scholarly journals Citrobacter braakii Yield False-Positive Identification as Salmonella, a Note of Caution

Foods ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2177
Author(s):  
Joanna Pławińska-Czarnak ◽  
Karolina Wódz ◽  
Magdalena Kizerwetter-Świda ◽  
Tomasz Nowak ◽  
Janusz Bogdan ◽  
...  

Background: Globally, Salmonella enterica is one of the leading causes of foodborne illness in humans. Food of animal origin is obligatorily tested for the presence of this pathogen. Unfortunately, in meat and meat products, this is often hampered by the presence of background microbiota, which may present as false-positive Salmonella. Methods: For the identification of Salmonella spp. from meat samples of beef, pork, and poultry, the authorized detection method is PN-EN ISO 6579-1:2017-04 with the White–Kauffmann–Le Minor scheme, two biochemical tests: API 20E and VITEK II, and a real-time PCR-based technique. Results: Out of 42 presumptive strains of Salmonella, 83.3% Salmonella enterica spp. enterica, 14.3% Citrobacter braakii, and 12.4% Proteus mirabilis were detected from 180 meat samples. Conclusions: Presumptive strains of Salmonella should be identified based on genotypic properties such as DNA-based methods. The aim of this study was the isolation and identification of Salmonella spp. from miscellaneous meat sorts: beef, pork, and poultry.

Author(s):  
Nuzhat Hassan ◽  
Charanjit S. Randhawa ◽  
Ashwani Kumar ◽  
Mudit Chandra ◽  
Naresh Kumar Sood ◽  
...  

The study was aimed at dairy cattle and buffaloes presented with the history of chronic diarrhea to isolate and detect Salmonella spp. Fecal samples were collected directly from the rectum of diarrheic cattle. Isolation and identification of the microorganisms was performed and confirmed on the basis of their morphology, staining, cultural, biochemical tests and sero-typing. Salmonella positive animals presented variable degree and frequency of diarrhea. Salmonellosis was confirmed in seven per cent of cattle and buffaloes suffering from chronic diarrhea. The serotype detected in the 7 Salmonella strains was Salmonella enterica subsp. enterica serovar Reading. Salmonella isolates recovered from dairy cattle had relatively variable resistance to various antimicrobial agents. The antimicrobial susceptibility pattern of the isolates showed isolates were resistant to amoxicillin, tetracycline, ampicillin, ceftriaxone. Whereas 87.5 percent, 75.0 per cent and 62.5 percent susceptible to ciprofloxacin, gentamicin and co-trimoxazole respectively. This study provides updated information on the bio-incidence and susceptibility patterns of Salmonella in dairy animals suffering chronic diarrhea. Isolation and serotyping of Salmonella enterica subsp. enterica serovar Reading is new to the study and contribute to our understanding that there is shift in increases in susceptibility of dairy herds to acquire new strains.


2021 ◽  
Vol 1 (1) ◽  
pp. 84-89

The article provides an overview of methods for detecting bacteria of the Escherichia coli group, including E. coli. This group of microorganisms is one of the main standardized indicators when assessing the quality of food products of animal origin. Analysis of microbiological studies of chilled beef meat samples showed that when determining the presence of BGKP in samples, using traditional and modern methods of analysis, the results do not differ significantly. For the differentiation of enterobacteria, Endo's medium and a selective agar chromogenic medium Chromocult Coliform Agar (Merck, Germany) were used. The amount of BGKP in 1 cm3 of meat products varied from 0.3 × 102 CFU / cm3 to 1.6 × 102-1.8 × 102 CFU / cm3. When microcopying smears in all samples, small rods with rounded ends were found, according to Gram they were negatively stained. When growing on Endo agar, colonies of red color with a metallic sheen were noted; on a chromogenic medium, the growth of violet colonies was noted. During the tests, microorganisms were identified from the samples, representatives of the genera: Escherichia, Enterobacter, Citrobacter. The use of modern methods of analysis made it possible to reduce the labor costs that were spent on the preparation of media, and also made it possible to exclude the stages of confirmatory biochemical tests, thanks to the use of culture media with markers of specific enzymatic activity.


2021 ◽  
Vol 72 (1) ◽  
pp. 2723
Author(s):  
S ABUSEIR ◽  
M ABED AL-DAYM ◽  
G ADWAN ◽  
N KHRAIM

Salmonella spp. are one of a major public health concerns worldwide, as well as it is the most frequently isolated foodborne pathogen. Human illness with Salmonella spp. is often due to the consumption of contaminated food of animal origin such as eggs or their products and poultry meat. The prevalence of this pathogen in egg-laying poultry farms and in broiler farms is an important public health risk factor. Salmonella enterica serovar Enteritidis has been the major cause of foodborne salmonellosis in humans. Data on the prevalence of Salmonella spp. in the Palestinian territories’ poultry flocks is lacking. The objective of this study was to investigate the prevalence of Salmonella spp. in local layer and broiler flocks, and to find out the rate of S. Enteritidis among the isolated samples. A total of 1180 cloacal swabs were collected from several layer and broiler farms from different locations in the West Bank, Palestine. Identification of Salmonella spp. was carried out using conventional and serological methods. Molecular methods using Polymerase Chain Reaction was used for confirmation of Salmonella spp., and to detect the presence of S. Enteritidis among the isolated Salmonella spp. Results of the current study showed that, the rate of Salmonella spp. in the sample tested from layer and broiler farms was 10.7% (65/608) and 4.7% (27/572), respectively. In addition, the prevalence rate of S. Enteritidis among other Salmonella spp. was 0.0% and 14.8% for layer and broiler farms, respectively. It is highly recommended that further studies should be conducted, including high number of samples with serotyping and molecular characterization of the positive samples.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Abdelazeem M. Algammal ◽  
Mahmoud E. Elsayed ◽  
Hany R. Hashem ◽  
Hazem Ramadan ◽  
Norhan S. Sheraba ◽  
...  

Abstract Background Meat-products are considered an enriched media for mycotoxins. This study aimed to investigate the prevalence of toxigenic Aspergillus species in processed meat samples, HPLC-quantitative measurement of aflatoxin B1 and ochratoxin A residues, and molecular sequencing of aflR1 and pks genes. One hundred and twenty processed beef meat specimens (basterma, sausage, and minced meat; n = 40 for each) were collected from Ismailia Province, Egypt. Samples were prepared for total mold count, isolation, and identification of Aspergillus species. All samples were analyzed for the production of both Aflatoxin B1 and Ochratoxin A mycotoxins by HPLC. Molecular identification of Aspergillus flavus and Aspergillus ochraceus was performed using PCR amplification of the internal transcribed spacer (ITS) region; furthermore, the aflR1 and pks genes were sequenced. Results The total mold count obtained from sausage samples was the highest one, followed by minced meat samples. The prevalence of A. flavus was (15%), (7.5%), and (10%), while the prevalence of A. ochraceus was (2.5%), (10%), and (0%) in the examined basterma, sausage, and minced meat samples, respectively. Using PCR, the ITS region was successfully amplified in all the tested A. flavus and A. ochraceus strains. Aflatoxin B1 was detected in six basterma samples (15%). Moreover, the ochratoxin A was detected only in four sausage samples (10%). The aflR1 and pks genes were amplified and sequenced successfully and deposited in the GenBank with accession numbers MF694264 and MF694264, respectively. Conclusions To the best of our knowledge, this is the first report concerning the HPLC-Molecular-based approaches for the detection of aflatoxin B1 and ochratoxin A in processed beef meat in Egypt. The production of aflatoxin B1 and ochratoxin A in processed meat constitutes a public health threat. Aflatoxin B1 is commonly associated with basterma samples. Moreover, ochratoxin A was detected frequently in sausage samples. The routine inspection of mycotoxins in processed meat products is essential to protect human consumers.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Endrias Zewdu Gebremedhin ◽  
Gezahegn Tafesse Soboka ◽  
Bizunesh Mideksa Borana ◽  
Lencho Megersa Marami ◽  
Edilu Jorga Sarba ◽  
...  

Background. Salmonella has been recognized as a major cause of food-borne illness associated with the consumption of food of animal origin. The present cross-sectional study was conducted from December 2017 to May 2018 in Ambo and Holeta towns to assess the prevalence, risk factors, and antimicrobial susceptibility patterns of nontyphoidal Salmonella isolates from raw beef samples from abattoirs, butchers, and restaurants in Ambo and Holeta towns, Oromia region, Ethiopia. Methods. A total of 354 beef samples were collected from abattoirs, butchers, and restaurants. Salmonella isolation and identification were carried out using standard bacteriological methods recommended by the International Organization for Standardization. Antimicrobial susceptibility testing was performed using the disk diffusion method. Besides, a structured questionnaire was used to collect sociodemographic data and potential risk factors for contamination of meat. Chi-square tests and logistic regression were used for data analyses. Results. Of the total 354 meat samples examined, 20 (5.7%, 95% confidence interval (CI): 3.5–8.6) were positive for Salmonella. Two serotypes belonging to S. typhimurium (11 isolates) and I:4,5,12: i:- (9 isolates) were identified. The Salmonella detection rate in abattoirs, butchers, and restaurants was 4.2% (5/118), 8.5% (10/118), and 4.2% (5/118), respectively. The antimicrobial susceptibility test showed that 40%, 30%, and 20% of the Salmonella isolates were resistant to azithromycin, amoxicillin, and ceftriaxone, respectively. The odds of Salmonella isolation when meat handlers are illiterate were 7.8 times higher than those when they are educated to the level of secondary and above ( P = 0.032 ). Similarly, the likelihood of Salmonella isolation was 6.3 and 7.6 times higher among workers of butcher and restaurants, respectively, who had no training ( P = 0.003 ) and no knowledge ( P = 0.010 ) on food safety and hygiene. Conclusions. The study showed widespread multidrug-resistant Salmonella isolates in the study areas. Therefore, raw meat consumption and indiscriminate use of antimicrobial drugs should be discouraged. Provision of food safety education for meat handlers and further surveillance of antimicrobial-resistant isolates are suggested.


2012 ◽  
Vol 56 (4) ◽  
pp. 459-466 ◽  
Author(s):  
Dariusz Wasyl ◽  
Magdalena Zając ◽  
Derek J. Brown ◽  
Henry Kuronen ◽  
Kim Van Der Zwaluw ◽  
...  

Abstract The molecular epidemiological relationship among isolates of Salmonella enterica serovar (S.) Saintpaul, which was identified in animals, food, and humans in several EU countries, was investigated. Pulsed-field gel electrophoresis (PFGE) revealed a high degree of genetic diversity (82 XbaI PFGE profiles with 42.6% similarity) among 159 S. Saintpaul isolates from animals (n=91), food of animal origin (n=29), and humans (n=36) in 12 European countries during 2005 to 2009. Most frequent profiles (n=12) comprised almost 50% of the tested isolates. Profiles obtained in isolates from a single source within a particular geographical region or particular period of time were indistinguishable or closely related. Turkeys were confirmed as the major reservoir for S. Saintpaul. Indistinguishable PFGE profiles were identified in up to 19 isolates from turkey breeding and fattening flocks and food over the study period. Other animals, including food and pets, may also contribute to S. Saintpaul spread. International trade of animals and food, as well as travelling contributes to the spread of a specific clone to different geographical areas. Although control programmes in breeding turkey flocks, together with improved biosecurity, may interrupt the major transmission routes, it was concluded that S. Saintpaul will continue to represent a potential threat to human health.


2020 ◽  
Author(s):  
Endrias Zewdu Gebremedhin ◽  
Gadisa Hirpa ◽  
Bizunesh Mideksa Borana ◽  
Edilu Jorga Sarba ◽  
Lencho Megersa Marami ◽  
...  

Abstract Background Listeriosis is one of the globally distributed foodborne diseases with the highest fatality rate. Few studies were done on the occurrence of Listeria species from meat at abattoirs, butchers, and restaurants in Ethiopia, and there has been no study conducted at Ambo and Holeta town. The objectives of this study were to isolate and identify Listeria species, assess factors for contamination of meat, and antibiogram of Listeria monocytogenes along the meat chain in Ambo and Holeta towns, Central Ethiopia. Methods 450 meat samples were collected from abattoirs (n = 150), butchers (n = 150) and restaurants (n = 150) for isolation and identification of Listeria species using primary culture and biochemical tests. A questionnaire survey and observational checklist were made to assess the potential risk factors for the occurrence of Listeria species such as factors related to socio-demographic characteristics, knowledge on hygiene and practice of food handlers. Pearson’s Chi-square and logistic regression analyses were used to assess factors contributing for contamination of meat with Listeria species. Kirby Bauer disc diffusion technique was applied to determine the antimicrobial susceptibility profile of Listeria monocytogenes isolates. Results The overall occurrence of Listeria species in both Ambo and Holeta towns was 28.44% (128/450; 95% confidence interval [CI]: 24.32–32.86%). The occurrence of L. monocytogenes was 4.4% (20/450; 95% CI: 2.74–6.78%), L. ivanovii 2.2% (10/450; 95% CI: 1.07–4.04%), L. seeligeri 1.78% (8/450; 95% CI: 0.8–3.47%), L. welshimeri 3.77% (17/450; 95% CI: 2.22–5.98%), L. inoccua 6.22% (28/450; 95% CI: 4.17–8.87%) and L. grayi 10.22% (46/450; 95% CI: 7.58–13.39%). The probability of contamination of meat in butchers and restaurants by the Listeria species were comparatively higher in high altitude (Holeta) than medium altitudes (Ambo) [OR = 4.91; 95% CI: 2.65–9.07%; p < 0.001], in dry than wet season [OR = 8.78; 95% CI: 2.66–28.99%; p < 0.001] and in butchers and restaurant where the employees work ≥ 9 hours per day than those working ≤ 8 hours per day (OR = 3.57; 95% CI:1.74–7.36%; p < 0.001]. Of the 20 Listeria monocytogenes isolates, 16 (80%) were resistant to oxacillin; 14 (70%) were resistant to amikacin and nalidixic acid; 12 (60%) were resistant to chloramphenicol and 11 (55%) were resistant to tetracycline. The L. monocytogenes isolates were 95%, 90% and 85% susceptible to amoxicillin, vancomycin, and clindamycin, respectively. All (100%) Listeria monocytogenes isolates were resistant for two or more drugs. Nineteen (95%) L. monocytogenes isolates were multidrug-resistant. One isolate (5%) had developed resistance to 10 classes of antimicrobial drugs. Conclusions Listeria species are widespread in the study areas. The study towns, season and working hours per day are independent predictors of Listeria species isolation. Multidrug resistance among L. monocytogenes is common. Therefore, regular training for meat handlers, prudent use of drugs, and further serological and molecular studies on Listeria species are important.


2019 ◽  
Vol 37 (2) ◽  
pp. 185
Author(s):  
Wari Pawestri ◽  
Gagak Dhony Satria ◽  
Nisa Hakimah ◽  
Doddi Yudhabuntara

Food products of animal origin which are free from biological and chemical contamination are an absolute requirement of food safety. Antibiotics residues in the food of animal origin is one of the chemical contaminants in food are harmful/hazardous to human health. Tetracycline is an antibiotic that is often used in the fishing industry. The study aims to detect the occurrence of tetracycline residues in tilapia sold in traditional markets in Kota Yogyakarta. The research was conducted with detection test (detect disease). The study used 61 samples of tilapia fish from 16 traditional markets in Kota Yogyakarta. Tilapia meat samples are prepared according to the Association of Official Analytical Chemistry (AOAC). The existence of tetracycline residues in meat can be detected by high performance liquid chromatography (HPLC). Residue analysis in fish meat was conducted at the Department of Pharmacology, Faculty of Veterinary Medicine of Gadjah Mada University using HPLC Shimadzu version 6.1. The results showed that 24 samples of tilapia meat marketed in Kota Yogyakarta was positively contained tetracycline antibiotic residues. A total of 19 samples contained residues above maximum residue limits (MRL). The conclusion of the study is 31% of tilapia marketed in Kota Yogyakarta contains tetracycline residues above MRL. Surveillance of residues in food of animal origin and further research in terms of reducing antibiotic residue in tilapia meat is highly recommended to improve the quality and safety of food of animal origin.


2020 ◽  
Vol 7 ◽  
pp. 31-36
Author(s):  
Dhirendra Niroula ◽  
Jyotsna Shrestha ◽  
Supriya Sharma ◽  
Anjana Singh

Objectives: The study aimed to assess the antibiotic susceptibility profile of Salmonella spp isolated from patients suspected of enteric fever. Methods: This cross-sectional prospective study was carried out from April to June, 2014among 484 patients clinically suspected of enteric fever visiting Bir Hospital, Kathmandu, Nepal. Blood sample collected from each patient was processed for culture in bile broth. Identification of Salmonella spp was done by conventional microbiological techniques including colony characteristics, Gram's staining and biochemical tests. Antibiotic susceptibility testing of identified isolates was done by Kirby-Bauer disk diffusion method following the 2014 CLS I guideline. Results: Out of 484 blood samples, 36 (7.43%) cases showed the growth of Salmonella spp; of which 27 (75%) were Salmonella enterica serovar Typhi (ST) and 9 (25%) were Salmonella enterica Paratyphi A (SPA). Among the Salmonella isolates, 5.55% were multidrug resistant and 41.66% were fluoroquinolone resistant. More than 80% of isolates were sensitive to chloramphenicol, amoxicillin, and cotrimoxazole whereas 58%, 50% and 6% of isolates were sensitive to fluoroquinolone antibiotics i.e. ciprofloxacin, ofloxacin and nalidixic acid respectively. All the isolates were susceptible to ceftazidime. All SPA and 89% of ST were sensitive to azithromycin. Conclusion: Higher percentage of susceptible isolates to chloramphenicol, cotrimoxazole, and amoxicillin suggests the reconsideration of these antibiotics for the treatment of enteric fever. Azithromycin can be considered as drug of choice for the treatment of enteric fever.  


2020 ◽  
Vol 64 (7) ◽  
Author(s):  
Wei Wang ◽  
Li Zhao ◽  
Yujie Hu ◽  
Tania Dottorini ◽  
Séamus Fanning ◽  
...  

ABSTRACT A total of 2,283 Salmonella isolates were recovered from 18,334 samples, including samples from patients with diarrhea, food of animal origin, and pets, across 5 provinces of China. The highest prevalence of Salmonella spp. was detected in chicken meats (39.3%, 486/1,237). Fifteen serogroups and 66 serovars were identified, with Salmonella enterica serovars Typhimurium and Enteritidis being the most dominant. Most (85.5%, 1,952/2,283) isolates exhibited resistance to ≥1 antimicrobial, and 56.4% were multidrug resistant (MDR). A total of 222 isolates harbored extended-spectrum β-lactamases (ESBLs), and 200 of these were of the CTX-M type and were mostly detected in isolates from chicken meat and turtle fecal samples. Overall, eight blaCTX-M genes were identified, with blaCTX-M-65, blaCTX-M-123, blaCTX-M-14, blaCTX-M-79, and blaCTX-M-130 being the most prevalent. In total, 166 of the 222 ESBL-producing isolates had amino acid substitutions in GyrA (S83Y, S83F, D87G, D87N, and D87Y) and ParC (S80I), while the plasmid-mediated quinolone resistance (PMQR)-encoding genes oqxA, oqxB, qepA, qnrB, and qnrS were detected in almost all isolates. Of the 15 sequence types (STs) identified in the 222 ESBLs, ST17, ST11, ST34, and ST26 ranked among the top 5 in number of isolates. Our study revealed considerable serovar diversity and a high prevalence of the co-occurrence of MDR determinants, including CTX-M-type ESBLs, quinolone resistance-determining region (QRDR) mutations, and PMQR genes. This is the first report of CTX-M-130 Salmonella spp. from patients with diarrhea and QRDR mutations from turtle fecal samples. Our study emphasizes the importance of actions, both in health care settings and in the veterinary medicine sector, to control the dissemination of MDR, especially the CTX-M-type ESBL-harboring Salmonella isolates.


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