Globally, norovirus is associated with approximately one-fifth of all diarrhea cases, with similar prevalence in both children and adults, and is estimated to cause over 200,000 deaths annually in ...developing countries. Norovirus is an important pathogen in a number of high-priority domains: it is the most common cause of diarrheal episodes globally, the principal cause of foodborne disease outbreaks in the United States, a key health care-acquired infection, a common cause of travel-associated diarrhea, and a bane for deployed military troops. Partly as a result of this ubiquity and burden across a range of different populations, identifying target groups and strategies for intervention has been challenging. And, on top of the breadth of this public health problem, there remain important gaps in scientific knowledge regarding norovirus, especially with respect to disease in low-income settings. Many pathogens can cause acute gastroenteritis. Historically, rotavirus was the most common cause of severe disease in young children globally. Now, vaccines are available for rotavirus and are universally recommended by the World Health Organization. In countries with effective rotavirus vaccination programs, disease due to that pathogen has decreased markedly, but norovirus persists and is now the most common cause of pediatric gastroenteritis requiring medical attention. However, the data supporting the precise role of norovirus in low- and middle-income settings are sparse. With vaccines in the pipeline, addressing these and other important knowledge gaps is increasingly pressing. We assembled an expert group to assess the evidence for the global burden of norovirus and to consider the prospects for norovirus vaccine development. The group assessed the evidence in the areas of burden of disease, epidemiology, diagnostics, disease attribution, acquired immunity, and innate susceptibility, and the group considered how to bring norovirus vaccines from their current state of development to a viable product that will benefit global health.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The successful development and implementation of rotavirus vaccines will have a significant impact on rotavirus- induced gastroenteritis in children worldwide. However, this introduction will ...increase the immune pressure against wild-type rotavirus strains circulating in the community, altering the forces and balances that drive rotavirus evolution. There is concern that antigenically distinct novel or rare strains may be selected and spread, decreasing vaccine efficacy. This review describes the diversity of rotavirus strains and the mechanism by which wild-type rotavirus strains can evolve, including genetic drift and genetic reassortment.
Worldwide, approximately 1.8 million children die from diarrhea annually, and millions more suffer multiple episodes of nonfatal diarrhea. On average, in up to 40% of cases, no etiologic agent can be ...identified. The advent of metagenomic sequencing has enabled systematic and unbiased characterization of microbial populations; thus, metagenomic approaches have the potential to define the spectrum of viruses, including novel viruses, present in stool during episodes of acute diarrhea. The detection of novel or unexpected viruses would then enable investigations to assess whether these agents play a causal role in human diarrhea. In this study, we characterized the eukaryotic viral communities present in diarrhea specimens from 12 children by employing a strategy of "micro-mass sequencing" that entails minimal starting sample quantity (<100 mg stool), minimal sample purification, and limited sequencing (384 reads per sample). Using this methodology we detected known enteric viruses as well as multiple sequences from putatively novel viruses with only limited sequence similarity to viruses in GenBank.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Current and new rotavirus vaccines Burke, Rachel M; Tate, Jacqueline E; Kirkwood, Carl D ...
Current opinion in infectious diseases,
2019-October, Letnik:
32, Številka:
5
Journal Article
Recenzirano
Odprti dostop
PURPOSE OF REVIEWAs of 2019, four rotavirus vaccines have been prequalified by the WHO for use worldwide. This review highlights current knowledge regarding rotavirus vaccines available, and provides ...a brief summary of the rotavirus vaccine pipeline.
RECENT FINDINGSData generated from use of currently available products supports their effectiveness and impact in diverse settings. Rotavirus vaccines have a favorable risk–benefit profile, but previous associations of rotavirus vaccination with intussusception necessitate continued monitoring for this rare but serious adverse event. Implementation of rotavirus vaccines was jeopardized in late 2018 and 2019 by a shortage of vaccine supply. Fortunately, with the prequalification of two additional vaccines in 2018, countries have increased choice in products with different characteristics, pricing, and implementation strategies. Other vaccines currently in development may open up further immunization strategies, such as neonatal vaccination schedules or parenteral administration.
SUMMARYRotavirus vaccines have demonstrated impact in reducing diarrheal morbidity and mortality worldwide. As countries begin to introduce the newly prequalified vaccines, additional data will become available on the safety and effectiveness of those products. Products in the pipeline have distinct profiles and could be an essential part of the expansion of rotavirus vaccine use worldwide.
Introduction of rotavirus vaccines into national immunization programs (NIPs) could result in strain selection due to vaccine-induced selective pressure. This study describes the distribution and ...diversity of rotavirus genotypes before and after rotavirus vaccine introduction into the Australian NIP. State-based vaccine selection facilitated a unique comparison of diversity in RotaTeq and Rotarix vaccine states.
From 1995 to 2015, the Australian Rotavirus Surveillance Program conducted genotypic analysis on 13051 rotavirus-positive samples from children <5 years of age, hospitalized with acute gastroenteritis. Rotavirus G and P genotypes were determined using serological and heminested multiplex reverse-transcription polymerase chain reaction assays.
G1P8 was the dominant genotype nationally in the prevaccine era (1995-2006). Following vaccine introduction (2007-2015), greater genotype diversity was observed with fluctuating genotype dominance. Genotype distribution varied based on the vaccine implemented, with G12P8 dominant in states using RotaTeq, and equine-like G3P8 and G2P4 dominant in states and territories using Rotarix.
The increased diversity and differences in genotype dominance observed in states using RotaTeq (G12P8), and in states and territories using Rotarix (equine-like G3P8 and G2P4), suggest that these vaccines exert different immunological pressures that influence the diversity of rotavirus strains circulating in Australia.
During 2013, a novel equine-like G3P8 rotavirus emerged as the dominant strain in Australian children with severe rotavirus gastroenteritis. Full genome analysis demonstrated that the strain was an ...inter-genogroup reassortant, containing an equine-like G3 VP7, a P8 VP4 and a genogroup 2 backbone I2-R2-C2-M2-A2-N2-T2-E2-H2. The genome constellation of the equine-like G3P8 was distinct to Australian and global G3P8 strains. Phylogenetic analysis demonstrated a genetic relationship to multiple gene segments of Japanese strains RVA/JPN/S13-30/2013/G3P4 and RVA/Human-wt/JPN/HC12016/2012/G1P8. The Australian equine-like G3P8 strain displayed a distinct VP7 antigenic profile when compared with the previously circulating Australian G3P8 strains. Identification of similar genes in strains from several geographical regions suggested the equine-like G3P8 strain was derived by multiple reassortment events between globally co-circulating strains from both human and animal sources. This study reinforces the dynamic nature of rotavirus strains and illustrates the potential for novel human/animal reassortant strains to emerge within the human population.
The intestinal microbiota is involved in the pathogenesis of inflammatory bowel disease. A reduction in the diversity of the intestinal microbiota as well as specific taxonomic and functional shifts ...have been reported in Crohn's disease and may play a central role in the inflammatory process. The aim was to systematically review recent developments in the structural and functional changes observed in the gastrointestinal microbiome in patients with Crohn's Disease.
Seventy-two abstracts were included in this review. The effects of host genetics, disease phenotype, and inflammatory bowel disease treatment on the gastrointestinal microbiome in Crohn's disease were reviewed, and taxonomic shifts in patients with early and established disease were described. The relative abundance of Bacteroidetes is increased and Firmicutes decreased in Crohn's disease compared with healthy controls. Enterobacteriaceae, specifically Eschericia coli, is enriched in Crohn's disease. Faecalibacterium prausnitzii is found at lower abundance in Crohn's disease and in those with postoperative recurrence. Observed functional changes include major shifts in oxidative stress pathways, a decrease in butanoate and propanoate metabolism gene expression, lower levels of butyrate, and other short-chain fatty acids, decreased carbohydrate metabolism, and decreased amino acid biosynthesis.
Changes in microbial composition and function have been described, although a causative role remains to be established. Larger, prospective, and longitudinal studies are required with deep interrogation of the microbiome if causality is to be determined, and refined microbial manipulation is to emerge as a focused therapy.
Hepatitis E virus (HEV) is the most common cause of acute hepatitis. While symptoms are generally mild and resolve within weeks, some populations (e.g., pregnant women, immunocompromised adults) are ...at high-risk of severe HEV-related morbidity and mortality. There has not been a recent comprehensive review of contemporary HEV outbreaks, which limits the validity of current disease burden estimates. Therefore, we aimed to characterize global HEV outbreaks and describe data gaps to inform HEV outbreak prevention and response initiatives.
We performed a systematic review of peer-reviewed (PubMed, Embase) and gray literature (ProMED) to identify reports of outbreaks published between 2011 and 2022. We included (1) reports with ≥ 5 cases of HEV, and/or (2) reports with 1.5 times the baseline incidence of HEV in a specific population, and (3) all reports with suspected (e.g., clinical case definition) or confirmed (e.g., ELISA or PCR test) cases if they met criterium 1 and/or 2. We describe key outbreak epidemiological, prevention and response characteristics and major data gaps.
We identified 907 records from PubMed, 468 from Embase, and 247 from ProMED. We screened 1,362 potentially relevant records after deduplication. Seventy-one reports were synthesized, representing 44 HEV outbreaks in 19 countries. The populations at risk, case fatalities, and outbreak durations were not reported in 66% of outbreak reports. No reports described using HEV vaccines. Reported intervention efforts included improving sanitation and hygiene, contact tracing/case surveillance, chlorinating boreholes, and advising residents to boil water. Commonly missing data elements included specific case definitions used, testing strategy and methods, seroprevalence, impacts of interventions, and outbreak response costs. Approximately 20% of HEV outbreaks we found were not published in the peer-reviewed literature.
HEV represents a significant public health problem. Unfortunately, extensive data shortages and a lack of standardized reporting make it difficult to estimate the HEV disease burden accurately and to implement effective prevention and response activities. Our study has identified major gaps to guide future studies and outbreak reporting systems. Our results support the development of standardized reporting procedures/platforms for HEV outbreaks to ensure accurate and timely data distribution, including active and passive coordinated surveillance systems, particularly among high-risk populations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK