ABSTRACT
OBJECTIVE: Studies involving less sensitive conventional microscopy and culture-based approaches have identified distinct differences in diarrhoeal aetiology in childhood malnutrition. Our study involved the use of an advanced molecular biology technique, the TaqMan Array Cards (TAC), to elucidate the diarrhoeal aetiology among young infants with severe acute malnutrition (SAM). METHOD: A total of 113 faecal samples was collected from SAM infants, aged 2-6 months, upon admission to the Dhaka Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) with complications of diarrhoea and related comorbidities. We used TAC for the detection of 29 different diarrhoeal enteropathogens from a single faecal sample. For comparison, we also analysed 25 diarrhoeal samples from well-nourished infants of similar age. RESULTS: Higher odds of detection of all bacterial enteropathogens were associated with diarrhoea among SAM infants. In particular, the detection of Aeromonas sp (aOR: 25.7, p = 0.011), Campylobacter sp (aOR: 9.6, p < 0.01) and ETEC (aOR: 5.2, p = 0.022) was significantly associated with diarrhoea among SAM infants in comparison to well-nourished infants. 80% higher odds of detection of rotavirus and norovirus GII were associated with diarrhoea among well-nourished infants in comparison to SAM infants (aOR: 0.2, p < 0.05). CONCLUSION: Our study findings demonstrate a difference in diarrhoeal aetiology among SAM and well-nourished young infants, which may be useful in providing an evidence-based logic for possible revision of treatment guidelines for treatment of young diarrhoeal infants with SAM in the early management of the menace of antimicrobial resistance.
Subject(s)
Bacterial Infections/diagnosis , Diarrhea, Infantile/diagnosis , Diarrhea, Infantile/microbiology , Infant Nutrition Disorders/complications , Severe Acute Malnutrition/complications , Bacteria/classification , Bacteria/isolation & purification , Bacterial Infections/epidemiology , Bacterial Infections/microbiology , Bangladesh/epidemiology , Diarrhea, Infantile/epidemiology , Female , Humans , Infant , Infant Nutrition Disorders/epidemiology , Male , Severe Acute Malnutrition/epidemiologyABSTRACT
OBJECTIVES: To evaluate the effect of bovine colostrum (BC) on the treatment of children with acute diarrhea attending the outpatient clinic. METHODS: This double-blind randomized controlled trial was conducted on 160 children with diarrhea; 80 cases were randomly treated with BC group and 80 cases randomly received placebo (placebo group). All cases were investigated for bacterial causes of diarrhea (Salmonella spp, Shigella spp, diarrheagenic E. coli (DEC), Campylobacter spp., and Vibrio cholerae) as well as for Rotavirus antigen in stool. RESULTS: After 48 h, the BC group had a significantly lower frequency of vomiting, diarrhea and Vesikari scoring compared with the placebo group (p = 0.000, p = 0.000, p = 0.000, respectively), whether it was due to Rotavirus or E. coli infection. CONCLUSIONS: BC is effective in the treatment of acute diarrhea and can be considered as adjuvant therapy in both viral and bacterial diarrhea to prevent diarrhea-related complications.
Subject(s)
Colostrum , Diarrhea, Infantile/therapy , Acute Disease , Animals , Antigens, Viral/analysis , Breast Feeding , Cattle , Child, Preschool , Diarrhea, Infantile/microbiology , Diarrhea, Infantile/virology , Double-Blind Method , Escherichia coli/isolation & purification , Escherichia coli Infections/complications , Feces/microbiology , Feces/virology , Female , Humans , Infant , Infant Formula , Male , Rotavirus/isolation & purification , Rotavirus Infections/complicationsABSTRACT
OBJECTIVE: Enteric bacterial pathogens cause diarrheal disease and mortality at significant rates throughout the world, particularly in children younger than 5 years. Our ability to combat bacterial pathogens has been hindered by antibiotic resistance, a lack of effective vaccines, and accurate models of infection. With the renewed interest in bacteriophage therapy, we sought to use a novel human intestinal model to investigate the efficacy of a newly isolated bacteriophage against Shigella flexneri. METHODS: An S. flexneri 2457T-specific bacteriophage was isolated and assessed through kill curve experiments and infection assays with colorectal adenocarcinoma HT-29 cells and a novel human intestinal organoid-derived epithelial monolayer model. In our treatment protocol, organoids were generated from intestinal crypt stem cells, expanded in culture, and seeded onto transwells to establish 2-dimensional monolayers that differentiate into intestinal cells. RESULTS: The isolated bacteriophage efficiently killed S. flexneri 2457T, other S. flexneri strains, and a strain of 2457T harboring an antibiotic resistance cassette. Analyses with laboratory and commensal Escherichia coli strains demonstrated that the bacteriophage was specific to S. flexneri, as observed under co-culture conditions. Importantly, the bacteriophage prevented both S. flexneri 2457T epithelial cell adherence and invasion in both infection models. CONCLUSIONS: Bacteriophages offer feasible alternatives to antibiotics for eliminating enteric pathogens, confirmed here by the bacteriophage-targeted killing of S. flexneri. Furthermore, application of the organoid model has provided important insight into Shigella pathogenesis and bacteriophage-dependent intervention strategies. The screening platform described herein provides proof-of-concept analysis for the development of novel bacteriophage therapies to target antibiotic-resistant pathogens.
Subject(s)
Diarrhea, Infantile/therapy , Escherichia coli , Intestines/microbiology , Phage Therapy , Shigella flexneri , Child , Diarrhea, Infantile/microbiology , Female , HT29 Cells , Humans , Infant , Infant, Newborn , MaleABSTRACT
OBJECTIVES: The determinants of gut microbiota composition and its effects on common childhood illnesses are only partly understood, especially in low-income settings. The aim of the present study was to investigate whether morbidity predicts gut microbiota composition in Malawian children and whether microbiota predicts subsequent morbidity. We tested the hypothesis that common infectious disease symptoms would be predictive of lower microbiota maturity and diversity. METHODS: We used data from 631 participants in a randomized-controlled nutrition intervention trial, in which a small-quantity lipid-based nutrient supplement was provided to pregnant and lactating mothers and their children at 6 to 18 months of age. Fecal samples were collected from the children at 6, 12, 18, and 30 months of age and analyzed using 16S rRNA sequencing. Microbiota variables consisted of measures of microbiota diversity (Shannon Index), microbiota maturity (microbiota-for-age z score), and the relative abundances of taxa. Morbidity variables included gastrointestinal and respiratory symptoms and fever. RESULTS: Diarrhea and respiratory symptoms from 11 to 12 months were predictive of lower microbiota-for-age z score and higher Shannon Index, respectively (Pâ=â0.035 and Pâ=â0.023). Morbidity preceding sample collection was predictive of the relative abundances of several bacterial taxa at all time points. Higher microbiota maturity and diversity at 6 months were predictive of a lower incidence rate of fever in the subsequent 6 months (Pâ=â0.007 and Pâ=â0.031). CONCLUSIONS: Our findings generally do not support the hypothesis that morbidity prevalence predicts a subsequent decrease in gut microbiota maturity or diversity in rural Malawian children. Certain morbidity symptoms may be predictive of microbiota maturity and diversity and relative abundances of several bacterial taxa. Furthermore, microbiota diversity and maturity may be associated with the subsequent incidence of fever.
Subject(s)
Diarrhea, Infantile/epidemiology , Gastrointestinal Tract/microbiology , Respiratory Tract Infections/epidemiology , Diarrhea, Infantile/microbiology , Female , Humans , Infant , Malawi/epidemiology , Male , Maternal-Child Health Services , Microbiota/genetics , Prevalence , Prospective Studies , RNA, Ribosomal, 16S/genetics , Rural PopulationABSTRACT
OBJECTIVES: This study aimed to trace the transmission source of Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Enteritidis strains associated with enteric infections in Shanghainese children, and understand the molecular mechanism of resistance to third-generation cephalosporins and ciprofloxacin. MATERIALS AND METHODS: The profiles of pulsed-field gel electrophoresis (PFGE) were compared among the isolates from children, animal, and environment. Antimicrobial susceptibility was determined using the minimal inhibitory concentrations and Kirby-Bauer disk diffusion method. Extended-spectrum ß-lactamase (ESBL) producing isolates mediated by resistance genes were identified using polymerase chain reaction and sequencing. RESULTS: Based on PFGE patterns, 49 (33.1%) of 148 human Salmonella Typhimurium isolates located in the dominant PFGE clusters were genetically related to the isolates from poultry source, environment water, aquatic products, and reptiles, whereas 97 (97.0%) of 100 human Salmonella Enteritidis isolates were genetically related to isolates from poultry and water. The rates of resistance to ceftriaxone among clinical Salmonella Typhimurium and Salmonella Enteritidis isolates were 42.0% and 14.2%, respectively. Besides, 35.1% of Salmonella Typhimurium isolates displayed resistance to ciprofloxacin; 64.9% of Salmonella Typhimurium isolates and 97.0% of Salmonella Enteritidis isolates displayed reduced susceptibility to ciprofloxacin. Of 64 ESBL/AmpC-producing strains, CTX-M, TEM, DHA, and CMY were detected at frequencies of 86.0%, 62.5%, 7.8%, 3.1%, and 3.1%, respectively. CONCLUSIONS: The transmission sources of Salmonella Typhimurium and Salmonella Enteritidis infections in Shanghainese children were diverse. The high prevalence of resistance to third-generation cephalosporins and ciprofloxacin mediated by multiple molecular mechanisms needs continuous monitoring and intervention.
Subject(s)
Diarrhea, Infantile/microbiology , Food Microbiology , Salmonella Infections/epidemiology , Salmonella enteritidis/isolation & purification , Salmonella typhimurium/isolation & purification , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Ceftriaxone/pharmacology , Ceftriaxone/therapeutic use , Child , Child Health Services , Child, Preschool , China/epidemiology , Ciprofloxacin/pharmacology , Ciprofloxacin/therapeutic use , Contact Tracing , Disk Diffusion Antimicrobial Tests , Drug Resistance, Multiple, Bacterial/genetics , Female , Humans , Infant , Male , Salmonella Infections/drug therapy , Salmonella Infections/microbiology , Salmonella Infections/transmission , Salmonella enteritidis/drug effects , Salmonella enteritidis/genetics , Salmonella typhimurium/drug effects , Salmonella typhimurium/geneticsABSTRACT
BACKGROUND: The impacts of climate change on surface water, waterborne disease, and human health remain a growing area of concern, particularly in Africa, where diarrheal disease is one of the most important health threats to children under 5 years of age. Little is known about the role of surface water and annual flood dynamics (flood pulse) on waterborne disease and human health nor about the expected impact of climate change on surface-water-dependent populations. METHODS AND FINDINGS: Using the Chobe River in northern Botswana, a flood pulse river-floodplain system, we applied multimodel inference approaches assessing the influence of river height, water quality (bimonthly counts of Escherichia coli and total suspended solids [TSS], 2011-2017), and meteorological variability on weekly diarrheal case reports among children under 5 presenting to health facilities (n = 10 health facilities, January 2007-June 2017). We assessed diarrheal cases by clinical characteristics and season across age groups using monthly outpatient data (January 1998-June 2017). A strong seasonal pattern was identified, with 2 outbreaks occurring regularly in the wet and dry seasons. The timing of outbreaks diverged from that at the level of the country, where surface water is largely absent. Across age groups, the number of diarrheal cases was greater, on average, during the dry season. Demographic and clinical characteristics varied by season, underscoring the importance of environmental drivers. In the wet season, rainfall (8-week lag) had a significant influence on under-5 diarrhea, with a 10-mm increase in rainfall associated with an estimated 6.5% rise in the number of cases. Rainfall, minimum temperature, and river height were predictive of E. coli concentration, and increases in E. coli in the river were positively associated with diarrheal cases. In the dry season, river height (1-week lag) and maximum temperature (1- and 4-week lag) were significantly associated with diarrheal cases. During this period, a 1-meter drop in river height corresponded to an estimated 16.7% and 16.1% increase in reported diarrhea with a 1- and 4-week lag, respectively. In this region, as floodwaters receded from the surrounding floodplains, TSS levels increased and were positively associated with diarrheal cases (0- and 3-week lag). Populations living in this region utilized improved water sources, suggesting that hydrological variability and rapid water quality shifts in surface waters may compromise water treatment processes. Limitations include the potential influence of health beliefs and health seeking behaviors on data obtained through passive surveillance. CONCLUSIONS: In flood pulse river-floodplain systems, hydrology and water quality dynamics can be highly variable, potentially impacting conventional water treatment facilities and the production of safe drinking water. In Southern Africa, climate change is predicted to intensify hydrological variability and the frequency of extreme weather events, amplifying the public health threat of waterborne disease in surface-water-dependent populations. Water sector development should be prioritized with urgency, incorporating technologies that are robust to local environmental conditions and expected climate-driven impacts. In populations with high HIV burdens, expansion of diarrheal disease surveillance and intervention strategies may also be needed. As annual flood pulse processes are predominantly influenced by climate controls in distant regions, country-level data may be inadequate to refine predictions of climate-health interactions in these systems.
Subject(s)
Climate Change , Diarrhea, Infantile/microbiology , Disease Outbreaks , Escherichia coli Infections/microbiology , Escherichia coli/pathogenicity , Floods , Rivers/microbiology , Water Microbiology , Water Quality , Water Supply , Weather , Age Factors , Botswana/epidemiology , Child, Preschool , Diarrhea, Infantile/diagnosis , Diarrhea, Infantile/epidemiology , Escherichia coli/isolation & purification , Escherichia coli Infections/diagnosis , Escherichia coli Infections/epidemiology , Escherichia coli Infections/transmission , Female , Humans , Infant , Male , Public Health , Retrospective Studies , Risk Factors , SeasonsABSTRACT
PURPOSE OF REVIEW: Campylobacter jejuni is recognized as one of the most common causes of food-borne gastrointestinal illness worldwide, resulting in a self-limiting dysentery in developed countries. However, it is increasingly gaining attention due to its association with postinfectious complications such as Guillain-Barré Syndrome and recently recognized importance in early childhood diarrhea in developing countries. We hypothesize that the inflammation mediated by C. jejuni infection causes environmental enteric dysfunction, and with contribution from diet and the host, microbiome may be responsible for growth faltering in children and developmental disability. RECENT FINDINGS: Diet plays a major role in the impact of C. jejuni infection, both by availability of micronutrients for the bacteria and host as well as shaping the microbiome that affords resistance. Early childhood repeated exposure to the bacterium results in inflammation that affords long-term immunity but, in the short term, can lead to malabsorption, oral vaccine failure, cognitive delay and increased under-5 mortality. SUMMARY: As interest in C. jejuni increases, our understanding of its virulence mechanisms has improved. However, much work remains to be done to fully understand the implications of immune-mediated inflammation and its potential role in diseases such as environmental enteric dysfunction.
Subject(s)
Campylobacter Infections/immunology , Campylobacter jejuni/immunology , Developing Countries , Diarrhea, Infantile/microbiology , Campylobacter Infections/complications , Campylobacter jejuni/pathogenicity , Diarrhea, Infantile/immunology , Gastrointestinal Microbiome , Growth Disorders/microbiology , Humans , InfantABSTRACT
BACKGROUND & OBJECTIVES: Multidrug-resistant enteropathogenic Escherichia coli (EPEC) is responsible for a large number of cases of infantile diarrhoea in developing countries, causing failure in treatment with consequent health burden and resulting in a large number of deaths every year. This study was undertaken to determine the proportion of typical and atypical EPEC in under five children with diarrhoea and controls, their function as a carriage and to identify virulent genes associated with them. METHODS: During the study period, 120 stool samples including 80 from controls children were collected and analyzed for the presence of EPEC using standard bacteriological methods. Isolates were subjected to antimicrobial testing by disc diffusion method. Isolates confirmed as E. coli by phenotypic method were further tested for the presence of attaching and effacing (eae) and bundle-forming pilus (bfpA) genes by real-time SYBR Green-based polymerase chain reaction. RESULTS: All isolates were tested for the presence of EPEC. The frequency of typical EPEC was 20 and 16.25 per cent whereas the frequency of atypical EPEC strains was 5 and 23.75 per cent in patients and controls, respectively (PbfpA was seen in 45 and 18.75 per cent isolates of diarrhoeal patients and controls, respectively. INTERPRETATION & CONCLUSIONS: Our results showed that typical EPEC was a common cause of diarrhoea, but at the same time, atypical EPEC was emerging as colonizers in the intestine of children with and without diarrhoea in and around Delhi. Children can be considered asymptomatic carriers of these pathogens and can transmit them to other susceptible children. Adequate steps need to be taken to stop these strains from developing and spreading further.
Subject(s)
Adhesins, Bacterial/genetics , Diarrhea, Infantile/diagnosis , Escherichia coli Infections/diagnosis , Escherichia coli Proteins/genetics , Fimbriae Proteins/genetics , Adhesins, Bacterial/isolation & purification , Child , Child, Preschool , Diarrhea, Infantile/epidemiology , Diarrhea, Infantile/genetics , Diarrhea, Infantile/microbiology , Enteropathogenic Escherichia coli/genetics , Enteropathogenic Escherichia coli/pathogenicity , Escherichia coli Infections/genetics , Escherichia coli Infections/microbiology , Escherichia coli Proteins/isolation & purification , Female , Fimbriae Proteins/isolation & purification , Humans , India/epidemiology , Infant , MaleABSTRACT
BACKGROUND: Diarrhoeagenic Escherichia coli (DEC) pathotypes are among the most common bacterial causes of morbidity and mortality in young children. These pathogens are not sought routinely and capacity for their detection is limited in Africa. We investigated the distribution and dissemination of DEC in 126 children paired with their mothers in a Nigerian community. METHODS: A total of 861 E. coli were isolated from 126 children with diarrhoea and their mothers. Antimicrobial susceptibility of each isolate was determined by Kirby-Bauer disc diffusion technique. All the isolates were screened for DEC markers by multiplex PCR. Genetic relatedness of DEC strains was determined by flagellin typing and Insertion element 3 (IS3)-based PCR. RESULTS: DEC were identified from 35.7% of individuals with the most common pathotype being shiga toxin-producing E. coli (42, 16.7%). Identical pathotypes were found in 13 (10.3%) of the mother-child pairs and in three of these strains from mothers and their children showed identical genetic signatures. Over 90% of DEC isolates were resistant to ampicillin, sulphonamide, tetracycline, streptomycin or trimethoprim, but only 9 (7.2%) were ciprofloxacin resistant CONCLUSION: The data suggest that healthy mothers are asymptomatic reservoirs of multiply-resistant strains that are pathogenic in their children and there are instances in which identical strains are found in mother-child pairs.
Subject(s)
Diarrhea, Infantile/microbiology , Diarrhea/microbiology , Escherichia coli Infections/microbiology , Escherichia coli/isolation & purification , Adolescent , Adult , Ampicillin , Anti-Bacterial Agents , Child, Preschool , Ciprofloxacin , DNA Transposable Elements , Disk Diffusion Antimicrobial Tests , Female , Humans , Infant , Infant, Newborn , Middle Aged , Mothers , Multiplex Polymerase Chain Reaction , Nigeria , Tetracycline , Young AdultABSTRACT
Diarrheal diseases are a major cause of childhood death in resource-poor countries, killing approximately 760,000 children younger than 5 years each year. Although deaths due to diarrhea have declined dramatically, high rates of stunting and malnutrition have persisted. Environmental enteric dysfunction (EED) is a subclinical condition caused by constant fecal-oral contamination with resultant intestinal inflammation and villous blunting. These histological changes were first described in the 1960s, but the clinical effect of EED is only just being recognized in the context of failure of nutritional interventions and oral vaccines in resource-poor countries. We review the existing literature regarding the underlying causes of and potential interventions for EED in children, highlighting the epidemiology, clinical and histologic classification of the entity, and discussing novel biomarkers and possible therapies. Future research priorities are also discussed.
Subject(s)
Diarrhea, Infantile/epidemiology , Environmental Exposure/adverse effects , Intestinal Diseases/epidemiology , Child Health , Child, Preschool , Diarrhea, Infantile/etiology , Diarrhea, Infantile/microbiology , Diarrhea, Infantile/prevention & control , Female , Global Health , Humans , Hygiene , Infant , Infant, Newborn , Intestinal Diseases/etiology , Intestinal Diseases/microbiology , Intestinal Diseases/prevention & control , Male , PovertyABSTRACT
Staphylococcus aureus is a well-known organism which is responsible for a variety of human infectious diseases including skin infections, pneumonia, bacteremia, and endocarditis. Few of the microorganisms can be transmitted from mother to the newborn or infant by milk breastfeeding. This study aims to identify transmission of S. aureus from healthy, lactating mothers to their infants by breastfeeding. Stool specimens of diarrheal infants and breast milk of their mother (totally three pairs) were collected and six Staphylococcus aureus isolates were cultured positively. Homology and molecular characters of isolated strains were tested using pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing. Furthermore, toxin genes detection was also performed. Each pair of isolates has the same PFGE type and spa type. Four Sequence types (STs) were found among all the isolates; they are ST15, ST188, and ST59, respectively. Among the strains, seb, sec, and tst genes were found, and all were negative for pvl gene. The homology of the S. aureus strains isolated from the infants' stool and the mothers' milk was genetically demonstrated, which indicated that breastfeeding may be important in the transmission of S. aureus infection, and the character of S. aureus needed to be further evaluated.
Subject(s)
Diarrhea, Infantile/microbiology , Milk, Human/microbiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/physiology , Adult , Breast Feeding/adverse effects , China , Diarrhea, Infantile/etiology , Feces/microbiology , Female , Humans , Infant , Infant, Newborn , Infectious Disease Transmission, Vertical , Male , Multilocus Sequence Typing , Staphylococcal Infections/etiology , Staphylococcal Infections/transmission , Staphylococcus aureus/classification , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purification , Young AdultABSTRACT
BACKGROUND: In-home iron fortification for infants in developing countries is recommended for control of anaemia, but low absorption typically results in >80% of the iron passing into the colon. Iron is essential for growth and virulence of many pathogenic enterobacteria. We determined the effect of high and low dose in-home iron fortification on the infant gut microbiome and intestinal inflammation. METHODS: We performed two double-blind randomised controlled trials in 6-month-old Kenyan infants (n=115) consuming home-fortified maize porridge daily for 4 months. In the first, infants received a micronutrient powder (MNP) containing 2.5â mg iron as NaFeEDTA or the MNP without iron. In the second, they received a different MNP containing 12.5â mg iron as ferrous fumarate or the MNP without the iron. The primary outcome was gut microbiome composition analysed by 16S pyrosequencing and targeted real-time PCR (qPCR). Secondary outcomes included faecal calprotectin (marker of intestinal inflammation) and incidence of diarrhoea. We analysed the trials separately and combined. RESULTS: At baseline, 63% of the total microbial 16S rRNA could be assigned to Bifidobacteriaceae but there were high prevalences of pathogens, including Salmonella Clostridium difficile, Clostridium perfringens, and pathogenic Escherichia coli. Using pyrosequencing, +FeMNPs increased enterobacteria, particularly Escherichia/Shigella (p=0.048), the enterobacteria/bifidobacteria ratio (p=0.020), and Clostridium (p=0.030). Most of these effects were confirmed using qPCR; for example, +FeMNPs increased pathogenic E. coli strains (p=0.029). +FeMNPs also increased faecal calprotectin (p=0.002). During the trial, 27.3% of infants in +12.5â mgFeMNP required treatment for diarrhoea versus 8.3% in -12.5â mgFeMNP (p=0.092). There were no study-related serious adverse events in either group. CONCLUSIONS: In this setting, provision of iron-containing MNPs to weaning infants adversely affects the gut microbiome, increasing pathogen abundance and causing intestinal inflammation. TRIAL REGISTRATION NUMBER: NCT01111864.
Subject(s)
Enterocolitis/chemically induced , Food, Fortified/adverse effects , Intestines/microbiology , Iron, Dietary/adverse effects , Microbiota/drug effects , Anemia, Iron-Deficiency/prevention & control , Bacteria/isolation & purification , Diarrhea, Infantile/chemically induced , Diarrhea, Infantile/microbiology , Dose-Response Relationship, Drug , Double-Blind Method , Enterocolitis/microbiology , Feces/chemistry , Humans , Infant , Iron, Dietary/administration & dosage , Iron, Dietary/pharmacology , Leukocyte L1 Antigen Complex/metabolism , Micronutrients/administration & dosage , Micronutrients/adverse effects , Micronutrients/pharmacologyABSTRACT
Conventionally, in Escherichia coli, phylogenetic groups A and B1 are associated with commensal strains while B2 and D are associated with extraintestinal strains. The aim of this study was to evaluate diarrheagenic (DEC) and commensal E. coli phylogeny and its association with antibiotic resistance and clinical characteristics of the diarrheal episode. Phylogenetic groups and antibiotic resistance of 369 E. coli strains (commensal strains and DEC from children with or without diarrhea) isolated from Peruvian children <1 year of age were determined by a Clermont triplex PCR and Kirby-Bauer method, respectively. The distribution of the 369 E. coli strains among the 4 phylogenetic groups was A (40%), D (31%), B1 (21%), and B2 (8%). DEC-control strains were more associated with group A while DEC-diarrhea strains were more associated with group D (P < 0.05). There was a tendency (P = 0.06) for higher proportion of persistent diarrhea (≥ 14 days) among severe groups (B2 and D) in comparison with nonsevere groups (A and B1). Strains belonging to group D presented significantly higher percentages of multidrug resistance than the rest of the groups (P > 0.01). In summary, DEC-diarrhea strains were more associated with group D than strains from healthy controls.
Subject(s)
Diarrhea, Infantile/microbiology , Escherichia coli Infections/microbiology , Escherichia coli/classification , Case-Control Studies , Diarrhea, Infantile/drug therapy , Drug Resistance, Microbial/genetics , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli Infections/drug therapy , Female , Humans , Infant , Male , Peru , Phylogeny , Time Factors , Virulence/geneticsABSTRACT
BACKGROUND: Diarrhoeal diseases cause illness and death among children younger than 5 years in low-income countries. We designed the Global Enteric Multicenter Study (GEMS) to identify the aetiology and population-based burden of paediatric diarrhoeal disease in sub-Saharan Africa and south Asia. METHODS: The GEMS is a 3-year, prospective, age-stratified, matched case-control study of moderate-to-severe diarrhoea in children aged 0-59 months residing in censused populations at four sites in Africa and three in Asia. We recruited children with moderate-to-severe diarrhoea seeking care at health centres along with one to three randomly selected matched community control children without diarrhoea. From patients with moderate-to-severe diarrhoea and controls, we obtained clinical and epidemiological data, anthropometric measurements, and a faecal sample to identify enteropathogens at enrolment; one follow-up home visit was made about 60 days later to ascertain vital status, clinical outcome, and interval growth. FINDINGS: We enrolled 9439 children with moderate-to-severe diarrhoea and 13,129 control children without diarrhoea. By analysing adjusted population attributable fractions, most attributable cases of moderate-to-severe diarrhoea were due to four pathogens: rotavirus, Cryptosporidium, enterotoxigenic Escherichia coli producing heat-stable toxin (ST-ETEC; with or without co-expression of heat-labile enterotoxin), and Shigella. Other pathogens were important in selected sites (eg, Aeromonas, Vibrio cholerae O1, Campylobacter jejuni). Odds of dying during follow-up were 8·5-fold higher in patients with moderate-to-severe diarrhoea than in controls (odd ratio 8·5, 95% CI 5·8-12·5, p<0·0001); most deaths (167 [87·9%]) occurred during the first 2 years of life. Pathogens associated with increased risk of case death were ST-ETEC (hazard ratio [HR] 1·9; 0·99-3·5) and typical enteropathogenic E coli (HR 2·6; 1·6-4·1) in infants aged 0-11 months, and Cryptosporidium (HR 2·3; 1·3-4·3) in toddlers aged 12-23 months. INTERPRETATION: Interventions targeting five pathogens (rotavirus, Shigella, ST-ETEC, Cryptosporidium, typical enteropathogenic E coli) can substantially reduce the burden of moderate-to-severe diarrhoea. New methods and accelerated implementation of existing interventions (rotavirus vaccine and zinc) are needed to prevent disease and improve outcomes. FUNDING: The Bill & Melinda Gates Foundation.
Subject(s)
Bacterial Infections/mortality , Diarrhea/microbiology , Diarrhea/mortality , Rotavirus Infections/mortality , Africa South of the Sahara , Asia, Western/epidemiology , Case-Control Studies , Child, Preschool , Cost of Illness , Developing Countries , Diarrhea, Infantile/microbiology , Diarrhea, Infantile/mortality , Female , Humans , Infant , Male , Prospective StudiesABSTRACT
A total of 220 enteroadherent Escherichia coli were identified from 729 Egyptian children with diarrhea using the HEp-2 adherence assay. Enteropathogenic E.coli (EPEC = 38) was common among children <6 months old and provoked vomiting, while diffuse-adhering E.coli (DAEC = 109) induced diarrheal episodes of short duration, and enteroaggregative E.coli (EAEC = 73) induced mild non-persistent diarrhea. These results suggest that EPEC is associated with infantile diarrhea in Egyptian children.
Subject(s)
Diarrhea, Infantile/epidemiology , Diarrhea, Infantile/microbiology , Enteropathogenic Escherichia coli/isolation & purification , Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Escherichia coli/classification , Child , Child, Preschool , Diarrhea, Infantile/diagnosis , Egypt/epidemiology , Enteropathogenic Escherichia coli/genetics , Enzyme-Linked Immunosorbent Assay , Escherichia coli/isolation & purification , Escherichia coli Infections/diagnosis , Feces/microbiology , Female , Humans , Infant , Male , Phenotype , PrevalenceABSTRACT
BACKGROUND: Diarrhea causes enormous morbidity and mortality in developing countries, yet the relative importance of multiple potential enteropathogens has been difficult to ascertain. METHODS: We performed a longitudinal cohort study from birth to 1 year of age in 147 infants in Dhaka, Bangladesh. Using multiplex polymerase chain reaction, we analyzed 420 episodes of diarrhea and 1385 monthly surveillance stool specimens for 32 enteropathogen gene targets. For each infant we examined enteropathogen quantities over time to ascribe each positive target as a probable or less-likely contributor to diarrhea. RESULTS: Multiple enteropathogens were detected by the first month of life. Diarrhea was associated with a state of overall pathogen excess (mean number of enteropathogen gene targets (± SE), 5.6 ± 0.1 vs 4.3 ± 0.1 in surveillance stool specimens; P < .05). After a longitudinal, quantitative approach was applied to filter out less-likely contributors, each diarrheal episode still had an average of 3.3 probable or dominant targets. Enteroaggregative Escherichia coli, Campylobacter, enteropathogenic E. coli, rotavirus, and Entamoeba histolytica were the most frequent probable contributors to diarrhea. Rotavirus was enriched in moderate to severe diarrheal episodes. CONCLUSIONS: In this community-based study diarrhea seemed to be a multipathogen event and a state of enteropathogen excess above a high carriage baseline.
Subject(s)
Campylobacter Infections/complications , Diarrhea, Infantile/etiology , Entamoebiasis/complications , Escherichia coli Infections/complications , Rotavirus Infections/complications , Bangladesh/epidemiology , Campylobacter/genetics , Campylobacter/isolation & purification , Campylobacter Infections/microbiology , Cohort Studies , Developing Countries , Diarrhea, Infantile/epidemiology , Diarrhea, Infantile/microbiology , Diarrhea, Infantile/parasitology , Entamoeba histolytica/genetics , Entamoeba histolytica/isolation & purification , Entamoebiasis/microbiology , Enteropathogenic Escherichia coli/genetics , Enteropathogenic Escherichia coli/isolation & purification , Escherichia coli/genetics , Escherichia coli/isolation & purification , Escherichia coli Infections/microbiology , Feces/microbiology , Feces/parasitology , Female , Humans , Infant , Infant, Newborn , Longitudinal Studies , Male , Multiplex Polymerase Chain Reaction , Rotavirus/genetics , Rotavirus/isolation & purification , Rotavirus Infections/virologyABSTRACT
BACKGROUND: Serious bacterial infections are a major cause of death in early infancy in developing countries. Inexpensive and accessible interventions that can add to the effect of standard antibiotic treatment could reduce infant mortality. We measured the effect of zinc as an adjunct to antibiotics in infants with probable serious bacterial infection. METHODS: In this randomised, double-blind, placebo-controlled trial, we enrolled infants aged 7-120 days with probable serious bacterial infection at three hospitals in New Delhi, India, between July 6, 2005, and Dec 3, 2008. With computer-generated sequences, we randomly assigned infants in permuted blocks of six, stratified by whether patients were underweight or had diarrhoea at enrolment, to receive either 10 mg of zinc or placebo orally every day in addition to standard antibiotic treatment. The primary outcome was treatment failure, which was defined as a need to change antibiotics within 7 days of randomisation, or a need for intensive care, or death at any time within 21 days. Participants and investigators were masked to treatment allocation. All analyses were done by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00347386. FINDINGS: 352 infants were randomly assigned to receive zinc and 348 to placebo. 332 given zinc and 323 given placebo could be assessed for treatment failure. Significantly fewer treatment failures occurred in the zinc group (34 [10%]) than in the placebo group (55 [17%]; relative risk reduction 40%, 95% CI 10-60, p=0·0113; absolute risk reduction 6·8%, 1·5-12·0, p=0·0111). Treatment of 15 (95% CI eight to 67) infants with zinc would prevent one treatment failure. Ten infants receiving zinc died compared with 17 given placebo (relative risk 0·57, 0·27-1·23, p=0·15). INTERPRETATION: Zinc could be given as adjunct treatment to reduce the risk of treatment failure in infants aged 7-120 days with probable serious bacterial infection. FUNDING: Department of Biotechnology, Government of India; the European Commission; the Meltzer Foundation; and the Research Council of Norway.
Subject(s)
Bacterial Infections/drug therapy , Zinc/therapeutic use , Administration, Oral , Anti-Bacterial Agents/therapeutic use , Bacterial Infections/complications , Bacterial Infections/diagnosis , Body Weight , Diarrhea, Infantile/drug therapy , Diarrhea, Infantile/microbiology , Double-Blind Method , Drug Therapy, Combination , Female , Humans , Infant , Infant, Newborn , Male , Trace Elements/administration & dosage , Trace Elements/therapeutic use , Treatment Failure , Weight Gain/drug effects , Zinc/administration & dosageABSTRACT
AIM: The aim of this work has been a presentation of causes of acute infectious diarrhea. MATERIAL AND METHODOLOGY: The examinees have been the infants treated at the Pediatric Clinic. The diagnosis has been established on the basis ofanamnesis, physical examination and feces examination on bacteria, viruses, protozoa and fungi. RESULTS: During the period of seven years a number of patients that suffered from acute infectious diarrhea was 1050 (31.82%) out of a total number (3300) with diarrhea. The bacteriological examination proved positive on majority of them or in 655 (62.38%) cases, the viral examination proved positive in 375 (35.72%) cases, whereas fungi examination proved positive in only 3 cases (0.28%). The most frequent bacteria have been Salmonellae species in 255 (38.93%) cases and E. coli in 142 (21.69%) cases, the less frequent have been Yersinia enterocolitica in 16 (2.44%) cases and Bacillus cereus in 4 (0.61%) cases. The most frequent serotypes of Salmonella have been S. Wien in 92 (36.07%) and S. Gloucester in 42 (16.47%) cases. Enteropathogenic E. Coli (most frequent serotypes O111 and O55) has been found in 112 (78.88%) cases. From the group of Shigella the most frequent has been Sh. Flexneri (most frequent serotypes 6 and 4) in 35 (58.33%) cases. The same feces sample of the majority of examinees 501 (76.48%) cases contained only one bacteria (single bacteria), two bacteria (associated bacteria) have been found in 102 (15.17%) cases, three types of bacteria have been found in 17 (2.59%) cases. Rotavirus has been isolated in 271 (72.26%) cases in comparison to adenoviruses that have been isolated in 65 (17.33%) cases. Rotavirus and adenoviruses have been isolated in 39 (10.40%) cases. CONCLUSION: Infectious acute diarrhea appears frequently, and as causes of it usually appear to be pathogenic bacteria in comparison to viruses, protozoa and fungi.
Subject(s)
Diarrhea, Infantile/microbiology , Acute Disease , Humans , InfantABSTRACT
The overall aim of the Global Enteric Multicenter Study-1 (GEMS-1) is to identify the etiologic agents associated with moderate-to-severe diarrhea (MSD) among children <5 years of age, and thereby the attributable pathogen-specific population-based incidence of MSD, to guide investments in research and public health interventions against diarrheal disease. To accomplish this, 9 core assumptions were vetted through widespread consultation: (1) a limited number of etiologic agents may be responsible for most MSD; (2) a definition of MSD can be crafted that encompasses cases that might otherwise be fatal in the community without treatment; (3) MSD seen at sentinel centers is a proxy for fatal diarrheal disease in the community; (4) matched case/control is the appropriate epidemiologic design; (5) methods across the sites can be standardized and rigorous quality control maintained; (6) a single 60-day postenrollment visit to case and control households creates mini-cohorts, allowing comparisons; (7) broad support for GEMS-1 messages can be achieved by incorporating advice from public health spokespersons; (8) results will facilitate the setting of investment and intervention priorities; and (9) wide acceptance and dissemination of the GEMS-1 results can be achieved.
Subject(s)
Diarrhea, Infantile/epidemiology , Diarrhea/epidemiology , Epidemiologic Research Design , Multicenter Studies as Topic/methods , Case-Control Studies , Child, Preschool , Clinical Laboratory Techniques , Diarrhea/diagnosis , Diarrhea/microbiology , Diarrhea, Infantile/diagnosis , Diarrhea, Infantile/microbiology , Global Health , Hospitals , Humans , Infant , Sentinel SurveillanceABSTRACT
Four Cryptosporidium spp. and 6 C. hominis subtypes were isolated from 102 of 6,284 patients in 3 pediatric hospitals in People's Republic of China. A cryptosporidiosis outbreak was identified retrospectively. The outbreak lasted >1 year and affected 51.4% of patients in 1 hospital ward, where 2 C. hominis subtypes with different virulence were found.