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1.
Braz J Microbiol ; 55(3): 2547-2556, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38977544

RESUMO

Campylobacter is gram-negative bacteria considered the predominant genera isolated from poultry samples and associated with gastroenteritis. Due to the problems in conventional cultural methods of time-consuming and technically demanding requirements, a rapid and feasible method for their identification and discrimination of the closely related spp. Including Campylobacter coli, Campylobacter fetus, and Campylobacter jejuni is needed. This study analyzes the chicken and sheep meats samples (n = 125) using culture and pre-enrichment-based Quadraplex real-time PCR by targeting OrfA, CstA, HipO, and 16 S rRNA genes of C. coli, C. fetus, C. jejuni and Campylobacter spp. Respectively. The analysis of 125 chicken and sheep meat samples by culture and real-time PCR showed high concordance between the results of the two methods. The present study show high prevalence of Campylobacter species (35% and 32% from chicken and meat respectively) of which C. jejuni were the most abundant. Reaction efficiencies were between 90 and 110%, and detect as low as 8.9 fg in C. jejuni. The need for quick detection and discrimination methods in sheep and chicken meat can be met using the described Quadraplex real-time PCR methodology.


Assuntos
Campylobacter coli , Campylobacter jejuni , Galinhas , Carne , Reação em Cadeia da Polimerase em Tempo Real , Animais , Galinhas/microbiologia , Ovinos/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Campylobacter coli/genética , Campylobacter coli/isolamento & purificação , Campylobacter coli/classificação , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/classificação , Carne/microbiologia , Campylobacter fetus/genética , Campylobacter fetus/isolamento & purificação , Campylobacter fetus/classificação , Campylobacter/genética , Campylobacter/isolamento & purificação , Campylobacter/classificação , Microbiologia de Alimentos , DNA Bacteriano/genética
2.
J Glob Antimicrob Resist ; 36: 309-318, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38272215

RESUMO

OBJECTIVES: Antimicrobial resistant (AMR) Campylobacter is a global health threat; however, there is limited information on genomic determinants of resistance in low- and middle-income countries. We evaluated genomic determinants of AMR using a collection of whole genome sequenced Campylobacter jejuni and C. coli isolates from Iquitos, Peru. METHODS: Campylobacter isolates from two paediatric cohort studies enriched with isolates that demonstrated resistance to ciprofloxacin and azithromycin were sequenced and mined for AMR determinants. RESULTS: The gyrA mutation leading to the Thr86Ile amino acid change was the only gyrA mutation associated with fluoroquinolone resistance identified. The A2075G mutation in 23S rRNA was present, but three other 23S rRNA mutations previously associated with macrolide resistance were not identified. A resistant-enhancing variant of the cmeABC efflux pump genotype (RE-cmeABC) was identified in 36.1% (35/97) of C. jejuni genomes and 17.9% (12/67) of C. coli genomes. Mutations identified in the CmeR-binding site, an inverted repeat sequence in the cmeABC promoter region that increases expression of the operon, were identified in 24/97 C. jejuni and 14/67 C. coli genomes. The presence of these variants, in addition to RE-cmeABC, was noted in 18 of the 24 C. jejuni and 9 of the 14 C. coli genomes. CONCLUSIONS: Both RE-cmeABC and mutations in the CmeR-binding site were strongly associated with the MDR phenotype in C. jejuni and C. coli. This is the first report of RE-cmeABC in Peru and suggests it is a major driver of resistance to the principal therapies used to treat human campylobacteriosis in this setting.


Assuntos
Antibacterianos , Campylobacter , Humanos , Criança , Antibacterianos/farmacologia , Peru , RNA Ribossômico 23S/genética , Farmacorresistência Bacteriana/genética , Macrolídeos , Campylobacter/genética , Genômica
3.
Mol Phylogenet Evol ; 184: 107786, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37105244

RESUMO

Campylobacter is a bacterial genus associated with community outbreaks and gastrointestinal symptoms. Studies on Campylobacter generally focus on specific pathogenic species such as C. coli and C. jejuni. Currently, there are thousands of publicly available Campylobacter genomes, allowing a more complete assessment of the genus diversity. In this work, we report a network-based analysis of all available Campylobacter genomes to explore the genus structure and diversity, revealing potentially new species and elucidating genus features. We also hypothesize that the previously established Clade III of C. coli is in fact a novel species (referred here as Campylobacter spp12). Finally, we found a negative correlation between pangenome fluidity and saturation coefficient, with potential implications to the lifestyles of distinct Campylobacter species. Since pangenome analysis depends on the number of available genomes, this correlation could help estimate pangenome metrics of Campylobacter species with less sequenced genomes, helping understand their lifestyle and niche adaptation. Together, our results indicate that the Campylobacter genus should be re-evaluated, with particular attention to the interplay between genome structure and niche segregation.


Assuntos
Campylobacter , Campylobacter/genética , Filogenia , Genoma Bacteriano , Genômica/métodos , Bactérias/genética
4.
PLoS Negl Trop Dis ; 16(10): e0010815, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36194603

RESUMO

Campylobacter spp. are a major cause of bacterial diarrhea worldwide and are associated with high rates of mortality and linear growth faltering in children living in low- to middle-income countries (LMICs). Campylobacter jejuni and Campylobacter coli are most often the causative agents of enteric disease among children in LMICs. However, previous work on a collection of stool samples from children under 2 years of age, living in a low resource community in Peru with either acute diarrheal disease or asymptomatic, were found to be qPCR positive for Campylobacter species but qPCR negative for C. jejuni and C. coli. The goal of this study was to determine if whole-genome shotgun metagenomic sequencing (WSMS) could identify the Campylobacter species within these samples. The Campylobacter species identified in these stool samples included C. jejuni, C. coli, C. upsaliensis, C. concisus, and the potential new species of Campylobacter, "Candidatus Campylobacter infans". Moreover, WSMS results demonstrate that over 65% of the samples represented co-infections with multiple Campylobacter species present in a single stool sample, a novel finding in human populations.


Assuntos
Infecções por Campylobacter , Campylobacter , Coinfecção , Campylobacter/genética , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Criança , Coinfecção/epidemiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Fezes/microbiologia , Humanos , Lactente , Metagenômica , Peru/epidemiologia , Reinfecção
5.
PLoS Negl Trop Dis ; 16(10): e0010869, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36251729

RESUMO

A working hypothesis is that less common species of Campylobacter (other than C. jejuni and C. coli) play a role in enteric disease among children in low resource settings and explain the gap between the detection of Campylobacter using culture and culture independent methods. "Candidatus Campylobacter infans" (C. infans), was recently detected in stool samples from children and hypothesized to play a role in Campylobacter epidemiology in low- and middle-income countries (LMIC). This study determined the prevalence of C. infans in symptomatic and asymptomatic stool samples from children living in Iquitos, Peru. Stool samples from 215 children with diarrhea and 50 stool samples from children without diarrhea under the age of two were evaluated using a multiplex qPCR assay to detect Campylobacter spp. (16S rRNA), Campylobacter jejuni / Campylobacter coli (cadF gene), C. infans (lpxA), and Shigella spp. (ipaH). C. infans was detected in 7.9% (17/215) symptomatic samples and 4.0% (2/50) asymptomatic samples. The association between diarrhea and the presence of these targets was evaluated using univariate logistic regressions. C. infans was not associated with diarrhea. Fifty-one percent (75/146) of Campylobacter positive fecal samples were negative for C. jejuni, C. coli, and C. infans via qPCR. Shotgun metagenomics confirmed the presence of C. infans among 13 out of 14 positive C. infans positive stool samples. C infans explained only 20.7% of the diagnostic gap in stools from children with diarrhea and 16.7% of the gap in children without diarrhea. We posit that poor cadF primer performance better explains the observed gap than the prevalence of atypical non-C. jejuni/coli species.


Assuntos
Infecções por Campylobacter , Campylobacter , Criança , Humanos , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/epidemiologia , RNA Ribossômico 16S/genética , Peru/epidemiologia , Campylobacter/genética , Diarreia/epidemiologia , Diarreia/diagnóstico , Fezes
6.
Poult Sci ; 101(7): 101909, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35551000

RESUMO

Campylobacteriosis is one of the most common types of bacterial gastroenteritis affecting humans, and poultry is considered a major source of the causative organism, Campylobacter spp. Broilers may arrive contaminated at slaughterhouses, and transport crates could be considered a potential source of contamination. Thus, cleaning and disinfection procedures are crucial to avoid cross-contamination among flocks. Despite its public health importance in Latin American countries, virulence factors of Campylobacter jejuni remain poorly studied in this region. Thus, this study aimed to: 1) determine the occurrence of contaminated crates at a poultry slaughterhouse, 2) compare the contamination before and after the cleaning and disinfection procedures, and 3) detect virulence-associated genes in C. jejuni strains by PCR. Campylobacter spp. were recovered from 8 of the 10 flocks evaluated, and C. jejuni was detected as the main species. There was no significant difference in the Campylobacter detection or quantification between crates at the reception platform and crates after the cleaning/disinfection processes. However, crates after 24 h of natural drying, presented a significant (P < 0.05) lower amount of Campylobacter cells than before the cleaning and disinfection processes. A negative relationship (R2 = 0.210, P = 0.045) between environmental conditions and Campylobacter quantification was found for transport crates after 24 h of natural drying. There was no significant difference (P > 0.05) in the detection of two C. jejuni virulence genes, flaA (encode a major flagellin protein) and cadF (encode an adhesion and fibronectin-binding protein), among various stages of the cleaning and disinfection processes. Our results demonstrate the high contamination levels of Campylobacter strains in broiler flocks and the potential involvement of poultry transport crates in transmitting these bacteria. This study also suggests that ineffective cleaning and disinfection procedures can increase Campylobacter contamination and facilitate the spread of bacteria in poultry establishments.


Assuntos
Infecções por Campylobacter , Campylobacter jejuni , Campylobacter , Doenças das Aves Domésticas , Matadouros , Animais , Campylobacter/genética , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/prevenção & controle , Infecções por Campylobacter/veterinária , Campylobacter jejuni/genética , Galinhas/microbiologia , Desinfecção/métodos , Microbiologia de Alimentos , Aves Domésticas/microbiologia , Doenças das Aves Domésticas/microbiologia
7.
J Appl Microbiol ; 132(2): 1457-1466, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34465011

RESUMO

AIMS: To generate a murine experimental model of colonization by Campylobacter coli DSPV458. METHODS AND RESULTS: Twelve adult Balb/cCmedc female mice were housed in a treated group (T-G) and a control group (C-G) for 4 weeks. Both experimental groups received antibiotics for 5 days during the first week. The T-G was administered with 6.68log10 CFU of C. coli DSPV458 by oesophageal gavage. Necropsies were performed weekly to evaluate translocation and intestinal colonization in the spleen and liver and in the ileum and cecum respectively. Samples were cultured to quantify intestinal microbiota members. Faeces were cultured weekly for a C. coli DSPV458 count. Campylobacter coli DSPV458 was isolated from all the inoculated mice. The recovered level of C. coli DSPV458 was, on average, 6.9 log10 CFUg-1 , 8.0 log10 CFUg-1 and 1.6 log10 CFUg-1 in faeces, cecum and ileum respectively. Colonization by C. coli DSPV458 does not alter the normal clinical and physiological status. CONCLUSIONS: Campylobacter coli DSPV458 does not have an invasive capacity, and the model is suitable for evaluating strategies to reduce intestinal loads. SIGNIFICANCE AND IMPACT OF STUDY: Farm animals have an important impact on thermotolerant Campylobacter transmission to humans. Extremely few colonization models by C. coli have been reported to date. In food-producing animals, infection is mild or absent and thermotolerant Campylobacter colonize the intestines of animals. Colonization models are specific models that do not cause infection as they do not generally result in diarrhoea or other signs of disease. Therefore, this model will allow to evaluate the evolution of colonization by thermotolerant Campylobacter and the alternative tools development to antibiotics that limit their colonization in food-producing animals.


Assuntos
Infecções por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Animais , Campylobacter/genética , Infecções por Campylobacter/veterinária , Campylobacter coli/genética , Ceco , Fezes , Feminino , Intestinos , Camundongos
8.
Foodborne Pathog Dis ; 19(2): 143-150, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34898274

RESUMO

Campylobacteriosis is one of the most common bacteria causing human gastroenteritis. Poultry is a major reservoir of Campylobacter spp. as well as the main source of transmission. Due to the increased occurrence of campylobacteriosis, poultry slaughterhouses are under pressure to deliver carcasses with low contamination. However, a few studies have been carried out to evaluate Campylobacter contamination of broiler carcasses in Brazilian slaughter lines. Therefore, in this study, we aimed at detecting and quantifying the thermotolerant Campylobacter spp. at different stages of the poultry slaughtering process. The samples were collected from 12 points in three slaughterhouses in southern Brazil, at an interval of 12 months, and were tested for Campylobacter spp. by conventional microbiological technique, the most probable number, and real-time PCR. A total of 432 samples were analyzed. The majority of strains belonged to Campylobacter jejuni (92%), and the flock positivity among the three techniques was similar in most cases. Campylobacter was detected in all slaughtering stages. Although contamination has remained similar (p > 0.05) throughout almost all the slaughter process, evisceration seemed to be an important source of contamination. Our results reinforce the idea that the final carcass quality after the slaughtering process is directly influenced by the level of contamination of the broiler flocks on arrival at the processing plant.


Assuntos
Infecções por Campylobacter , Campylobacter , Matadouros , Animais , Campylobacter/genética , Infecções por Campylobacter/epidemiologia , Galinhas/microbiologia , Microbiologia de Alimentos , Técnicas Microbiológicas , Aves Domésticas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
9.
J Food Prot ; 84(12): 2143-2150, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34324670

RESUMO

ABSTRACT: Campylobacter spp. are considered the most common bacterial cause of human gastroenteritis, one of the four main causes of diarrheal disease worldwide, and they are one of the main foodborne pathogens causing hospitalizations and deaths. Here, 148 strains of Campylobacter spp. isolated from poultry at farms, processing plants, and retail stores in Costa Rica were examined for resistance to six antibiotics. An agar dilution test was used to determine the MIC and susceptibility profiles against doxycycline, ciprofloxacin, nalidixic acid, enrofloxacin, chloramphenicol, and erythromycin. In addition, a pulsed-field gel electrophoresis analysis was carried out to determine the genotype relatedness of a representative subset of the isolates. Approximately 136 (92%) of the 148 analyzed isolates showed resistance to the tested drugs. Nalidixic acid, ciprofloxacin, and enrofloxacin were the antibiotics for which resistance occurred most frequently (91.2, 85.8, and 85.8%, respectively), followed by doxycycline (25.0%), chloramphenicol (5.4%), and erythromycin (2.7%). The profile conferring only resistance to quinolones was the most frequently found, and only 2.0% of the isolates showed resistance to quinolones and macrolides simultaneously. Results showed a high frequency of resistant Campylobacter spp. strains and evidenced the distribution, selection, and circulation of resistant strains along the poultry chain from farms to consumers. Cross-contamination and resistance seem to play important roles in the dissemination of these strains at specific points of the poultry chain, even when control measures are being taken. The establishment of effective surveillance and control strategies represents an essential tool for foodborne diseases mitigation. The rational use of antibiotics, especially those still showing efficacy, should be a priority in both human and veterinary medicine to contain the progress of this phenomenon and its consequences.


Assuntos
Infecções por Campylobacter , Campylobacter jejuni , Campylobacter , Animais , Antibacterianos/farmacologia , Campylobacter/genética , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/veterinária , Campylobacter jejuni/genética , Galinhas , Costa Rica , Farmacorresistência Bacteriana , Microbiologia de Alimentos , Variação Genética , Humanos , Testes de Sensibilidade Microbiana , Aves Domésticas
10.
Am J Trop Med Hyg ; 104(4): 1215-1221, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33534747

RESUMO

Campylobacteriosis is an important contributor to the global burden of acute gastroenteritis (AGE). In Nicaragua, the burden, risk factors, and species diversity for infant campylobacteriosis are unknown. Between June 2017 and December 2018, we enrolled 444 infants from León, Nicaragua, in a population-based birth cohort, conducting weekly household AGE surveillance. First, we described clinical characteristics of symptomatic Campylobacter infections, and then compared clinical characteristics between Campylobacter jejuni/coli and non-jejuni/coli infections. Next, we conducted a nested case-control analysis to examine campylobacteriosis risk factors. Finally, we estimated the population attributable fraction of campylobacteriosis among infants experiencing AGE. Of 296 AGE episodes in the first year of life, Campylobacter was detected in 59 (20%), 39 were C. jejuni/coli, and 20 were non-jejuni/coli species, including the first report of Campylobacter vulpis infection in humans. Acute gastroenteritis symptoms associated with C. jejuni/coli lasted longer than those attributed to other Campylobacter species. In a conditional logistic regression model, chickens in the home (odds ratio [OR]: 3.8, 95% CI: 1.4-9.8), a prior AGE episode (OR: 3.3; 95% CI: 1.4-7.8), and poverty (OR: 0.4; 95% CI: 0.2-0.9) were independently associated with campylobacteriosis. Comparing 90 infants experiencing AGE with 90 healthy controls, 22.4% (95% CI: 11.2-32.1) of AGE episodes in the first year of life could be attributed to Campylobacter infection. Campylobacter infections contribute substantially to infant AGE in León, Nicaragua, with non-jejuni/coli species frequently detected. Reducing contact with poultry in the home and interventions to prevent all-cause AGE may reduce campylobacteriosis in this setting.


Assuntos
Infecções por Campylobacter/epidemiologia , Campylobacter/genética , Coorte de Nascimento , Campylobacter/classificação , Campylobacter/patogenicidade , Infecções por Campylobacter/etiologia , Estudos de Casos e Controles , Pré-Escolar , Fezes/microbiologia , Feminino , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Humanos , Lactente , Recém-Nascido , Masculino , Razão de Chances , Fatores de Risco
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