Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 889
Filtrar
1.
BMC Infect Dis ; 21(1): 109, 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33485326

RESUMO

BACKGROUND: Diarrhoea is a common cause of mortality and morbidity in children under five years old. In Kenya, it has a 21% case fatality with Enteropathogenic E. coli, Campylobacter jejuni, Shigella spp. and Salmonella spp. accounting for 50-60% of the cases. Sulphonamides, tetracycline, ampicillin and trimethoprim/sulfamethoxazole are typically used in the treatment of diarrhoeal diseases but have become ineffective in the face of emerging antimicrobial resistance. The objective of this study was to evaluate the prevalence and antimicrobial susceptibility of Campylobacter jejuni and Shigella species in children under five years of age presenting with diarrhoea at Kapsabet County Referral Hospital in Kenya. METHODS: Faecal samples were collected from 139 children admitted with diarrhoea. Each sample was examined macroscopically for colour, texture, and presence of extraneous material. The samples were then cultured for bacterial growth. Observed bacterial growth was isolated and identified by a series of biochemical tests. Resistance patterns were also evaluated using the Kirby - Bauer Disk diffusion method. The chi - square test and Pearson Correlation Coefficient were used to establish statistical significance. RESULTS: Approximately 33.1% of the total faecal samples tested were positive for enteric pathogens. Shigella spp. demonstrated resistance to erythromycin (91.7%), doxycyclin (83.3%), ampicillin (82.1%), cotrimoxazole (73.1%), minocycline (66.7%) and cefuroxime (54.2%). Campylobacter jejuni also exhibited resistance to erythromycin (87.5%), doxycyclin (75%), ampicillin (73.7%), cotrimoxazole (73.3%) and minocycline (68.8%). CONCLUSIONS: The resistance patterns of Shigella spp. and Campylobacter jejuni reported in this study necessitates the need for a comprehensive multiregional investigation to evaluate the geographical prevalence and antimicrobial resistance distributions of these microorganisms. These findings also support the need for the discovery and development of effective therapeutic alternatives. TRIAL REGISTRATION: Retrospectively registered. Certificate No. 00762.


Assuntos
Antibacterianos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Diarreia/microbiologia , Farmacorresistência Bacteriana Múltipla , Shigella/efeitos dos fármacos , Antibacterianos/uso terapêutico , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/isolamento & purificação , Criança , Pré-Escolar , Diarreia/epidemiologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Disenteria Bacilar/epidemiologia , Disenteria Bacilar/microbiologia , Fezes/microbiologia , Feminino , Hospitais , Humanos , Lactente , Quênia/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Shigella/isolamento & purificação
2.
Int J Food Microbiol ; 341: 109074, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33508583

RESUMO

Campylobacter jejuni (C. jejuni) is one of the most common foodborne pathogens that cause human sickness mostly through the poultry food chain. Cinnamon essential oil (CEO) has excellent antibacterial ability against C. jejuni growth. This study investigated the antibacterial mechanism of CEO against C. jejuni primarily through metabolism, energy metabolism of essential enzymes (AKPase, ß-galactosidase, and ATPase), and respiration metabolism. Results showed that the hexose monophosphate pathway (HMP) was inhibited, and that the enzyme activity of G6DPH substantially decreased upon treatment with CEO. Analysis of the effect of CEO on the expression of toxic genes was performed by the real-time PCR (RT-PCR). The expression levels of the toxic genes cadF, ciaB, fliA, and racR under CEO treatment were determined. Casein/CEO nanospheres were further prepared for the effective inhibition of C. jejuni and characterized by particle-size distribution, zeta-potential distribution, fluorescence, TEM, and GC-MS methods. Finally, the efficiency of CEO and casein/CEO nanospheres in terms of antibacterial activity against C. jejuni was verified. The casein/CEO nanospheres displayed high antibacterial activity on duck samples. The population of the test group decreased from 4.30 logCFU/g to 0.86 logCFU/g and 4.30 logCFU/g to 2.46 logCFU/g at 4 °C and at 25 °C for C. jejuni, respectively. Sensory evaluation and texture analysis were also conducted on various duck samples.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/veterinária , Campylobacter jejuni/efeitos dos fármacos , Caseínas/farmacologia , Cinnamomum zeylanicum/química , Óleos Voláteis/farmacologia , Animais , Infecções por Campylobacter/tratamento farmacológico , Galinhas/microbiologia , Preparações de Ação Retardada/farmacologia , Patos/microbiologia , Metabolismo Energético/efeitos dos fármacos , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Expressão Gênica/efeitos dos fármacos , Glucosefosfato Desidrogenase/antagonistas & inibidores , Humanos , Nanosferas , Via de Pentose Fosfato/efeitos dos fármacos , Aves Domésticas/microbiologia
3.
PLoS One ; 15(7): e0236889, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730330

RESUMO

Australian rates of campylobacteriosis are among the highest in developed countries, yet only limited work has been done to characterize Campylobacter spp. in Australian retail products. We performed whole genome sequencing (WGS) on 331 C. coli and 285 C. jejuni from retail chicken meat, as well as beef, chicken, lamb and pork offal (organs). Campylobacter isolates were highly diverse, with 113 sequence types (STs) including 38 novel STs, identified from 616 isolates. Genomic analysis suggests very low levels (2.3-15.3%) of resistance to aminoglycoside, beta-lactam, fluoroquinolone, macrolide and tetracycline antibiotics. A majority (>90%) of isolates (52/56) possessing the fluoroquinolone resistance-associated T86I mutation in the gyrA gene belonged to ST860, ST2083 or ST7323. The 44 pork offal isolates were highly diverse, representing 33 STs (11 novel STs) and harboured genes associated with resistance to aminoglycosides, lincosamides and macrolides not generally found in isolates from other sources. Prevalence of multidrug resistant genotypes was very low (<5%), but ten-fold higher in C. coli than C. jejuni. This study highlights that Campylobacter spp. from retail products in Australia are highly genotypically diverse and important differences in antimicrobial resistance exist between Campylobacter species and animal sources.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/microbiologia , Campylobacter coli/genética , Campylobacter jejuni/genética , Farmacorresistência Bacteriana/genética , Carne/análise , Animais , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/genética , Campylobacter coli/efeitos dos fármacos , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/isolamento & purificação , Bovinos , Galinhas , DNA Bacteriano/genética , Microbiologia de Alimentos , Testes de Sensibilidade Microbiana , Carne Vermelha , Ovinos , Suínos , Sequenciamento Completo do Genoma
4.
Int J Food Microbiol ; 327: 108656, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32445835

RESUMO

Campylobacter is the world's leading cause of bacterial gastroenteritis, causing nearly 9 million cases of food poisoning in Europe every year. Poultry is considered the main source of Campylobacter infection to humans. The objectives of the study were to determine occurrence of C. jejuni and C. coli in chickens, the antimicrobial resistance, genotypes, and relatedness of the isolates. A total of 177 chicken samples obtained from informal butcher shops (fresh), formal poultry slaughterhouses (refrigerated) and retail market (frozen) were analyzed. Isolation of Campylobacter spp. was conducted according to the ISO 10272-2006 method. Multiplex PCR was used for confirmation and identification of the isolates. The disk diffusion method was used to determine the antimicrobial resistance of the isolates and multilocus sequence typing was used for genotyping. The proportion of samples with Campylobacter spp. was 31.6% among all chicken samples (fresh and refrigerated 47.5%, frozen 0%) C. coli was isolated from 42.4% of chicken samples obtained from butcher shops and from 18.6% of samples obtained in formal slaughterhouses. C. jejuni was isolated from 17.0% of samples obtained in butcher shops and formal slaughterhouses. Campylobacter spp. was not isolated in frozen chicken samples. All tested isolates showed resistance toward ciprofloxacin and susceptibility toward imipenem and all of the isolates were multidrug resistant toward 5 or more antimicrobials. Three sequence types were identified among 10 C. coli isolates and seven sequence types were identified among 10 C. jejuni isolates. Among sequence types, chicken isolates shared similarities of both phenotypic and genetic levels.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter coli , Campylobacter jejuni , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Matadouros , Animais , Antibacterianos/farmacologia , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter coli/efeitos dos fármacos , Campylobacter coli/genética , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Galinhas/microbiologia , Resistência Microbiana a Medicamentos , Doenças Transmitidas por Alimentos/microbiologia , Genótipo , Humanos , Jordânia/epidemiologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase Multiplex , Aves Domésticas/microbiologia , Prevalência
5.
Sci Rep ; 10(1): 5823, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242070

RESUMO

Gastroenteritis is common among children. Campylobacter jejuni is one of the main causative bacterial pathogens, together with Shigella, Salmonella and invasive Escherichia coli. Campylobacteriosis is a zoonotic, usually self-limited disease that does not always require antibiotic treatment. In cases of protracted diarrhoea in healthy children or immunocompromised patients, antibiotic treatment is recommended, and the drug of choice is still macrolides, with very low resistance rates in Campylobacter species. However, it is crucial to isolate the causative organism, because some cases, such as Shigella encephalitis, call for initiation of empiric antibiotic treatment. In this study, we compared the incidence, epidemiology, clinical findings and laboratory results of gastroenteritis with dysentery caused by these organisms in children in our area. C. jejuni was found to be the leading pathogen in children hospitalized with bacterial gastroenteritis, followed by Shigella and Salmonella. Macrolides were the drug of choice for Campylobacter, and ceftriaxone and ciprofloxacin were the best empiric treatments for Shigella and Salmonella, respectively.


Assuntos
Infecções por Campylobacter/epidemiologia , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Antibacterianos/uso terapêutico , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Gastroenterite/tratamento farmacológico , Humanos , Lactente , Israel/epidemiologia , Masculino
6.
Vet Ital ; 56(1)2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32343091

RESUMO

A research was carried out in Italy with the aim of assessing Campylobacter contamination in broilers from breeding to slaughter, of defining the genetic diversity of isolates and their antibiotic resistance. Sampling was carried out in a slaughterhouse, and in farms representative of the most common broiler production in Italy. At farm, the 78.8% (95% C.I.: 74.5%­82.5%) of cloacal samples tested positive for Campylobacter spp. C. jejuni showed higher prevalence in winter than in spring and summer (p < 0.00001, χ2 = 32.9), while C. coli showed an opposite trend (p < 0.00001, χ2= 41.1). At slaughterhouse, the 32.3% (95% C.I.: 30.2%­35.2%) and the 23.9% (95% C.I.: 21.7%­26.3%) of skin samples tested positive for C. jejuni for C. coli, respectively. C. coli showed higher prevalence than C. jejuni at washing (p < 0.05, χ2 = 11.11) and at chilling (p < 0.05, χ2 = 9.26). PFGE revealed high heterogeneity among isolates. Some clones were identified within the same farm in more than one season, suggesting environmental conditions able to support their persistence; other clones resulted to be spatially distant, suggestive of cross­contamination. Both Campylobacter species showed high resistance to nalidixic acid and ciprofloxacin, while resistance to erythromycin was more frequent in C. coli than C. jejuni (p < 0.05; χ2 test).


Assuntos
Infecções por Campylobacter/veterinária , Microbiologia de Alimentos , Doenças das Aves Domésticas/epidemiologia , Matadouros , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Campylobacter/epidemiologia , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Galinhas , Farmacorresistência Bacteriana , Contaminação de Alimentos , Itália/epidemiologia , Testes de Sensibilidade Microbiana , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/microbiologia , Prevalência , Estações do Ano
7.
BMC Infect Dis ; 20(1): 278, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293315

RESUMO

BACKGROUND: Understanding potential risks of multi-drug resistant (MDR) pathogens from the booming poultry sector is a crucial public health concern. Campylobacter spp. are among the most important zoonotic pathogens associated with MDR infections in poultry and human. This study systematically examined potential risks and associated socio-environmental factors of MDR Campylobacter spp. in poultry farms and live bird markets (LBMs) of Bangladesh. METHODS: Microbial culture and PCR-based methods were applied to examine the occurrence and MDR patterns of Campylobacter spp. in potential sources (n = 224) at 7 hatcheries, 9 broiler farms and 4 LBMs in three sub-districts. Antimicrobial residues in broiler meat and liver samples (n = 50) were detected by advanced chromatographic techniques. A questionnaire based cross-sectional survey was conducted on socio-environmental factors. RESULTS: Overall, 32% (71/ 224) samples were found contaminated with Campylobacter spp. In poultry farms, Campylobacter spp. was primarily found in cloacal swab (21/49, 43%), followed by drinking water (8/24, 33%), and meat (8/28, 29%) samples of broilers. Remarkably, at LBMs, Campylobacter spp. was detected in higher prevalence (p < 0.05) in broiler meat (14/26, 54%), which could be related (p < 0.01) to bacterial contamination of drinking water (11/21, 52%) and floor (9/21, 43%). Campylobacter isolates, one from each of 71 positive samples, were differentiated into Campylobacter jejuni (66%) and Campylobacter coli (34%). Alarmingly, 49 and 42% strains of C. jejuni and C. coli, respectively, were observed as MDR, i.e., resistant to three or more antimicrobials, including, tetracycline, amoxicillin, streptomycin, fluoroquinolones, and macrolides. Residual antimicrobials (oxytetracycline, ciprofloxacin and enrofloxacin) were detected in majority of broiler liver (79%) and meat (62%) samples, among which 33 and 19%, respectively, had concentration above acceptable limit. Inadequate personal and environmental hygiene, unscrupulously use of antimicrobials, improper waste disposal, and lack of health surveillance were distinguishable risk factors, with local diversity and compound influences on MDR pathogens. CONCLUSION: Potential contamination sources and anthropogenic factors associated with the alarming occurrence of MDR Campylobacter, noted in this study, would aid in developing interventions to minimize the increasing risks of poultry-associated MDR pathogens under 'One Health' banner that includes poultry, human and environment perspectives.


Assuntos
Antibacterianos/análise , Infecções por Campylobacter/epidemiologia , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Fazendas , Doenças das Aves Domésticas/epidemiologia , Aves Domésticas/microbiologia , Animais , Antibacterianos/uso terapêutico , Bangladesh/epidemiologia , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/microbiologia , Campylobacter coli/genética , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Galinhas/microbiologia , Estudos Transversais , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Prevalência , Fatores de Risco
8.
Vet Microbiol ; 243: 108615, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32273001

RESUMO

Campylobacteriosis caused by C. jejuni is a serious yet common foodborne disease in the U.S. The prevalence of fluoroquinolone-resistant C. jejuni from poultry has continued to increase despite the withdrawal of fluoroquinolone use in the U.S. poultry industry in 2005. To date, no clear selective pressures that explain this effect have been documented. In this study, we investigated limited bioavailability of iron in poultry and enhanced iron uptake and regulation as potential indirect selective pressures conferring fitness advantages in fluoroquinolone-resistant C. jejuni compared to its susceptible wild-type counterpart. Five fluoroquinolone-susceptible C. jejuni isolates were selected from litter collected from commercial broiler farms. Using antibiotic selection, five fluoroquinolone-resistant strains were created. Relative expressions of six genes involved in iron acquisition and regulation were compared between the resistant and susceptible strains using RT-qPCR under normal and iron-limiting conditions. High variability in the relative gene expressions was observed among the strains, with only one resistant strain showing the consistent upregulation of the measured genes compared to the matching susceptible wild-type. Our results suggest that the hypothesis tested in the study may not be an adequate explanation of the molecular mechanism behind the enhanced fitness of fluoroquinolone-resistant C. jejuni compared to susceptible C. jejuni. This study highlights the need for a better understanding of the complex ecology and dynamics of fluoroquinolone resistance in C. jejuni in poultry environment and warrants an examination of fluoroquinolone-resistant C. jejuni strains recovered from the natural broiler chicken environment.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Farmacorresistência Bacteriana/genética , Regulação Bacteriana da Expressão Gênica , Ferro/metabolismo , Animais , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/metabolismo , Fluoroquinolonas/farmacologia , Expressão Gênica , Testes de Sensibilidade Microbiana , Mutação Puntual , Doenças das Aves Domésticas/microbiologia
9.
PLoS One ; 15(4): e0230423, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32236115

RESUMO

Campylobacter jejuni is one of the most prevalent causes of bacterial gastroenteritis worldwide, and it is largely associated with consumption of contaminated poultry. Current Campylobacter control measures at the poultry production level remain insufficient, and hence there is the need for alternative control strategies. We evaluated the potential of the monoterpene (-)-α-pinene for control of C. jejuni in poultry. The antibacterial and resistance-modulatory activities of (-)-α-pinene were also determined against 57 C. jejuni strains. In addition, the anti-quorum-sensing activity of (-)-α-pinene against C. jejuni NCTC 11168 was determined for three subinhibitory concentrations (125, 62.5, 31.25 mg/L) over three incubation times using an autoinducer-2 bioassay based on Vibrio harveyi BB170 bioluminescence measurements. The effects of a subinhibitory concentration of (-)-α-pinene (250 mg/L) on survival of C. jejuni, and in combination with enrofloxacin on fluoroquinolone resistance development in C. jejuni, were determined in a broiler chicken model, by addition of (-)-α-pinene to the broiler water supply. The reduction of C. jejuni numbers by (-)-α-pinene was further determined in broiler chickens that were colonized with either fluoroquinolone-susceptible or -resistant strains, by direct gavage treatment. We observed weak in vitro antimicrobial activity for (-)-α-pinene alone (MIC >500 mg/L), but strong potentiating effects on antibiotics erythromycin and ciprofloxacin against different Campylobacter strains (>512 fold change). After 24 h of treatment of C. jejuni with (-)-α-pinene, its quorum-sensing signaling was reduced by >80% compared to the untreated control. When given in the drinking water, (-)-α-pinene did not show any significant inhibitory effects on the level of C. jejuni in the colonized chickens, and did not reduce fluoroquinolone resistance development in combination with enrofloxacin. Conversely, when (-)-α-pinene was administered by direct gavage, it significantly reduced the number of fluoroquinolone susceptible C. jejuni in the colonized broiler chickens. These results demonstrate that (-)-α-pinene modulates quorum-sensing in Campylobacter, potentiates antibiotics against different Campylobacter strains, and reduces Campylobacter colonization in broiler chickens.


Assuntos
Antibacterianos/farmacologia , Monoterpenos Bicíclicos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Animais , Antibacterianos/uso terapêutico , Monoterpenos Bicíclicos/uso terapêutico , Infecções por Campylobacter/patologia , Infecções por Campylobacter/prevenção & controle , Campylobacter jejuni/fisiologia , Ceco/microbiologia , Galinhas , Ciprofloxacino/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Eritromicina/farmacologia , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Testes de Sensibilidade Microbiana , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/prevenção & controle
10.
Appl Environ Microbiol ; 86(9)2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32111591

RESUMO

Campylobacter spp. have been recognized as major foodborne pathogens worldwide. An increasing frequency of antibiotic-resistant pathogens, including Campylobacter spp., have been identified to transmit from food products to humans and cause severe threats to public health. To better mitigate the antibiotic resistance crisis, rapid detection methods are required to provide timely antimicrobial resistance surveillance data for agri-food systems. Herein, we developed a polymer-based microfluidic device for the identification and antimicrobial susceptibility testing (AST) of Campylobacter spp. An array of bacterial incubation chambers were created in the microfluidic device, where chromogenic medium and antibiotics were loaded. The growth of Campylobacter spp. was visualized by color change due to chromogenic reactions. This platform achieved 100% specificity for Campylobacter identification. Sensitive detection of multiple Campylobacter species (C. jejuni, C. coli, and C. lari) was obtained in artificially contaminated milk and poultry meat, with detection limits down to 1 × 102 CFU/ml and 1 × 104 CFU/25 g, respectively. On-chip AST determined Campylobacter antibiotic susceptibilities by the lowest concentration of antibiotics that can inhibit bacterial growth (i.e., no color change observed). High coincidences (91% to 100%) of on-chip AST and the conventional agar dilution method were achieved against several clinically important antibiotics. For a presumptive colony, on-chip identification and AST were completed in parallel within 24 h, whereas standard methods, including biochemical assays and traditional culture-based AST, take several days for multiple sequential steps. In conclusion, this lab-on-a-chip device can achieve rapid and reliable detection of antibiotic-resistant Campylobacter spp.IMPORTANCE Increasing concerns of antibiotic-resistant Campylobacter spp. with regard to public health emphasize the importance of efficient and fast detection. This study described the timely identification and antimicrobial susceptibility testing of Campylobacter spp. by using a microfluidic device. Our developed method not only reduced the total analysis time, but it also simplified food sample preparation and chip operation for end users. Due to the miniaturized size of the lab-on-a-chip platform, the detection was achieved by using up to 1,000 times less of the reagents than with standard reference methods, making it a competitive approach for rapid screening and surveillance study in food industries. In addition, multiple clinically important Campylobacter species (C. jejuni, C. coli, and C. lari) could be tested by our device. This device has potential for wide application in food safety management and clinical diagnostics, especially in resource-limited regions.


Assuntos
Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Campylobacter lari/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana/métodos , Microfluídica/métodos , Antibacterianos/farmacologia , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Campylobacter lari/isolamento & purificação , Dispositivos Lab-On-A-Chip
11.
Appl Environ Microbiol ; 86(8)2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32033955

RESUMO

In a structured survey of all major chicken-meat producers in Australia, we investigated the antimicrobial resistance (AMR) and genomic characteristics of Campylobacter jejuni (n = 108) and C. coli (n = 96) from cecal samples of chickens at slaughter (n = 200). The majority of the C. jejuni (63%) and C. coli (86.5%) samples were susceptible to all antimicrobials. Fluoroquinolone resistance was detected among both C. jejuni (14.8%) and C. coli (5.2%), although this only included three sequence types (STs) and one ST, respectively. Multidrug resistance among strains of C. jejuni (0.9%) and C. coli (4.1%) was rare, and fluoroquinolone resistance, when present, was never accompanied by resistance to any other agent. Comparative genome analysis demonstrated that Australian isolates were found dispersed on different branches/clusters within the international collection. The major fluoroquinolone-resistant STs of C. jejuni (ST7323, ST2083, and ST2343) and C. coli (ST860) present in Australian chickens were similar to those of international isolates and have been reported previously in humans and animals overseas. The detection of a subpopulation of Campylobacter isolates exclusively resistant to fluoroquinolone was unexpected since most critically important antimicrobials such as fluoroquinolones are excluded from use in Australian livestock. A number of factors, including the low level of resistance to other antimicrobials, the absence of fluoroquinolone use, the adoption of measures for preventing spread of contagion between flocks, and particularly the genomic identities of isolates, all point to humans, pest species, or wild birds as being the most plausible source of organisms. This study also demonstrates the need for vigilance in the form of surveillance for AMR based on robust sampling to manage AMR risks in the food chain.IMPORTANCE Campylobacter is one of the most common causes of gastroenteritis in humans, with infections frequently resulting from exposure to undercooked poultry products. Although human illness is typically self-limiting, a minority of cases do require antimicrobial therapy. Ensuring that Campylobacter originating from meat chickens does not acquire resistance to fluoroquinolones is therefore a valuable outcome for public health. Australia has never legalized the use of fluoroquinolones in commercial chickens and until now fluoroquinolone-resistant Campylobacter has not been detected in the Australian poultry. This structured survey of meat chickens derived from all major Australian producers describes the unexpected emergence of fluoroquinolone resistance in Campylobacter jejuni and C. coli Genetic characterization suggests that these isolates may have evolved outside the Australian poultry sector and were introduced into poultry by humans, pest species, or wild birds. The findings dramatically underline the critical role of biosecurity in the overall fight against antimicrobial resistance.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/veterinária , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Farmacorresistência Bacteriana , Fluoroquinolonas/farmacologia , Doenças das Aves Domésticas/epidemiologia , Animais , Austrália/epidemiologia , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter coli/fisiologia , Campylobacter jejuni/fisiologia , Galinhas , Testes de Sensibilidade Microbiana , Doenças das Aves Domésticas/microbiologia
12.
Prev Vet Med ; 176: 104935, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32109783

RESUMO

Campylobacter spp. are the leading causes of bacterial human gastroenteritis worldwide; being poultry farms the main source of infections. In order to obtain information on prevalence and diversity of Campylobacter-infected flocks in the North of Spain, fourteen farms were studied between autumn and spring in 2014 and 2015, respectively. Moreover, virulence genes involved in pathogenicity and antimicrobial resistance were investigated. A survey about preventive hygiene practices at farms was performed to determine the risky practices that could contribute to the presence of Campylobacter in this step of the poultry food chain. Testing the presence of Campylobacter spp. showed 43 % of the farms were positive during autumn, whereas only 31 % were positive in spring. A very high prevalence within-flock was observed (43.1 % to 88.6 %) and C. jejuni was the most prevalent species in both periods. Genotyping by pulsed field gel electrophoresis (PFGE) showed a high heterogeneity among farms (309 isolates clustered into 21 pulsotypes). Virulence genes were present in all C. jejuni isolates while cdtA and cdtC were absent in C. coli. On the contrary, the latter showed higher antimicrobial resistance than C. jejuni. This study suggests that environment might be one of the main sources for Campylobacter transmission, as water supply seemed to be a clear cause of the contamination in a specific farm. However, in other farms other environmental factors contributed to the contamination, confirming the multifactorial origin of Campylobacter colonization in broilers. Therefore, biosecurity measures in farms are crucial to reduce Campylobacter contamination, which may have important implications for human and animal health.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Galinhas , Farmacorresistência Bacteriana/genética , Genótipo , Doenças das Aves Domésticas/epidemiologia , Animais , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter coli/genética , Campylobacter coli/patogenicidade , Campylobacter jejuni/genética , Campylobacter jejuni/patogenicidade , Doenças das Aves Domésticas/microbiologia , Prevalência , Estações do Ano , Espanha/epidemiologia , Virulência/genética
13.
Vet Microbiol ; 240: 108504, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31902497

RESUMO

Campylobacter jejuni (C. jejuni) is a predominant cause of foodborne illness in humans, while its colonization in chickens is usually asymptomatic. Antibiotics are not routinely used to treat chickens against C. jejuni, but in the face of other bacterial diseases, C. jejuni may be exposed to antibiotics. In this study, chickens were treated with antibiotics (AT) to modify the gut microbiota composition and compared with untreated chickens (Conv) with respect to changes in C. jejuni-colonization and bacterial-intestine interaction. Groups of AT and Conv chickens were inoculated after an antibiotic-withdrawal time of eight days with one of three different C. jejuni isolates to identify possible strain variations. Significantly higher numbers of colony forming units of C. jejuni were detected in the cecal content of AT birds, with higher colonization rates in the spleen and liver compared to Conv birds independent of the inoculated strain (p < 0.05). Clinical signs and histopathological lesions were only observed in C. jejuni-inoculated AT birds. For the first time we demonstrated C. jejuni invasion of the cecal mucosa in AT chickens and its inter- and intracellular localization by using antigen-straining, and electronic microscopy. This study provides the first circumstantial evidence that antibiotic treatment with lasting modification of the microbiota may provide a suitable environment for C. jejuni invasion also in chickens which may subsequently increase the risk of C. jejuni-introduction into the food chain.


Assuntos
Antibacterianos/uso terapêutico , Aderência Bacteriana/efeitos dos fármacos , Infecções por Campylobacter/veterinária , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/patogenicidade , Ceco/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Infecções por Campylobacter/microbiologia , Ceco/efeitos dos fármacos , Galinhas/microbiologia , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Doenças das Aves Domésticas/microbiologia
14.
J Food Sci ; 85(1): 157-164, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31909483

RESUMO

Campylobacter species are known as biofilm-forming bacteria in food systems. The aim of this study was to evaluate the antimicrobial and antibiofilm effects of cinnamaldehyde against Campylobacter jejuni and Campylobacter coli isolated from chicken meat. The biofilm-forming C. jejuni and C. coli strains from chicken meat were investigated using minimum inhibitory concentration (MIC) and Campylobacter spp. characteristics. The MIC value was 31.25 µg/mL for the Campylobacter strains tested. Cinnamaldehyde had an inhibition and degradation effect on Campylobacter biofilms at concentrations > 15.63 µg/mL. Campylobacter strains treated with 15.63 µg/mL CA exhibited significantly decreased autoaggregation, motility, exopolysaccharide production, and soluble protein. In addition, Campylobacter biofilms formed on stainless steel were degraded following cinnamaldehyde treatment, as determined by scanning electron microscopy. Taken together, these results suggest that cinnamaldehyde constitutes a potential natural preservative against Campylobacter and a nontoxic biofilm remover that could be applied to control food poisoning in the poultry manufacturing-related food industry. PRACTICAL APPLICATION: Cinnamaldehyde was able to effectively remove the biofilm of Campylobacter in the small crack of stainless steel. Cinnamaldehyde has a potential to replace the synthetic antimicrobial and/or antibiofilm agent as well as has a positive influence on consumer concern for the food safety issues of the poultry industries.


Assuntos
Acroleína/análogos & derivados , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Campylobacter coli/efeitos dos fármacos , Acroleína/farmacologia , Animais , Bactérias/efeitos dos fármacos , Campylobacter coli/fisiologia , Campylobacter jejuni/efeitos dos fármacos , Galinhas/microbiologia , Carne/microbiologia , Testes de Sensibilidade Microbiana , Aço Inoxidável/análise
15.
PLoS One ; 15(1): e0227535, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31999701

RESUMO

BACKGROUND: Campylobacter jejuni is the most common bacterial cause of human infectious intestinal disease. METHODS: We genome sequenced 601 human C. jejuni isolates, obtained from two large prospective studies of infectious intestinal disease (IID1 [isolates from 1993-1996; n = 293] and IID2 [isolates from 2008-2009; n = 93]), the INTEGRATE project [isolates from 2016-2017; n = 52] and the ENIGMA project [isolates from 2017; n = 163]. RESULTS: There was a significant increase in the prevalence of the T86I mutation conferring resistance to fluoroquinolone between each of the three later studies (IID2, INTEGRATE and ENIGMA) and IID1. Although the distribution of major multilocus sequence types (STs) was similar between the studies, there were changes in both the abundance of minority STs associated with the T86I mutation, and the abundance of clones within single STs associated with the T86I mutation. DISCUSSION: Four population-based studies of community diarrhoea over a 25 year period revealed an increase over time in the prevalence of the T86I amongst isolates of C. jejuni associated with human gastrointestinal disease in the UK. Although associated with many STs, much of the increase is due to the expansion of clones associated with the resistance mutation.


Assuntos
Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/farmacologia , Enteropatias/microbiologia , Mutação , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/fisiologia , Criança , Genoma Bacteriano/genética , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único , Prevalência , Reino Unido
16.
Vet Microbiol ; 241: 108553, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31928700

RESUMO

The objectives of this work were to evaluate ß-lactamase-mediated ß-lactam resistance in Campylobacter coli and Campylobacter jejuni isolates obtained from broiler chickens, expression of the blaOXA-61 gene in relation to ß-lactamase production, and the possible association between blaOXA-61 gene expression and the action of inhibitors when combined with ß-lactams. All strains were tested by disk diffusion and nitrocefin methods to assess antibiotic susceptibility and ß-lactamase production, respectively. PCR and qPCR amplification were performed to evaluate qualitative and quantitative blaOXA-61 expression. Campylobacter spp. showed a high level of resistance to the most of antimicrobials tested. C. coli strains were ampicillin resistant and blaOXA-61 positive, and 59 out of 60 isolates were positive in the nitrocefin test. Twenty C. jejuni isolates were positive for blaOXA-61 and the nitrocefin test, although two isolates were ampicillin sensitive. Amoxicillin/clavulanic acid and ticarcillin/clavulanic acid do not seem to be active against C. coli, as 73.3 %, and 88.3 % of isolates were resistant to amoxicillin/clavulanic acid and ticarcillin/clavulanic acid, respectively. C. jejuni was not susceptible to amoxicillin/clavulanic acid, with 90 % of the strains showing resistance, whereas ticarcillin associated with clavulanic acid was significantly more efficient than ticarcillin alone (P < 0.01), with 90 % of the strains found to be susceptible. An association between blaOXA-61 expression and amoxicillin/clavulanic acid and ticarcillin/clavulanic acid resistance (P = 0.0001) was seen in C. coli, as well as in C. jejuni for ampicillin/sulbactam (P = 0.0001). Our results suggest that the clavulanic acid only shows an inhibitory effect on C. jejuni when combined with ticarcillin and that the inhibitors action is lower if the blaOXA-61 gene is highly expressed.


Assuntos
Antibacterianos/farmacologia , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Resistência beta-Lactâmica , Inibidores de beta-Lactamases/farmacologia , Algoritmos , Resistência a Ampicilina , Animais , Campylobacter coli/genética , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Galinhas , Ácidos Clavulânicos/farmacologia , Cloaca/microbiologia , Expressão Gênica , RNA Bacteriano/química , RNA Bacteriano/isolamento & purificação , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Ticarcilina/farmacologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
17.
PLoS One ; 15(1): e0227833, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951631

RESUMO

The aim of this study is to characterize the antimicrobial resistance of Campylobacter jejuni recovered from diarrheal patients in Belgium, focusing on the genetic diversity of resistant strains and underlying molecular mechanisms of resistance among Campylobacter jejuni resistant strains isolated from diarrheal patients in Belgium. Susceptibility profile of 199 clinical C. jejuni isolates was determined by minimum inhibitory concentrations against six commonly-used antibiotics (ciprofloxacin, nalidixic acid, tetracycline, streptomycin, gentamicin, and erythromycin). High rates of resistance were observed against nalidixic acid (56.3%), ciprofloxacin (55.8%) and tetracycline (49.7%); these rates were similar to those obtained from different national reports in broilers intended for human consumption. Alternatively, lower resistance rates to streptomycin (4.5%) and erythromycin (2%), and absolute sensitivity to gentamicin were observed. C. jejuni isolates resistant to tetracycline or quinolones (ciprofloxacin and/or nalidixic acid) were screened for the presence of the tetO gene and the C257T mutation in the quinolone resistance determining region (QRDR) of the gyrase gene gyrA, respectively. Interestingly, some of the isolates that displayed phenotypic resistance to these antimicrobials lacked the corresponding genetic determinants. Among erythromycin-resistant isolates, a diverse array of potential molecular resistance mechanisms was investigated, including the presence of ermB and mutations in the 23S rRNA gene, the rplD and rplV ribosomal genes, and the regulatory region of the cmeABC operon. Two of the four erythromycin-resistant isolates harboured the A2075G transition mutation in the 23S rRNA gene; one of these isolates exhibited further mutations in rplD, rplV and in the cmeABC regulatory region. This study expands the current understanding of how different genetic determinants and particular clones shape the epidemiology of antimicrobial resistance in C. jejuni in Belgium. It also reveals many questions in need of further investigation, such as the role of other undetermined molecular mechanisms that may potentially contribute to the antimicrobial resistance of Campylobacter.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Diarreia/microbiologia , Farmacorresistência Bacteriana , Infecções por Campylobacter/tratamento farmacológico , Campylobacter jejuni/efeitos dos fármacos , Diarreia/tratamento farmacológico , Genes Bacterianos/efeitos dos fármacos , Humanos , Tipagem de Sequências Multilocus , Mutação/efeitos dos fármacos
18.
Mol Biol Rep ; 47(1): 671-681, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31749118

RESUMO

Campylobacter jejuni is the most common bacterial cause of foodborne diarrheal disease worldwide and is among the antimicrobial resistant "priority pathogens" that pose greatest threat to public health. The genomes of two C. jejuni isolated from poultry meat sold on the retail market in Southern Brazil phenotypically characterized as multidrug-resistant (CJ100) and susceptible (CJ104) were sequenced and analyzed by bioinformatic tools. The isolates CJ100 and CJ104 showed distinct multilocus sequence types (MLST). Comparative genomic analysis revealed a large number of single nucleotide polymorphisms, rearrangements, and inversions in both genomes, in addition to virulence factors, genomic islands, prophage sequences, and insertion sequences. A circular 103-kilobase megaplasmid carrying virulence factors was identified in the genome of CJ100, in addition to resistance mechanisms to aminoglycosides, beta-lactams, macrolides, quinolones, and tetracyclines. The molecular characterization of distinct phenotypes of foodborne C. jejuni and the discovery of a novel virulence megaplasmid provide useful data for pan-genome and large-scale studies to monitor the virulent C. jejuni in poultry meat is warranted.


Assuntos
Antibacterianos/farmacologia , Campylobacter jejuni , Farmacorresistência Bacteriana Múltipla/genética , Carne/microbiologia , Animais , Brasil , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/patogenicidade , Genoma Bacteriano/genética , Genômica , Tipagem de Sequências Multilocus , Plasmídeos/genética , Aves Domésticas , Fatores de Virulência/genética
19.
Appl Environ Microbiol ; 86(6)2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31862718

RESUMO

Increasing evidence exists for the role that cattle play in the epidemiology of campylobacteriosis. In this study, the prevalence and distribution of Campylobacter jejuni were longitudinally examined at the subspecies level in the beef cattle production continuum. Animals were subdivided into two groups: those that were not administered antibiotics and those that were administered the antimicrobial growth promoter chlortetracycline and sulfamethazine (AS700). Samples were longitudinally collected throughout the confined feeding operation (CFO) period and during the slaughter process, and C. jejuni was isolated and genotyped to assess subtype richness and to elucidate transmission dynamics from farm to fork. The bacterium was frequently isolated from cattle, and the bacterial densities shed in feces increased over the CFO period. Campylobacter jejuni was also isolated from digesta, hides, the abattoir environment, and carcasses. The administration of AS700 did not conspicuously reduce the C. jejuni densities in feces or within the intestine but significantly reduced the bacterial densities and the diversity of subtypes on abattoir samples. All cattle carried multiple subtypes, including clinically relevant subtypes known to represent a risk to human health. Instances of intra-animal longitudinal transmission were observed. Although clinically relevant subtypes were transmitted to carcasses via direct contact and aerosols, the bacterium could not be isolated nor could its DNA be detected in ground beef regardless of treatment. Although the evidence indicated that beef cattle represent a significant reservoir for C. jejuni, including high-risk subtypes strongly associated with the bovine host, they do not appear to represent a significant risk for direct foodborne transmission. This implicates alternate routes of human transmission.IMPORTANCE Limited information is available on the transmission of Campylobacter jejuni subtypes in the beef production continuum and the foodborne risk posed to humans. Cattle were colonized by diverse subtypes of C. jejuni, and the densities of the bacterium shed in feces increased during the confined feeding period. Campylobacter jejuni was readily associated with the digesta, feces, and hides of cattle entering the abattoir, as well as the local environment. Moreover, C. jejuni cells were deposited on carcasses via direct contact and aerosols, but the bacterium was not detected in the ground beef generated from contaminated carcasses. We conclude that C. jejuni bacterial cells associated with beef cattle do not represent a significant risk through food consumption and suggest that clinically relevant subtypes are transmitted through alternate routes of exposure.


Assuntos
Criação de Animais Domésticos , Antibacterianos/uso terapêutico , Infecções por Campylobacter/veterinária , Campylobacter jejuni/fisiologia , Doenças dos Bovinos/transmissão , Microbiologia de Alimentos , Matadouros , Alberta , Animais , Derrame de Bactérias/efeitos dos fármacos , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/transmissão , Campylobacter jejuni/classificação , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/isolamento & purificação , Bovinos , Doenças dos Bovinos/microbiologia , Clortetraciclina/uso terapêutico , Combinação de Medicamentos , Fezes/microbiologia , Sulfametazina/uso terapêutico
20.
APMIS ; 128(1): 41-47, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31692136

RESUMO

Campylobacteriosis is one of the most frequently reported zoonoses worldwide. The well-documented increase in the ciprofloxacin resistance has increased the importance of rapid detection of the resistance. The incidence of ciprofloxacin resistance was investigated using real-time PCR. Identification of one hundred and fifty-eight strains was performed by PCR. Minimum inhibitory concentration (MIC) of ciprofloxacin was determined by Epsilometer test. Following the confirmation of the efficiencies of singleplex real-time PCR methods using two different probes, a cytosine to thymine point mutation at codon 86 was detected by allelic discrimination. Of the 158 strains, 114 (72.2%) were determined to be resistant to ciprofloxacin. The MIC50 and the MIC90 of ciprofloxacin were found to be 8 and ≥32 mg/L, respectively. By real-time PCR, the presence of the mutation was confirmed in all, but one, resistant strains and the absence of the mutation was demonstrated in all, but one, susceptible strains. The rate of resistance is high among C. jejuni strains and ciprofloxacin should not be used in the treatment of such infections in Turkey. A cytosine to thymine mutation is the most frequently detected mechanism for the resistance. Real-time PCR can be used for the quick screening of the resistance.


Assuntos
Antibacterianos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Ciprofloxacino/farmacologia , Farmacorresistência Bacteriana/genética , Mutação Puntual , Alelos , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Eletroforese em Gel de Campo Pulsado , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Fenótipo , Prevalência , Turquia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...