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1.
Curr Microbiol ; 79(6): 182, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35508821

RESUMO

Escherichia coli (E. coli) is an important pathogen that causes diarrhea and death in piglets. In this work, whole genome sequencing of two E. coli strains (ZB-1, ZWW-1) isolated from Saba pigs. And focus on the relationship between drug resistance, pathogenic phenotype and genotype of the two strains. This study analyzed the drug susceptibility of the two strains. The LD50 values, tissue bacterial load and intestinal pathological changes in mice infected with the two strains. The differences in gene functions such as drug resistance, virulence, and unique genes between the two strains, as well as the genetic evolutionary relationship of housekeeping genes were analyzed. The results showed that the two strains had the same resistance phenotype to most drugs. The LD50 value, tissue load, and pathological changes in mice infected with strain ZB-1 revealed that this strain was more virulent and pathogenic than strain ZWW-1. In addition, the housekeeping genes contained in the two strains are in the same large branch as E. coli of different species, and the genetic evolution is stable. All of them carry EPEC-type strain-specific virulence genes escV and ent, indicating that they are all new members of EPEC-type strains. This study laid the foundation for understanding the genetic background and biological characteristics of E. coli from Saba pigs.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Diarreia/microbiologia , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Camundongos , Filogenia , Suínos , Virulência/genética , Sequenciamento Completo do Genoma
2.
Sci Rep ; 12(1): 7210, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35505092

RESUMO

Lactiplantibacillus plantarum (strains 22F and 25F) and Pediococcus acidilactici (strain 72N) have displayed antibacterial activity in vitro, suggesting that they could be used to support intestinal health in pigs. The aim of this study was to determine if microencapsulated probiotics could reduce the severity of infection with enterotoxigenic Escherichia coli (ETEC) in weaned pigs. Sixty healthy neonatal piglets were cross-fostered and separated into five groups. Piglets to be given the microencapsulated probiotics received these orally on days 0, 3, 6, 9, and 12. Only piglets in groups 1 and 5 did not receive probiotics: those in groups 2 and 4 received the three microencapsulated probiotic strains (multi-strain probiotic), and piglets in group 3 received microencapsulated P. acidilactici strain 72N. After weaning, the pigs in groups 3-5 were challenged with 5 mL (at 109 CFU/mL) of pathogenic ETEC strain L3.2 carrying the k88, staP, and stb virulence genes. The multi-strain probiotic enhanced the average daily gain (ADG) and feed conversion ratio (FCR) of weaned piglets after the ETEC challenge (group 4), whilst supplementing with the single-strain probiotic increased FCR (group 3). Piglets in groups 3 and 4 developed mild to moderate diarrhoea and fever. In the probiotic-fed piglets there was an increase in lactic acid bacteria count and a decrease in E. coli count in the faeces. By using real-time PCR, virulence genes were detected at lower levels in the faeces of pigs that had received the probiotic strains. Using the MILLIPLEX MAP assay, probiotic supplementation was shown to reduce pro-inflammatory cytokines (IL-1α, IL-6, IL-8, and TNFα), while group 4 had high levels of anti-inflammatory cytokine (IL-10). Challenged piglets receiving probiotics had milder intestinal lesions with better morphology, including greater villous heights and villous height per crypt depth ratios, than pigs just receiving ETEC. In conclusion, prophylactic administration of microencapsulated probiotic strains may improve outcomes in weaned pigs with colibacillosis.


Assuntos
Escherichia coli Enterotoxigênica , Pediococcus acidilactici , Probióticos , Doenças dos Suínos , Animais , Diarreia/microbiologia , Probióticos/farmacologia , Probióticos/uso terapêutico , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/prevenção & controle
3.
J Med Microbiol ; 71(4)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35476821

RESUMO

Introduction . Acute diarrhoea can be caused by Salmonella species, Shigella species, Yersinia enterocolitica, Campylobacter species and Plesiomonas shigelloides (SSYCP). In clinical practice, however, polymerase chain reaction (PCR) for SSYCP is frequently performed as part of the diagnostic work-up for patients with chronic diarrhoea and gastrointestinal complaints.Hypothesis. This study postulates that PCR for SSYCP is of limited clinical use in patients with chronic diarrhoea and gastrointestinal complaints.Aim. The primary aim of this study is to evaluate whether testing for SSYCP remains sensible in patients with chronic diarrhoea and gastrointestinal symptoms and if earlier testing leads to more positive PCR results.Methodology. Between January 2017 and December 2018, data on PCR results, culture results, symptoms, symptom to testing interval (STI) and immune status were retrospectively collected from the medical records of patients with gastrointestinal symptoms for whom PCR results for SSYCP were available. The STIs of PCR-positive patients and PCR-negative patients were compared.Results. In total, 146 PCR-positive and 149 PCR-negative patients were included. STIs of <7 days occurred in 55 % of all PCR-positive patients compared to 38 % in PCR-negative patients. PCR-positive patients were more often tested within 7 days after onset of gastrointestinal symptoms or diarrhoea. A third of PCR-positive patients had an STI of >7 days. Immunocompromised patients had a shorter STI. Admitted patients had a shorter STI. Eighty-six PCR-positive patients had a positive culture (58 %). Antibiotic use 3 months prior to PCR testing was correlated with negative PCR results.Conclusions . This study shows that early testing correlates with more positive PCR results and underlines that PCR for SSYCP is of lesser importance in the diagnostic workup of chronic diarrhoea and/or gastrointestinal symptoms. The shorter STI found in immunocompromised patients is possibly due to a lower threshold for testing in this population. It is also important to take recent antibiotic use into consideration when interpreting PCR results, given the correlation between negative PCR results and antibiotic use. Careful and precise documentation of symptoms in medical records is essential for clinical practice and research.


Assuntos
Diarreia , Doenças Sexualmente Transmissíveis , Antibacterianos , Bactérias/genética , Diarreia/diagnóstico , Diarreia/microbiologia , Fezes/microbiologia , Humanos , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Doenças Sexualmente Transmissíveis/diagnóstico
4.
Arch Microbiol ; 204(5): 257, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35416536

RESUMO

In recent years, 16S ribosomal DNA (16S rDNA) sequencing has been widely developed. In the present study, we investigated the changes of fecal flora analyzed by sequencing of 16S rDNA and the alteration of blood biochemical indexes in cats during diarrhea. Seven normal fecal samples and seven fecal samples of British Shorthair cats with bacterial diarrhea about 6 months old were collected. The 16S rDNA V3 region of the bacteria was amplified for high-throughput sequencing. Finally, species analysis at various levels was performed. At the same time, samples of blood were taken to examine the changes of biochemical indexes in cats with diarrhea. The abundance and diversity of microflora in the healthy group were greater than those in the diarrhea group. The normal floras in the feces of healthy cats were Firmicutes, Actinobacteria, Bacteroidetes and Proteobacteria. The content of Proteobacteria and Firmicutes varied greatly in diarrheal cats. In addition, the number of white blood cells, lymphocytes, neutrophils, and globulin were increased in cats with diarrhea, whereas albumin level was decreased in diarrheal cats. In conclusion, the present study suggests 16SrDNA technology showed that the intestinal Proteus was abundant, and the content of Firmicutes was scarce in cats with diarrhea. Escherichia-Shigella was the main pathogens in this sample. Rapid blood biochemical tests may help clinicians to assess the severity and prognosis of cats with diarrhea.


Assuntos
Bactérias , Diarreia , Animais , Bactérias/genética , Gatos , DNA Ribossômico/genética , Diarreia/microbiologia , Diarreia/veterinária , Fezes/microbiologia , Firmicutes/genética , Proteobactérias/genética , RNA Ribossômico 16S/genética
5.
Oxid Med Cell Longev ; 2022: 3355687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401925

RESUMO

Since the human and porcine digestive systems have similar anatomical structures and physiological functions, pigs are a useful animal model for studying human digestive diseases. By investigating intestinal metabolites in piglets after weaning, this study attempted to identify the inherent connection between dietary protein levels and changes in the intestinal microbiota of piglets. Casein was employed as the only source of protein for the piglets in this study to avoid the influence of other protein sources. 14 weaning at 28-day-old piglets (6.9 ± 0.19 kg) formed into two dietary groups: 17% casein fed group (LP) and 30% casein fed group (HP). Piglets were allowed to free food and water during the 2-week experiment. Throughout the trial, the piglets' diarrhea index (1: no diarrhea and 3: watery diarrhea) and food intake were noted during the experiment. We discovered piglets fed a high-protein diet developed diarrhea throughout the duration of the research, whereas piglets fed a normal protein diet did not. In addition, the HP group had lower feed intake and body weight than the control group (P < 0.05). The HP diet influenced the content of short-chain and branched-chain fatty acids in the colon, including acetate and isovaleric acid. The ileal microbiota's 16S rRNA gene was sequenced, and it was discovered that the relative abundance of gastrointestinal bacteria differed between the HP and control groups. Dietary protein levels influenced bile acid biosynthesis, alpha-linolenic acid metabolism, phospholipid biosynthesis, arachidonic acid metabolism, fatty acid biosynthesis, retinol metabolism, arginine and proline metabolism, pyrimidine metabolism, tryptophan metabolism, and glycine and serine metabolism, according to gas chromatography-mass spectrometry analysis. Furthermore, a correlation analysis of the pooled information revealed a possible link between intestinal metabolites and specific bacteria species. These findings demonstrate that weaned piglets' microbiota composition and metabolites are modified by a high-protein diet and thus inducing severe postweaning diarrhea and inhibiting growth performance. However, the potential molecular mechanism of this regulation in the growth of piglets remains unclear.


Assuntos
Ração Animal , Caseínas , Ração Animal/análise , Animais , Diarreia/microbiologia , Diarreia/veterinária , Dieta , Proteínas na Dieta , Suplementos Nutricionais/análise , RNA Ribossômico 16S , Suínos , Desmame
6.
Vet Microbiol ; 269: 109421, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35429815

RESUMO

Brachyspira (B.) pilosicoli is a bacterium causing porcine intestinal spirochaetosis, a disease characterized by diarrhoea and depressed growth rates especially in nursery and fattening pigs. Knowledge of the epidemiology and antimicrobial susceptibility of this pathogen is limited. Therefore, the aim of this study was to analyse the distribution, genetic heterogeneity, and antimicrobial susceptibility of B. pilosicoli field isolates from Swiss pig farms. Faecal swabs of 693 animals originating from 156 herds were analysed for the presence of Brachyspira spp. using culture and polymerase chain reaction identification. Further characterisation was performed using multilocus sequence typing (MLST) and broth dilution antimicrobial susceptibility testing. With 52.6% positive herds, B. pilosicoli could be frequently isolated from herds with animals suffering from diarrhoea. In herds with animals without clinical signs of diarrhoea, detection was significantly less frequent with only 10.5% positive herds (p 0.001). Among 80 isolates used for typing, genetic heterogeneity was observed with 44 different sequence types (ST) which often differed from herd to herd. No predominant ST was observed. More than 73.0% of the 41 B. pilosicoli isolates analysed, showed minimal inhibitory concentration values above the wild type cut-off values for lincomycin, tylvalosin and/ or tylosin. For tiamulin, valnemulin and doxycycline, this was the case in 48.8%, 43.9% and 36.6%, respectively. In conclusion, a diverse population of B. pilosicoli exhibited decreased susceptibility to antimicrobials used against Brachyspira infections. Monitoring of resistance in Brachyspira spp. is highly recommended to support targeted use of antimicrobials in pigs.


Assuntos
Brachyspira , Infecções por Bactérias Gram-Negativas , Doenças dos Suínos , Animais , Antibacterianos/farmacologia , Diarreia/epidemiologia , Diarreia/microbiologia , Diarreia/veterinária , Heterogeneidade Genética , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/veterinária , Tipagem de Sequências Multilocus/veterinária , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia
8.
Front Cell Infect Microbiol ; 12: 805481, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402298

RESUMO

Short-chain fatty acids (SCFA) are principal nutrient substrates of intestinal epithelial cells that regulate the epithelial barrier in yaks. Until now, metagenomics sequencing has not been reported in diarrheal yaks. Scarce information is available regarding the levels of fecal SCFA and diarrhea in yaks. So, our study aims to identify the potential pathogens that cause the emerging diarrhea and explore the potential relationship of short-chain fatty acids in this issue. We estimated diarrhea rate in yaks after collecting an equal number of fecal samples from affected animals. Metagenomics sequencing and quantitative analysis of SCFA were performed, which revealed 15%-25% and 5%-10% prevalence of diarrhea in yak's calves and adults, respectively. Violin box plot also showed a higher degree of dispersion in gene abundance distribution of diarrheal yaks, as compared to normal yaks. We found 366,163 significant differential abundance genes in diarrheal yaks, with 141,305 upregulated and 224,858 downregulated genes compared with normal yaks via DESeq analysis. Metagenomics binning analysis indicated the higher significance of bin 33 (Bacteroidales) (p < 0.05) in diarrheal animals, while bin 10 (p < 0.0001), bin 30 (Clostridiales) (p < 0.05), bin 51 (Lactobacillales) (p < 0.05), bin 8 (Lachnospiraceae) (p < 0.05), and bin 47 (Bacteria) (p < 0.05) were significantly higher in normal yaks. At different levels, a significant difference in phylum (n = 4), class (n = 8), oder (n = 8), family (n = 16), genus (n = 17), and species (n = 30) was noticed, respectively. Compared with healthy yaks, acetic acid (p < 0.01), propionic acid (p < 0.01), butyric acid (p < 0.01), isobutyric acid (p < 0.01), isovaleric acid (p < 0.05), and caproic acid (p < 0.01) were all observed significantly at a lower rate in diarrheal yaks. In conclusion, besides the increased Staphylococcus aureus, Babesia ovata, Anaplasma phagocytophilum, Bacteroides fluxus, viruses, Klebsiella pneumonia, and inflammation-related bacteria, the decrease of SCFA caused by the imbalance of intestinal microbiota was potentially observed in diarrheal yaks.


Assuntos
Microbioma Gastrointestinal , Metagenômica , Animais , Bactérias/genética , Bovinos , Clostridiales , Diarreia/microbiologia , Ácidos Graxos Voláteis , Fezes
9.
Front Cell Infect Microbiol ; 12: 842007, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372106

RESUMO

In the last 20 years, accumulating evidence indicates that the gut microbiota contribute to the development, maturation, and regulation of the host immune system and mediate host anti-pathogen defenses. Lactobacillus casei (L.casei) is a normal flora of the gastrointestinal tract in mammals and, as a great mucosal delivery vehicle, has wide use in bioengineering. However, the diarrhea prevention role of commensal intestinal microbiota interfered by the recombinant L.casei (rL.casei) in newborn piglets is not well understood. In our study, newborn piglets orally fed with the rL.casei surface displayed the fimbrial protein K88 of enterotoxigenic Escherichia coli (ETEC) and their feces were collected for a period of time after feeding. The next-generation sequencing of these fecal samples showed that the relative abundance of L.casei was significantly increased. The oral administration of rL.casei altered the intestinal microbial community as evidenced by altered microbial diversity and microbial taxonomic composition. Remarkably, the functional enhancing of the intestinal bacterial community by rL.casei was positively correlated with membrane transport, replication, and repair (p < 0.05). The specific antibody detection indicates that high levels of anti-K88 secretory immunoglobulin A (sIgA) were induced in fecal samples and systemic immunoglobulin G was produced in serum. The diarrhea rate in piglets caused by ETEC K88 was decreased by about 24%. Thus, the oral administration of rL.casei not only activated the mucosal and humoral immune responses in vivo but also contributed to shape the intestinal probiotics in newborn piglets and to significantly reduce the diarrhea rates of newborn piglets.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Microbioma Gastrointestinal , Lactobacillus casei , Animais , Animais Recém-Nascidos , Diarreia/microbiologia , Diarreia/prevenção & controle , Diarreia/veterinária , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Mamíferos , Suínos
10.
Epidemiol Infect ; 150: e52, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35241189

RESUMO

Shiga toxin-producing Escherichia coli (STEC) serogroup O157 is a zoonotic, foodborne gastrointestinal pathogen of major public health concern. We describe the epidemiology of STEC O157 infection in England by exploring the microbiological and clinical characteristics, the demographic and geographical distribution of cases, and examining changes in environmental exposures over 11 years of enhanced surveillance. Enhanced surveillance data including microbiological subtyping, clinical presentations and exposures were extracted for all cases resident in England with evidence of STEC O157 infection, either due to faecal culture or serology detection. Incidence rates were calculated based on mid-year population estimates from the Office of National Statistics (ONS). Demographics, geography, severity and environmental exposures were compared across the time periods 2009-2014 and 2015-2019. The number of cases reported to national surveillance decreased, with the mean cases per year dropping from 887 for the period 2009-2014 to 595 for the period 2015-2019. The decline in STEC O157 infections appears to be mirrored by the decrease in cases infected with phage type 21/28. Although the percentage of cases that developed HUS decreased, the percentage of cases reporting bloody diarrhoea and hospitalisation remained stable. The number of outbreaks declined over time, although more refined typing methods linked more cases to each outbreak. Integration of epidemiological data with microbiological typing data is essential to understanding the changes in the burden of STEC infection, assessment of the risks to public health, and the prediction and mitigation of emerging threats.


Assuntos
Infecções por Escherichia coli , Escherichia coli O157 , Escherichia coli Shiga Toxigênica , Diarreia/epidemiologia , Diarreia/microbiologia , Infecções por Escherichia coli/microbiologia , Humanos , Sorogrupo
11.
PLoS One ; 17(3): e0262199, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35255081

RESUMO

Post-weaning diarrhea (PWD) in pigs has mainly an infectious basis and control strategies are centred on antibiotics added to the diet. Given concerns on the spread of multi-resistant bacteria, it is necessary to develop alternative prophylactic approaches to control PWD in piglets. The most promising alternative strategies are based on substances that act indirectly on the bacteria by stimulating the immune system or by improving gut health. The aim of this study was to evaluate the effect on the gut microbiota of feed supplemented with a mixture of essential oils (garlic and oregano) in weaning piglets, compared to traditional PWD management (in-feed antibiotics) and to a control group without any diet supplementation. The study involved 197 piglets from 18 litters in a single farm. The piglets were followed from birth to day 58 of age and were weaned at day 26. During the experimental period, the animals were monitored for weight and growth, average daily gain, morbidity and mortality. For the metataxonomics analysis, rectal samples were collected from 17 piglets from the three experimental groups at 4 different time-points (days 1, 12, 26 and 58). Results revealed that the gut microbiota in pre- and post-weaning piglets was dominated by the phyla Firmicutes (51%), Bacteroidetes (25%) and Proteobacteria (16%), which together make up for over 90% of the entire piglet core gut microbiota. The core microbiota comprised 10 taxa before weaning and 43 taxa after weaning, with 7 taxa overlapping between timepoints: two of them (Prevotella 9, p-value = 0.00095; Solobacterium p-value = 0.00821) were significantly more abundant after weaning. All alpha diversity indexes were significantly different between pre- and post-weaning, while only Shannon and Simpson diversity and equitability were significantly different between treatments. Based on the matrix of Bray-Curtis dissimilarities, samples showed clear clustering per timepoint (before and after weaning, p-value < 0.001) and between treatments by timepoint (p-value = 0.0086). The oil-diet group showed a consistently higher F:B ratio at all timepoints. These results show that the pig gut microbiota changes significantly with weaning, and suggest that the use of essential oils as feed supplementation to control PWD does not seem to alter sgnificantly the microbiota nor the growth parameters of piglets, however modifications of specific taxa may occur.


Assuntos
Microbioma Gastrointestinal , Óleos Voláteis , Ração Animal/análise , Animais , Antibacterianos/farmacologia , Bactérias/genética , Diarreia/microbiologia , Diarreia/prevenção & controle , Diarreia/veterinária , Firmicutes , Suínos , Desmame
12.
Travel Med Infect Dis ; 47: 102293, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35247581

RESUMO

Travellers' diarrhoea (TD) is the most frequent illness experienced by international travellers to lower-income countries with bacterial agents considered to account for 80-90% of cases. In this review, we summarise evidence published on bacterial TD over the past 10 years, focusing on the epidemiology and aetiology of TD. Diarrhoeagenic Escherichia coli (DEC) continue to be the most commonly implicated bacteria in TD, although Enteropathogenic E. coli (EPEC) and Enteroaggregative E. coli (EAEC) now appear to be predominant where Enterotoxigenic E. coli (ETEC) was previously considered most prevalent globally. Where fluroquinolone resistance had primarily been documented for Campylobacter in Southeast Asia, widespread resistance has been observed in most regions of the world for multiple enteropathogens, including Shigella, Salmonella, ETEC and EAEC. Implementation of novel molecular methods for pathogen detection has led to identification of bacterial pathogens, including Clostridium difficile (with and without the use of prior antibiotics), Arcobacter species and Bacteroides fragilis, as aetiological agents in TD. The widespread resistance to first-line antibiotics in multiple bacterial enteropathogens warrants continued surveillance and re-evaluation of current treatment practices. Further investigations are required to determine the prevalence and geographical distribution of bacterial enteropathogens that have been more recently implicated in TD.


Assuntos
Infecções Bacterianas , Escherichia coli Enterotoxigênica , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Fezes/microbiologia , Humanos , Viagem
13.
Vet Clin North Am Food Anim Pract ; 38(1): 107-119, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35219479

RESUMO

Although diarrhea in dairy calves is common, it is not always due to bacteria. Escherichia coli, Salmonella, and Clostridium perfringens are the most commonly implicated bacteria, but an etiologic diagnosis should be sought before specific treatment is instituted. Nonspecific treatment such as fluid, electrolyte, and nutritional support should be accomplished while diagnostics are pending. Antimicrobials should not be a first-line therapy for calf diarrhea. Control measures are discussed.


Assuntos
Doenças dos Bovinos , Infecções por Escherichia coli , Enteropatias , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Diarreia/microbiologia , Diarreia/veterinária , Escherichia coli , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Fezes/microbiologia , Enteropatias/veterinária
14.
Foodborne Pathog Dis ; 19(4): 241-247, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35138934

RESUMO

In December 2019, four children of the same school were hospitalized due to severe diarrhea, vomiting, and fever, and the mother of one child was diagnosed with hemolytic uremic syndrome (HUS). Escherichia coli O157 NM was isolated from the stool of one child, whereas Campylobacter jejuni isolates were found in feces, raw foods, environmental samples, and tap water. In addition, the same pulsed-field gel electrophoresis profile was identified in C. jejuni isolated from feces and tap water. One child died of renal failure and another due to respiratory failure. Based on symptoms and bacterial isolation, the deaths were assigned to E. coli O157 NM, but coinfection with C. jejuni may have contributed to the severity of symptoms. These were the first deaths assigned to E. coli O157 NM registered in Brazil.


Assuntos
Campylobacter jejuni , Infecções por Escherichia coli , Escherichia coli O157 , Brasil/epidemiologia , Campylobacter , Criança , Diarreia/microbiologia , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Humanos , Masculino , Água
15.
Curr Opin Pediatr ; 34(2): 147-155, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35165210

RESUMO

PURPOSE OF REVIEW: This review describes recent findings about the burden of bacterial diarrhoea and its potential complications, newer diagnostics, the emerging threat of multidrug resistance, and the promise of vaccines in development. RECENT FINDINGS: Introduction of rotavirus vaccines in over 110 countries has changed the landscape of diarrheal pathogens. In upper middle and high-income countries, the incidence of rotavirus-specific and all-cause gastroenteritis has declined substantially, and norovirus has become the major pathogen in many settings. Bacterial pathogens cause approximately 10-15% of episodes, most often Shigella, nontyphoidal Salmonella (NTS) Campylobacter and Shiga toxin-producing Escherichia coli (STEC). In lower income countries, bacterial pathogens remain a major cause of medically attended diarrhoea with Shigella, Campylobacter and enterotoxigenic Escherichia coli (ETEC) predominating. Multidrug-resistant strains of Shigella, NTS and, Campylobacter have emerged globally requiring judicious use of antibiotics according to current guidance. SUMMARY: Management of bacterial diarrhoea includes standard fluid and electrolyte therapy, vigilance for potential complications, and use of antibiotics for children who have moderate-severe illness due to pathogens for which efficacy has been demonstrated, or for those at high risk for severe disease. The threat of multiply resistant strains provides impetus for preventive strategies such as development of vaccines.


Assuntos
Infecções Bacterianas , Escherichia coli Enterotoxigênica , Gastroenterite , Antibacterianos/uso terapêutico , Infecções Bacterianas/complicações , Criança , Diarreia/epidemiologia , Diarreia/microbiologia , Humanos
16.
Microbiome ; 10(1): 29, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35139923

RESUMO

BACKGROUND: Chronic diarrhea is a common disease causing morbidity and mortality of captive rhesus macaques (RMs, Macaca mulatta). Chronic diarrhea in RMs is typically characterized by long-term diarrhea and a weak response to antibiotic treatment. Diarrhea is also a common disease in humans and can cause death. However, the etiology of about half of diarrheal cases of humans is still unclear. Therefore, we performed shotgun metagenomic sequencing to characterize the differences in the gut microbiome and resistome of chronic diarrhea RMs and asymptomatic individuals. RESULTS: Our results showed Lactobacillus spp. (mainly L. johnsonii, L. reuteri and L. amylovorus) were significantly depleted in chronic diarrhea RM guts compared to asymptomatic individuals (5.2 vs 42.4%). Functional annotation of genes suggested these Lactobacillus spp. carried genes involved in the adhesion of intestinal epithelial cells and production of bacteriocin. Chronic diarrhea RM guts also had a significantly greater abundance of many other gut bacteria, including mucin-degrading bacteria and opportunistic pathogens. The metabolic pathways of chronic diarrhea RM gut microbiome were enriched in aerobactin biosynthesis, while the metabolic pathways of asymptomatic RM gut microbiome were enriched in the production of short-chain fatty acids (SCFAs). Chronic diarrhea RM guts had a significantly greater abundance of antibiotic resistance genes (ARGs), such as ermF, aph(3')-IIIa, ermB, and floR. The strains isolated from feces and tissue fluid of chronic diarrhea RMs had higher resistance rates to the majority of tested antibiotics, but not cephamycin and carbapenem antibiotics. Gut microbial composition comparisons showed that several captive nonhuman primate (NHP) guts were more similar to the guts of humans with a non-westernized diet than humans with a westernized diet. Chronic diarrhea RM gut microbiome was strikingly similar to rural-living humans with diarrhea and humans with a non-westernized diet than asymptomatic RMs. CONCLUSIONS: Our results suggested chronic diarrhea significantly altered the composition and metabolic pathways of the RM gut microbiome. The frequent use of antibiotics caused antibiotic resistance in chronic diarrhea RM gut microbiome with serious consequences for individual treatment and survival. The findings of this study will help us to improve the effective prevention and treatment of diarrhea in RMs. Video Abstract.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Diarreia/veterinária , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Humanos , Macaca mulatta
17.
Microbiome ; 10(1): 31, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35184756

RESUMO

BACKGROUND: Establishing fecal microbiota transplantation (FMT) to prevent multifactorial diarrhea in calves is challenging because of the differences in farm management practices, the lack of optimal donors, and recipient selection. In this study, the underlying factors of successful and unsuccessful FMT treatment cases are elucidated, and the potential markers for predicting successful FMT are identified using fecal metagenomics via 16S rRNA gene sequencing, fecal metabolomics via capillary electrophoresis time-of-flight mass spectrometry, and machine learning approaches. RESULTS: Specifically, 20 FMT treatment cases, in which feces from healthy donors were intrarectally transferred into recipient diarrheal calves, were conducted with a success rate of 70%. Selenomonas was identified as a microorganism genus that showed significant donor-recipient compatibility in successful FMT treatments. A strong positive correlation between the microbiome and metabolome data, which is a prerequisite factor for FMT success, was confirmed by Procrustes analysis in successful FMT (r = 0.7439, P = 0.0001). Additionally, weighted gene correlation network analysis confirmed the positively or negatively correlated pairs of bacterial taxa (family Veillonellaceae) and metabolomic features (i.e., amino acids and short-chain fatty acids) responsible for FMT success. Further analysis aimed at establishing criteria for donor selection identified the genus Sporobacter as a potential biomarker in successful donor selection. Low levels of metabolites, such as glycerol 3-phosphate, dihydroxyacetone phosphate, and isoamylamine, in the donor or recipients prior to FMT, are predicted to facilitate FMT. CONCLUSIONS: Overall, we provide the first substantial evidence of the factors related to FMT success or failure; these findings could improve the design of future microbial therapeutics for treating diarrhea in calves. Video abstract.


Assuntos
Diarreia , Transplante de Microbiota Fecal , Animais , Bovinos , Diarreia/microbiologia , Diarreia/terapia , Transplante de Microbiota Fecal/métodos , Fezes/microbiologia , RNA Ribossômico 16S/genética , Resultado do Tratamento
18.
PLoS Negl Trop Dis ; 16(2): e0010177, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35139116

RESUMO

Enterotoxigenic Escherichia coli (ETEC) strains are a leading cause of children's and travelers' diarrhea. Developing effective vaccines against this heterologous group has proven difficult due to the varied nature of toxins and adhesins that determine their pathology. A multivalent candidate vaccine was developed using a multi-epitope fusion antigen (MEFA) vaccinology platform and shown to effectively elicit broad protective antibody responses in mice and pigs. However, direct protection against ETEC colonization of the small intestine was not measured in these systems. Colonization of ETEC strains is known to be a determining factor in disease outcomes and is adhesin-dependent. In this study, we developed a non-surgical rabbit colonization model to study immune protection against ETEC colonization in rabbits. We tested the ability for the MEFA-based vaccine adhesin antigen, in combination with dmLT adjuvant, to induce broad immune responses and to protect from ETEC colonization of the rabbit small intestine. Our results indicate that the candidate vaccine MEFA antigen elicits antibodies in rabbits that react to seven adhesins included in its construction and protects against colonization of a challenge strain that consistently colonized naïve rabbits.


Assuntos
Antígenos de Bactérias/administração & dosagem , Diarreia/prevenção & controle , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Escherichia coli Enterotoxigênica/imunologia , Epitopos/imunologia , Infecções por Escherichia coli/prevenção & controle , Vacinas contra Escherichia coli/administração & dosagem , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Diarreia/sangue , Diarreia/microbiologia , Modelos Animais de Doenças , Escherichia coli Enterotoxigênica/genética , Epitopos/genética , Infecções por Escherichia coli/sangue , Infecções por Escherichia coli/microbiologia , Vacinas contra Escherichia coli/genética , Vacinas contra Escherichia coli/imunologia , Humanos , Imunização , Intestino Delgado/imunologia , Intestino Delgado/microbiologia , Coelhos
19.
J Infect Dev Ctries ; 16(1): 147-156, 2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-35192532

RESUMO

INTRODUCTION: Diarrheagenic Escherichia coli pathotypes are important aetiological agents of diarrhoeal illness among children from less developed areas, worldwide. Diarrheagenic E. coli pathotypes strains are increasingly becoming drug resistant, thus effective and accessible therapeutic alternatives are required for their treatment; herbal extracts may be a potential alternative. AIMS: to evaluate Echeveria craigiana, E. kimnachii, and E. subrigida methanol extracts antibacterial effect on six diarrheagenic E. coli reference strains and on human colorectal adenocarcinoma cells viability and cytokine production. METHODOLOGY: Diarrheagenic E. coli pathotypes reference strains: typical enteropathogenic E2348/69, enterotoxigenic H10407, enterohaemorrhagic O157:H7/EDL933, enteroinvasive E11, diffusely adherent C18451-A, and enteroaggregative 042 E. coli. E craigiana, E. kimnachii, and E. subrigida leaves, collected at Sinaloa, Mexico, were freeze-dried and macerated in methanol solvent. Antibacterial activity was determined by a novel method developed in our laboratory, bacterial oxygen consumption by polarographic oxygen electrode technique and membrane integrity by two methods (live/dead and protein leakage assays). Colorectal adenocarcinoma cells viability by MTT assay and cytokine production using a Cytometric Bead Array kit. RESULTS: Extracts concentrations of 100 µg/mL and 5-hour incubation, reduced more than 93% the growth of all diarrheagenic E. coli pathotypes tested strains and significantly decreased bacterial oxygen consumption, like bacteriostatic antibiotics. After 24-hour incubation methanol extracts had a differential antibacterial effect on each diarrheagenic E. coli pathotypes strain. Echeveria extracts did not have any effect on viability and cytokine production of colorectal adenocarcinoma cells. CONCLUSIONS: Echeveria methanol extracts have a bacteriostatic effect on all diarrheagenic E. coli pathotypes strains, thus potentially they could be used as antibacterial agents on diarrheagenic E. coli pathotypes-contaminated products and on patients with diarrheagenic E. coli pathotypes infections.


Assuntos
Escherichia coli Enteropatogênica , Infecções por Escherichia coli , Células CACO-2 , Criança , Diarreia/microbiologia , Escherichia coli , Infecções por Escherichia coli/microbiologia , Humanos , Extratos Vegetais/farmacologia
20.
J Med Microbiol ; 71(1)2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35037615

RESUMO

Introduction. Bacterial dysentery is one of the greatest causes of morbidity and mortality worldwide. Campylobacter spp. and diarrhoeagenic Escherichia coli (DEC) are recognised as the most common causes of bacterial enteritis in developing countries including India.Hypothesis/Gap statement. Rapid and accurate identification of dysentery causing organisms using molecular methods is essential for better disease management, epidemiology and outbreak investigations.Aim. In view of the limited information available on the dysentery causing agents like Campylobacter spp., enterohemorrhagic E. coli (EHEC)/enteropathogenic E. coli (EPEC) and enteroinvasive E. coli (EIEC)/Shigella in India, this study was undertaken to investigate the presence of these pathogens in human and poultry stool samples by molecular methods.Methodology. In total, 400 human stool samples and 128 poultry samples were studied. Microaerophilic culture along with real-time multiplex PCR with the targets specific to the genus Campylobacter, Campylobacter jejuni, Campylobacter coli, EHEC, EPEC and EIEC/Shigella was performed. Further species confirmation was done using MALDI-TOF MS.Results. On microaerophilic culture, C. coli was isolated in one human sample and two C. jejuni and one C. fetus in poultry samples. On PCR analysis, among human stool samples, typical EPEC (42%) was predominantly seen followed by Campylobacter spp. (19%) and EIEC/Shigella (10%). In contrast, Campylobacter spp. (41%) was predominant in poultry samples, followed by typical EPEC (26%) and EIEC/Shigella (9%). Poly-infections with Campylobacter spp. and DEC were also observed among both sources.Conclusion. The present study documented the increased prevalence of Campylobacter spp. in humans compared with the results of previous studies from India. Typical EPEC was found to be predominant in children less than 5 years of age in this study. The high prevalence of coinfections in the current study indicates that a multiple aetiology of diarrhoea is common in our settings.


Assuntos
Infecções por Campylobacter , Campylobacter , Disenteria , Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Campylobacter/genética , Campylobacter/patogenicidade , Infecções por Campylobacter/epidemiologia , Pré-Escolar , Diarreia/epidemiologia , Diarreia/microbiologia , Disenteria/epidemiologia , Disenteria/microbiologia , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/patogenicidade , Infecções por Escherichia coli/epidemiologia , Fezes , Humanos , Índia , Reação em Cadeia da Polimerase Multiplex , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Shigella/genética
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