains unknown. Studies on necrotizing enterocolitis (NEC) have not largely focused on enteric viruses and the conclusions were inconsistent. What is new: • Enteric viruses are common in the gut of neonates, but not all of them are pathogenic. • The existence of ADV and EBV may be related to the severity of NEC.

The viral dsRNA analogue poly (I:C) induces necrotizing enterocolitis in neonatal mice

BACKGROUND

Necrotizing enterocolitis (NEC) is a life-threatening gastrointestinal disease in premature infants with high mortality and morbidity with uncertain pathogenesis. Recent research focused on the role of intraluminal bacteria and lipopolysaccharide (LPS). However, an additional role of viral agents in the pathogenesis of NEC has recently been postulated. We assessed the role of polyinosinic:polycytidylic acid (pIC) mimicking viral dsRNA in contributing to the development of NEC in neonatal mice.

METHODS

Four-d-old C57BL/6J pups were stressed by asphyxia and hypothermia twice daily. Animals were either fed by formula only (FO), formula containing LPS or pIC. After 72 h, mice were euthanized, intestines harvested, and the severity of NEC was assessed.

RESULTS

Breastfed mice showed no evidence of NEC. Very mild NEC-like lesions were observed in mice fed by FO. Supplementation of LPS or pIC to the formula led to increased intestinal tissue damage and inflammation compared with FO in a similar manner.

CONCLUSION

Our study demonstrates the ability of viral factors to induce NEC in neonatal mice even in the absence of LPS. Furthermore, we present a new mouse model of pIC-induced NEC which may be used to obtain further mechanistic insights in the pathogenesis of this disease.

Gut microbiota and the pathogenesis of necrotizing enterocolitis in preterm neonates

Necrotizing enterocolitis (NEC) remains a devastating intestinal disease in preterm neonates. In this population, disruption of the gut microbiota development, mainly due to organ immaturity, antibiotic use and hospital microbial environment, plays a key role in the pathogenesis of NEC. This gut dysbiosis has been associated with opportunistic pathogens overgrowth, expression of virulence factors, altered metabolic functions and inflammatory dysregulated responses. In this review, we provide an updated summary of the host and gut microbiota interactions during the formative early life. We also explore the key determinants of gut dysbiosis in preterm neonates with NEC. Finally, we discuss the promising role of bacteriotherapy in the management of NEC, the aim being to shape or restore the beneficial gut bacterial communities.

Infectious causes of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency among premature infants. Although a large body of research has focused on understanding its pathogenesis, the exact mechanism has not been elucidated. Of particular interest is the potential causative role of infectious culprits in the development of NEC. A variety of reports describe bacterial, viral, and fungal infections occurring in association with NEC; however, no single organism has emerged as being definitively involved in NEC pathogenesis. In this review, the authors summarize the literature on infectious causes of NEC.

The neonatal bowel microbiome in health and infection

PURPOSE OF REVIEW

In newborns, interactions between the host and the microbiome operate synergistically, modulating host immune function and shaping the microbiome. Next generation molecular sequencing methodologies in tandem with modeling complex communities allow insights into the role of the microbiome in health and disease states. Infection-related disease states in which dysbiosis is integral include late-onset sepsis (LOS) and necrotizing enterocolitis (NEC), which still cause deaths and morbidity. Understanding microbiomic interactions may lead to alternative prevention, monitoring or treatment strategies, and modulation of long-term health outcomes especially in the preterm population. Recent studies have advanced understanding of the microbiome in NEC and LOS.

RECENT FINDINGS

Mechanisms of host-microbiome interaction have been demonstrated. Patterns of microbiomic change in association with NEC and LOS have been observed, with community changes dominated by Proteobacteria and Firmicutes appearing to precede NEC, and very early microbiomic signatures influencing LOS. Data on viral and fungal elements are emerging.

SUMMARY

Greater understanding of the neonatal bowel microbiome may allow tailored clinical practice and therapeutic intervention. Data handling and interpretation is challenging. Mechanistic studies of clinical interventions that affect the gut microbiome are important next steps.

Update in pathogenesis and prospective in treatment of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is among the most common and devastating diseases in neonates and, despite the significant advances in neonatal clinical and basic science investigations, its etiology is largely understood, specific treatment strategies are lacking, and morbidity and mortality remain high. Improvements in the understanding of pathogenesis of NEC may have therapeutic consequences. Pharmacologic inhibition of toll-like receptor signaling, the use of novel nutritional strategies, and microflora modulation may represent novel promising approaches to the prevention and treatment of NEC. This review, starting from the recent acquisitions in the pathogenic mechanisms of NEC, focuses on current and possible therapeutic perspectives.

The role of the intestinal microbiota in the pathogenesis of necrotizing enterocolitis

Development of necrotizing enterocolitis (NEC) requires a susceptible host, typically a premature infant or an infant with congenital heart disease, enteral feedings and bacterial colonization. Although there is little doubt that microbes are critically involved in the pathogenesis of NEC, the identity of specific causative pathogens remains elusive. Unlike established normal adult gut microbiota, which is quite complex, uniform, and stable, early postnatal bacterial populations are simple, diverse, and fluid. These properties complicate studies aimed at elucidating characteristics of the gut microbiome that may play a role in the pathogenesis of NEC. A broad variety of bacterial, viral, and fungal species have been implicated in both clinical and experimental NEC. Frequently, however, the same species have also been found in physiologically matched healthy individuals. Clustered outbreaks of NEC, in which the same strain of a suspected pathogen is detected in several patients suggest, but do not prove, a causative relationship between the specific pathogen and the disease. Studies in Cronobacter sakazakii, the best characterized NEC pathogen, have demonstrated that virulence is not a property of a bacterial species as a whole, but rather a characteristic of certain strains, which may explain why the same species can be pathogenic or non-pathogenic. The fact that a given microbe may be innocuous in a full-term, yet pathogenic in a pre-term infant has led to the idea of opportunistic pathogens in NEC. Progress in understanding the infectious nature of NEC may require identifying specific pathogenic strains and unambiguously establishing their virulence in animal models.

A clinical perspective of necrotizing enterocolitis: past, present, and future

Necrotizing enterocolitis (NEC) primarily affects premature infants. It is less common in term and late preterm infants. The age of onset is inversely related to the postmenstrual age at birth. In term infants, NEC is commonly associated with congenital heart diseases. NEC has also been associated with other anomalies. More than 85% of all NEC cases occur in very low birth weight infants or in very premature infants. Despite incremental advances in our understanding of the clinical presentation and pathophysiology of NEC, universal prevention of this disease continues to elude us even in the twenty-first century.

Coinfection in acute gastroenteritis predicts a more severe clinical course in children

The objectives of this study were to determine the incidence of enteric pathogens causing acute gastroenteritis (AGE) among hospitalized children in a large Italian hospital, to measure the incidence of coinfections, and to compare the clinical characteristics of those infected with one versus multiple agents. A prospective study was conducted from March 2010 to April 2011 at the Bambino Gesù Pediatric Hospital in Rome, Italy. All patients between 1 month and 16 years of age admitted to the Pediatric Department with a diagnosis of AGE were eligible for enrollment. Two stool samples for each patient were tested for gastrointestinal pathogens. We summarized the clinical severity of episodes, describing the duration of diarrhea, duration and frequency of vomiting, fever, and severity of dehydration. All the patients underwent medical evaluation with estimation of dehydration. One or more etiological agents were detected in 151 out of 232 patients (65.1%), while we did not detect any etiological agent in 81 (34.9%). Rotavirus was detected in 96 (63.6%), adenovirus in 17 (11.2%), norovirus in 7 (4.6%), toxin-producing Clostridium difficile in 23 (15.2%), Salmonella spp. in 15 (9.9%, B group in 12/15 and D group in 3/15), C. perfringens in 12 (7.9%), Campylobacter spp. in 6 (4%), and verotoxigenic Escherichia coli (VTEC) in 2 (1.3%). In 27 children out of 151 (17.9%), we found evidence of coinfection. Coinfection with rotavirus and toxin-producing C. difficile was the most common (63%). Children with coinfection had a more severe clinical presentation and had a higher probability to be severely dehydrated, independently of age and living community type.

Astrovirus and digestive disorders in neonatal units

AIM

To describe clinical signs associated with Human Astrovirus (HAstV) in stools in neonatal units.

METHODS

During 2005-2006, all stool virology performed for isolated digestive symptoms or suspicion of neonatal infection was tested for HAstV by an amplified enzyme-linked immunoassay (IDEIA™ Astrovirus test, Dako Cytomation). Each newborn with a positive result (HAstV+ group) was retrospectively matched with the first following symptomatic newborn in the same care unit having a negative stool virology (HAstV- group). Clinical data were collected during two 3-day periods (just after faecal samples collection and 1 week before) and compared within and between each group.

RESULTS

Human astrovirus was detected in faeces of 68 newborns [gestational age: 31.4(28.8-34) weeks] at a post-natal age of 23 (15-42) days without seasonal dominance. Human astrovirus+ and HAstV- groups were comparable. Bloody stool (54.4% versus 14.7%, p < 0.01) and stage II-III necrotizing enterocolitis (20.6% versus 4.4%, p < 0.05) were more frequently observed in HAstV+ than in HAstV- group; these associations were confirmed by logistic regression analysis.

CONCLUSION

This descriptive study argues for a possible association between HAstV and digestive symptoms in newborns specifically in preterm infants.

Absence of gastrointestinal pathogens in ileum tissue resected for necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is one of the most common gastrointestinal emergencies in premature infants and has been linked with viral antigens in as much as 40% of cases in single-center cohorts. We examined 28 tissue sections from surgically resected ileum from 27 preterm infants with NEC from 2 separate institutions for 15 common bacterial, viral, and parasitic gastrointestinal pathogens using multiplex reverse transcriptase polymerase chain reaction amplification and suspension array detection methods. We did not detect infectious enteritis pathogens in any of the NEC tissues and conclude that gastrointestinal pathogens are a rare cause of NEC.

A decrease in the number of cases of necrotizing enterocolitis associated with the enhancement of infection prevention and control measures during a Staphylococcus aureus outbreak in a neonatal intensive care unit

OBJECTIVE

Most cases of necrotizing enterocolitis (NEC) are sporadic, but outbreaks in hospital settings suggest an infectious cause. Our neonatal intensive care unit (NICU) experienced an outbreak of methicillin-sensitive Staphylococcus aureus (MSSA). We aimed to assess whether the enhancement of infection prevention and control measures would be associated with a reduction in the number of cases of NEC.

DESIGN

Retrospective chart review.

SETTING

A 24-bed, university-affiliated, inborn level 3 NICU.

PARTICIPANTS

Infants of less than 30 weeks gestation or birth weight ≤ 1,500 g admitted to the NICU between January 2007 and December 2008 were considered at risk of NEC. All cases of NEC were reviewed.

INTERVENTIONS

Infection prevention and control measures, including hand hygiene education, were enhanced during the outbreak. Avoidance of overcapacity in the NICU was reinforced, environmental services (ES) measures were enhanced, and ES hours were increased.

RESULTS

Two hundred eighty-two at-risk infants were admitted during the study. Their gestational age and birth weight (mean ± SD) were 28.2 ± 2.7 weeks and 1,031 ± 290 g, respectively. The proportion of NEC was 18/110 (16.4%) before the outbreak, 1/54 (1.8%) during the outbreak, and 4/118 (3.4%) after the outbreak. After adjustment for gestational age, birth weight, gender, and singleton versus multiple births, the proportion was lower in the postoutbreak period than in the preoutbreak period (P < .002).

CONCLUSION

Although this observational study cannot establish a causal relationship, there was a significant decrease in the incidence of NEC following implementation of enhanced infection prevention and control measures to manage an MSSA outbreak.

Astrovirus infection in hospitalized infants with severe combined immunodeficiency after allogeneic hematopoietic stem cell transplantation

Infants with severe primary combined immunodeficiency (SCID) and children post-allogeneic hematopoietic stem cell transplantation (HSCT) are extremely susceptible to unusual infections. The lack of generic tools to detect disease-causing viruses among more than 200 potential human viral pathogens represents a major challenge to clinicians and virologists. We investigated retrospectively the causes of a fatal disseminated viral infection with meningoencephalitis in an infant with gamma C-SCID and of chronic gastroenteritis in 2 other infants admitted for HSCT during the same time period. Analysis was undertaken by combining cell culture, electron microscopy and sequence-independent single primer amplification (SISPA) techniques. Caco-2 cells inoculated with fecal samples developed a cytopathic effect and non-enveloped viral particles in infected cells were detected by electron microscopy. SISPA led to the identification of astrovirus as the pathogen. Both sequencing of the capsid gene and the pattern of infection suggested nosocomial transmission from a chronically excreting index case to 2 other patients leading to fatal infection in 1 and to transient disease in the others. Virus-specific, real-time reverse transcription polymerase chain reaction was then performed on different stored samples to assess the extent of infection. Infection was associated with viremia in 2 cases and contributed to death in 1. At autopsy, viral RNA was detected in the brain and different other organs, while immunochemistry confirmed infection of gastrointestinal tissues. This report illustrates the usefulness of the combined use of classical virology procedures and modern molecular tools for the diagnosis of unexpected infections. It illustrates that astrovirus has the potential to cause severe disseminated lethal infection in highly immunocompromised pediatric patients.

An outbreak of necrotizing enterocolitis associated with norovirus genotype GII.3

BACKGROUND

Necrotizing enterocolitis (NEC) is an acute abdominal emergency of unknown etiology predominantly affecting preterm infants. We describe a cluster of NEC in a level III NICU involving 15 infants over a6-month period. Cohorting and stringent infection control measures were associated with termination of the cluster. A case-control study was used to investigate potential risk factors associated with development of NEC.

METHODS

Stool samples were collected from 55 infants (10 of 15 NEC and 45 non-NEC controls). Enteric pathogens were identified by culture and/or molecular diagnostic techniques. For the case-control study, controls were selected from admitted neonates during the same time and in the preceding 6-month period, matched for gestation and birthweight.

RESULTS

Forty percent (4/10) of NEC infants had norovirus RNA detected compared with 9% (4/45) of non-NEC infants (OR: 6.83, 95% CI: 1.3-34.9,P = 0.021). A lower rate of prolonged rupture of membranes and a higher rate of maternal smoking was also observed in NEC infants than in controls. No significant differences in incidences of chorioamnionitis, intrapartum antibiotics,volume of feedings, time of first formula feeding, and rates of patent ductus arteriosus or intrauterine growth retardation were detected.

CONCLUSIONS

Infants who developed NEC had an increased incidence of norovirus detection in their stool following diagnosis. This further strengthens the case for an etiologic role of norovirus in the pathogenesis of NEC.

Clinical characteristics of viral intestinal infection in preterm and term neonates

The clinical presentation of the viral enteric pathogens in newborn infants has not been adequately examined. The aim of this study was to evaluate the clinical characteristics of viral intestinal infections in newborn infants. Clinical data of all term and preterm infants admitted to our tertiary neonatal intensive care unit from 1998 to 2007 with clinical signs of gastroenteritis (GE) or necrotizing enterocolitis (NEC) were retrospectively reviewed and compared between infants with different viral enteric pathogens in stool specimens. In 34 infants with signs of GE or NEC, enteropathogenic viruses were found in stool specimens. Rotavirus was detected in 12 cases, of which two infants had NEC. Compared with infants with rotavirus or norovirus, infants with astrovirus more frequently suffered from NEC (p<0.05). In addition, an acute systemic inflammatory response was significantly more common in patients with astrovirus infection (astrovirus vs. rotavirus and astrovirus vs. norovirus, p < 0.01 and p < 0.05, respectively). Of eight children infected with norovirus, one infant had a systemic acute inflammatory response and NEC. This study demonstrates that in newborn infants, intestinal rotavirus, norovirus, and astrovirus infections may be associated with severe illness such as hemorrhagic enteritis resulting in bloody diarrhea or even NEC.

Prevalence of rotavirus, adenovirus, norovirus, and astrovirus infections and coinfections among hospitalized children in northern France

From January to December 2007, 973 stool specimens were prospectively collected from children hospitalized for gastroenteritis signs or from neonates and premature cases who were born in two French hospital settings in the north of France. They were tested by rapid enzyme immunoassay (EIA) analyses for rotavirus and adenovirus and by two commercially available ELISA tests for the detection of norovirus and astrovirus. The overall rates of prevalence for rotavirus, norovirus, adenovirus, and astrovirus were 21, 13, 5, and 1.8%, respectively, and they did not significantly differ between the two hospital settings (P=0.12). Mixed virus infections were detected in 32 (3.3%) of the 973 study children and were associated with norovirus in 21 (66%) infants, including 5 premature cases. From fall to spring, norovirus infections accounted for 52% of documented gastroenteritidis viral infections at a time when rotavirus was epidemic, resulting in mixed norovirus and rotavirus gastrointestinal tract infections. Of the 367 documented viral gastroenteritis cases, 15 (4.1%) were identified as nosocomial infections, 5 of which occurred in premature cases. These findings highlight the need to implement norovirus and astrovirus ELISA detection assays in association with rapid EIA rotavirus and adenovirus detection assays for the clinical diagnosis and the nosocomial prevention of gastroenteritis viral infections in pediatric departments.

Viral infections: new and emerging

PURPOSE OF REVIEW

Viral gastrointestinal diseases are a leading cause of childhood death worldwide. Recognition of specific causes as they pertain to epidemiology, pathogenesis, treatment, and prevention is necessary for the clinician as scientific advances allow for greater understanding of the diseases. The present review summarizes these advances for commonly encountered causes of viral gastroenteritis.

RECENT FINDINGS

Implementation of rotavirus vaccine has decreased the burden of this disease in many communities, and advances in molecular testing of the virus increase the ability to test for the virus. The tools utilized to test for these viruses are quite sensitive however, and are limited to primarily research investigations. Associations between virus and other gastrointestinal diseases have been evaluated as well, as have the host factors contributing to susceptibility to these infections.

SUMMARY

Viral gastroenteritis is common, and specific viruses are difficult to identify. Testing of these viruses through PCR or electron microscopy as a research tool is important, as is recognition of host risk factors, epidemiologic issues, and development of prevention and treatment strategies by identifying virus transmission.