Identification of risk factors associated with nosocomial infection by rotavirus P4G2, in a neonatal unit of a tertiary-care hospital

Epidemiology of group A rotavirus in children under five years of age with gastroenteritis in N'Djamena, Chad

BACKGROUND

Group A Rotaviruses (RVA) is one of the most common causes of severe diarrhoea in infants and children under 5 years of age. Unlike many countries in the world where RVA surveillance/control is active, in Chad , there is currently no applied RVA immunization program and surveillance strategy. The present study aims to determine the prevalence and associated risk factors of RVA gastroenteritis among children under five years of age in N'Djamena.

METHOD

This study comprised two parts: (1) A cross-sectional study carried in four hospitals in N'Djamena between August and November 2019, to determine infection risk factors and evidence of RVA infection among children aged five and below, consulted or hospitalized for diarrhea. An ELISA based RVA VP6 protein detection was used to determine RVA infection prevalence. Infection results and sociodemographic data were statistically analysed to determine RVA infection risk factors. (2) A retrospective study that consisted of analysing the records of stool examinations of the period from January 2016 to December 2018, to determine the prevalence of infectious gastroenteritis among the target population.

RESULTS

For the cross-sectional study, RVA infection prevalence was 12.76% (18/141) with males (61.11%) being more affected (sex ratio: 1.57). Children below 12 months were the most affected age group (44.44%) and 44.4% were malnourished. The mean Vesikari score shows that 38.8% of children have a high severity level and 41.1% have a moderate level. For the retrospective study, 2,592 cases of gastroenteritis hospitalization were analysed; 980 out of 2,592 cases (37.81%) of hospitalization due to diarrhoea were due to diarrhoeagenic pathogens including Emtamoeba hystolitica, Gardia lamblia, Trichomonas hominis, Hymenolepis nana, Escherichia coli, Shigella spp, Proteus mirabilis, and Klebsiella oxytoca. Cases of diarrhoea with negative pathogen search were 1,612 cases (62.19%). The diarrhoea peak was observed during the dry seasons, and the age group under 11 months was the most affected was (57.3%).

CONCLUSION

This study describes the evidence of RVA infection among diarrhoeic children below five years of age in N'Djamena, thus indicates a serious health burden. Malnourishment younger age was the higher risk factor. Further studies are needed to determine the circulating strains prior to considering introduction of RVA vaccine and setup a routine rotavirus surveillance in Chad.

Persistence of G10P[11] neonatal rotavirus infections in southern India

Background:

Neonatal rotavirus infections are predominantly caused by distinct genotypes restricted to this age-group and are mostly asymptomatic.

Method:

Stool samples from neonates admitted for >48 h in neonatal intensive care units (NICUs) in Vellore (2014–2015) and Chennai (2015–2016) in southern India, and from neonates born at hospitals in Vellore but not admitted to NICUs (2015–2016) were tested for rotavirus by ELISA and genotyped by hemi-nested RT-PCR.

Results:

Of 791 neonates, 150 and 336 were recruited from Vellore and Chennai NICUs, and 305 were born in five hospitals in Vellore. Positivity rates in the three settings were 49.3% (74/150), 29.5% (99/336) and 54% (164/305), respectively. G10P[11] was the commonly identified genotype in 87.8% (65/74), 94.9% (94/99) and 98.2% (161/164) of the neonates in Vellore and Chennai NICUs, and those born at Vellore hospitals, respectively. Neonates delivered by lower segment cesarian section (LSCS) at Vellore hospitals, not admitted to NICUs, had a significantly higher odds of acquiring rotavirus infection compared to those delivered vaginally [p = 0.002, OR = 2.4 (1.4–4.3)].

Conclusions:

This report demonstrates the persistence of G10P[11] strain in Vellore and Chennai, indicating widespread neonatal G10P[11] strain in southern India and their persistence over two decades, leading to interesting questions about strain stability.

Rotavirus outbreak among adults in a university hospital in Germany

BACKGROUND

Rotaviruses are the main cause of acute viral gastroenteritis in children under five years of age. Adults seem to be less frequently affected by rotaviruses most likely due to partial immunity resulting from prior infections.

OBJECTIVES

To describe a hospital-associated outbreak of rotavirus infections among adults.

STUDY DESIGN

Routine diagnostics and contact screening of symptomatic patients hospitalized at the university hospital of Freiburg. For rotavirus-positive patients, we performed rotavirus genotyping of all rotavirus RT-PCR positive samples and phylogenetic analysis.

RESULTS

Between December 2016 and April 2017 routine diagnostics showed an unexpectedly high number of rotavirus infections among adults with the exception of one pediatric case. In total, 32 temporal-associated cases were identified. Among these, two asymptomatic cases were detected. Genotyping showed that all isolates belonged to rotavirus G2P[4]. Phylogenetic analysis confirmed an outbreak. Infection prevention and control successfully contained further spread.

CONCLUSIONS

Infections with rotavirus are rare among adults but may spread between patients making timely recognition of rotavirus infections important for infection control. Rapid phylogenetic analysis is crucial for proactive infection control.

Bla-OXA48 gene microorganisms outbreak, in a tertiary Children's Hospital, Over 3 years (2012-2014): Case Report

RATIONALE

Carbapenem-resistant Enterobacteriaceae are an emerging problem in children. Nosocomial spread remains the principal risk factor for acquisition of these microorganisms.

PATIENTS CONCERNS

We describe an outbreak of Klebsiella pneumoniae OXA48 (KOXA48) in a tertiary children's hospital during the years 2012 to 2014, as well as the preventive measures put in place in colonized and infected cases.

DIAGNOSES

We studied, "in vitro," the KOXA48 susceptibility to antiseptics and surface disinfectants. Moreover, an epidemiological surveillance of infection or colonization by these microorganisms, with molecular typing of the KOXA48, was performed, and carbapenemase genes were confirmed by polymerase chain reaction (PCR).

INTERVENTIONS

The bundles recommended (early detection, cohorting of children and health care workers [HCW], contact precautions, etc.) to control the KOXA48 outbreak were taken from those described in the centers for disease control (CDC) 2012 guide, and adapted according to our experience in controlling other outbreaks.

OUTCOMES

All the KOXA48 microorganisms isolated from children belonged to the same strain (ST11) and were susceptible to alcohol solutions but not the surface disinfectant previously employed in our hospital (tensoactive). We reinforced the surface disinfection using a double application (tensoactive + alcohol). The outbreak of KOXA48 begun in 2012 (16 cases in neonatal intensive care unit [NICU] and 1 in pediatric intensive care unit [PICU]) ended before the end of the same year and was not transmitted to new patients in 2013 to 2014, despite readmission of some colonized cases, in intensive care units (ICUs) and other units, of our children hospital.

LESSONS

Infected children are the tip of the iceberg (3/17) of KOXA48 prevalence making it necessary to identify the cases colonized by these bacteria. At the beginning of the outbreak, the susceptibility of the epidemic strain to antiseptics and surface disinfectants should be studied. Moreover, the measures taken (cohorts, contact precautions, etc.) must be thorough in both colonized and infected cases, immediately, after microbiological diagnosis.

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.

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.

Targeted rotavirus vaccination of high-risk infants; a low cost and highly cost-effective alternative to universal vaccination

BACKGROUND

The cost-effectiveness of universal rotavirus (RV) vaccination is controversial in developed countries. As a result, RV vaccination programs do not currently exist in most European countries. Hospitalization is the main driver of RV disease costs, and prematurity, low birth weight (LBW) and underlying medical conditions have been associated with RV hospitalization and complications. We investigated the cost-effectiveness of targeted RV vaccination of high-risk infants and universal RV vaccination versus no vaccination.

METHODS

Disease burden, mortality and healthcare costs of RV hospitalization for children with and without prematurity, LBW and congenital pathology were quantified in two hospital-based observational studies in the Netherlands. Cost-effectiveness analysis was based on an age-structured stochastic multi-cohort model of the Dutch population comparing universal RV vaccination and targeted vaccination of high-risk infants to no vaccination. The primary endpoint was the incremental cost-effectiveness ratio (ICER), with a threshold of €35,000/quality-adjusted life year (QALY) from the healthcare provider perspective. Sensitivity analyses included vaccine price and coverage, herd-immunity and QALY losses.

RESULTS

A total of 936 children with RV infection were included. Prematurity, LBW and congenital pathology were associated with increased risks of RV hospitalization (relative risks (RR) ranging from 1.6 to 4.4), ICU admission (RR ranging from 4.2 to 7.9), prolonged hospital stay (1.5 to 3.0 excess days) and higher healthcare costs (€648 to €1,533 excess costs). Seven children succumbed due to RV complications, all belonging to the high-risk population. Targeted RV vaccination was highly cost-effective and potentially cost-saving from the healthcare provider perspective with ICERs below €20,000/QALY in all scenarios with total (undiscounted) annual healthcare costs between -€0.1 and €0.5 million/year. Results were most sensitive to mortality rates, but targeted vaccination remained highly cost-effective up to reductions of 90% compared to observed mortality. Universal RV vaccination was not considered cost-effective (mean ICER: €60,200/QALY) unless herd-immunity and caretaker QALY losses were included and vaccine prices were €60 at most (mean ICER: €21,309/QALY).

CONCLUSION

We recommend targeted RV vaccination for high-risk infants in developed countries.

Burden of community-acquired and nosocomial rotavirus gastroenteritis in the pediatric population of Western Europe: a scoping review

BACKGROUND

Rotavirus affects 95% of children worldwide by age 5 years and is the leading cause of severe dehydrating diarrhea. The objective of this review was to estimate the burden of rotavirus gastroenteritis (RVGE) in the Western European pediatric population.

METHODS

A comprehensive literature search (1999-2010) was conducted in PubMed and other sources (CDC; WHO, others). Data on the epidemiology and burden of RVGE among children < 5 years-old in Western Europe --including hospital-acquired disease--were extracted.

RESULTS

76 studies from 16 countries were identified. The mean percentage of acute gastroenteritis (AGE) cases caused by rotavirus ranged from 25.3%-63.5% in children < 5 years of age, peaking during winter. Incidence rates of RVGE ranged from 1.33-4.96 cases/100 person- years. Hospitalization rates for RVGE ranged from 7% to 81% among infected children, depending on the country. Nosocomial RVGE accounted for 47%-69% of all hospital-acquired AGE and prolonged hospital stays by 4-12 days. Each year, RVGE incurred $0.54- $53.6 million in direct medical costs and $1.7-$22.4 million in indirect costs in the 16 countries studied. Full serotyping data was available for 8 countries. G1P[8], G2P[4], G9P[8], and G3P[8] were the most prevalent serotypes (cumulative frequency: 57.2%- 98.7%). Serotype distribution in nosocomial RVGE was similar.

CONCLUSIONS

This review confirms that RVGE is a common disease associated with significant morbidity and costs across Western Europe. A vaccine protecting against multiple serotypes may decrease the epidemiological and cost burden of RVGE in Western Europe.

The coincidence of necrotizing enterocolitis and rotavirus infections and potential associations with cytokines

BACKGROUND

Necrotizing enterocolitis (NEC) is the most common gastrointestinal disease in neonatal intensive care units. Although the pathogenesis of NEC remains unclear, evidence suggests that infections, especially bacterial infections, may play an important role. Viral infections may also result in NEC. Several outbreaks of NEC associated with rotaviruses have been described previously.

OBJECTIVE

To investigate the association between rotavirus (RV) and serum interleukin (IL)-6 and IL-8 levels in infants with NEC.

METHODS

RV infections were prospectively studied using antigen detection in the stools of 31 infants with NEC. Additionally, serum levels of IL-6, IL-8 and tumour necrosis factor-alpha were tested using micro-ELISA at 0 h and 48 h after diagnosis of NEC.

RESULTS

Fecal specimens from 13 infants were positive, while fecal specimens from 18 infants were negative for RV according to antigen detection (RV+ and RV- groups, respectively). The mortality rate and the severity of NEC were not significantly different between the RV+ and RV- groups. IL-6 levels at 0 h and 48 h after diagnosis of NEC in RV+ infants were lower compared with RV- infants, while IL-8 levels were greater at 0 h and 48 h after diagnosis of NEC in RV+ infants compared with RV- infants.

CONCLUSION

A high prevalence of RV infection in neonates with NEC was found. Decreased IL-6 levels and increased IL-8 and tumour necrosis factor-alpha levels in RV+ neonates with NEC suggests a role for RV in 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.