Exploring the Interplay of the CRISPR-CAS System with Antibiotic Resistance in Staphylococcus aureus: A Poultry Meat Study from Lahore, Pakistan

Staphylococcus aureus is one of the major pathogens responsible for causing food poisoning worldwide. The emergence of antibiotic resistance in this bacterium is influenced by various factors. Among them, bacterial acquired defense systems described as clustered regularly interspaced short palindromic repeats (CRISPR)-cas system might be involved in antibiotic resistance development in bacteria. The current study was designed to assess the prevalence of S. aureus and its antibiotic resistance profile and identify the relationship of the CRISPR-cas system with antimicrobial resistance, followed by phylogenetic analysis. Total samples (n = 188) of poultry meat were collected from the poultry bird market of Lahore, Punjab, Pakistan. We used both phenotypic (antibiotic disc diffusion) and genotypic methods (PCR) to identify multi-drug resistant (MDR) strains of S. aureus. Additionally, the role of the CRISPR-Cas system in the isolated MDR S. aureus was also assessed. In addition, real-time quantitative PCR (qRT-PCR) was used to evaluate the association of the CRISPR-cas system with antimicrobial resistance. All of the S. aureus isolates showed 100% resistance against erythromycin, 97.5% were resistant to tetracycline, and 75% were resistant to methicillin. Eleven isolates were MDR in the current study. The CRISPR system was found in all MDR isolates, and fifteen spacers were identified within the CRISPR locus. Furthermore, MDR S. aureus isolates and the standard strain showed higher expression levels of CRISPR-associated genes. The correlation of said system with MDR isolates points to foreign gene acquisition by horizontal transfer. Current knowledge could be utilized to tackle antibiotic-resistant bacteria, mainly S. aureus.

Therapeutic potential of natural products and antibiotics against bovine mastitis pathogen of cows and buffaloes

The present study aims to evaluate the prevalence and antimicrobial sensitivity of Staphylococcus aureus associated with bovine mastitis to selected antibiotics and plant extracts. In the current study, 140 milk samples were collected from cows and buffaloes. Among the 140 samples, 93 samples were positive for sub-clinical mastitis based on the California Mastitis Test (CMT). Out of the total positive samples, 45 were confirmed for S. aureus on a Mannitol salt agar media. The antimicrobial susceptibility test revealed that 44.82% of the isolates were resistant to cefoxitin (oxacillin) confirming methicillin-resistant S. aureus (MRSA) with a higher percentage (51.61%) in the buffalo than in the cow samples. Furthermore, the PCR assay confirmed the presence of the mecA gene in all the MRSA isolates. Among the seven tested antibiotics, sulfamethoxazole + trimethoprim showed high efficacy (71.1%) against methicillin-susceptible S. aureus isolates (MSSA). Oxytetracycline and sulfamethoxazole + trimethoprim showed 20% efficacy against MRSA followed by enrofloxacin (10%). On the other hand, the tested samples from Pistacia chinensis revealed that the ethyl acetate extract of bark showed a maximum zone of inhibition of 21.3 mm against MSSA and MRSA isolates at 3 000 μg/disc. Moreover, the methanol extract of Cotoneaster microphyllus formed a 12.3 mm and 9.1 mm zone of inhibition against the MSSA and MRSA isolates, respectively.

Nutritional Strategies to Improve Meat Quality and Composition in the Challenging Conditions of Broiler Production: A Review

Poultry meat is becoming one of the most important animal protein sources for human beings in terms of health benefits, cost, and production efficiency. Effective genetic selection and nutritional programs have dramatically increased meat yield and broiler production efficiency. However, modern practices in broiler production result in unfavorable meat quality and body composition due to a diverse range of challenging conditions, including bacterial and parasitic infection, heat stress, and the consumption of mycotoxin and oxidized oils. Numerous studies have demonstrated that appropriate nutritional interventions have improved the meat quality and body composition of broiler chickens. Modulating nutritional composition [e.g., energy and crude protein (CP) levels] and amino acids (AA) levels has altered the meat quality and body composition of broiler chickens. The supplementation of bioactive compounds, such as vitamins, probiotics, prebiotics, exogenous enzymes, plant polyphenol compounds, and organic acids, has improved meat quality and changed the body composition of broiler chickens.

Evaluation of the Prevalence of Staphylococcus aureus in Chicken Fillets and Its Bio-Control Using Different Seaweed Extracts

This study aims to assess the occurrence of Staphylococcus aureus in chicken fillets and to control its growth using various lyophilized seaweed extracts (i.e., Halimeda opuntia (HO), Actinotrichia fragilis, and Turbinaria turbinata) by an agar disk diffusion assay in vitro. Results showed that prevalence of S. aureus in breast and thigh samples reached of 92% and 84%, respectively. Lyophilized HO extract was the only seaweed that showed the antibacterial activity against S aureus with a significant difference at p < 0.05. The minimum inhibitory concentration (MIC) of HO extract was 1.5%, with an inhibition zone of 8.16 ± 0.73 mm. Regarding 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, IC50 was recorded at 55.36 μg/mL, whereas cytotoxic IC50 of the lyophilized HO extract on peripheral blood mononuclear cells (PBMCs) was 33.7 µg/mL; a higher IC50 of HO extracts permits their use as a safe food additive in meat products. Moreover, total phenolic compounds and total flavonoids compounds recorded 20.36 ± 0.092 and 16.59 ± 0.029 mg/mL, respectively. HPLC analyses of phenolic compounds profiles exhibited many bioactive substances and the higher ratio was daidzein with 10.84 ± 0.005 µg/mL and followed by gallic acid with a value of 4.06 ± 0.006 µg/mL. In a challenge study, chicken fillet (CHF) experimentally inoculated with S. aureus (ST) and treated with the lyophilized HO algal extract at 4% and 6% (CHF/ST/HO) showed a complete reduction of S. aureus count on the 6th and 4th days in chicken fillet stored at 4 °C, respectively. Moreover, CHF/ST/HO at 4% and 6% of HO extract enhanced the sensory attributes of grilled un-inoculated chicken fillet. Thus, lyophilized HO extracts are promising antibacterial and antioxidant candidates in the chicken meat industry.

Genetic Characterization and Antimicrobial-Resistant Profiles of Staphylococcus aureus Isolated from Different Food Sources

This study determined the prevalence of Staphylococcus aureus in food of animal origin, investigated its antimicrobial susceptibility profiles and antimicrobial-resistant genes encoding resistance to methicillin (mecA), penicillin (blaZ), and vancomycin (vanA). Two hundred and sixty food samples, including raw retail milk, meat, and meat products, were obtained from local retail shops in Mansoura city, Egypt. The overall prevalence of S. aureus in the total examined food samples was 32.69% (85/260). Methicillin-resistant S. aureus (MRSA) was identified in 11.15% (29/260) of the tested food samples. S. aureus indicated a high resistance to nalidixic acid, penicillin, ampicillin, cefuroxime, trimethoprim/sulfamethoxazole, and azithromycin. The multiple antibiotic resistance (MAR) rate was 89.4% of the total S. aureus isolates, and MARindex ranges from 0.05-0.64. Genotypically, mecA and blaZ genes were identified in a percentage of 34.11% and 82.35%, respectively, while no isolates harbored the vanA gene. The presence of MAR S. aureus particularly, MRSA in food samples, is of great concern and represents a possible threat to the community. Therefore, the study's findings highlight the importance of establishing vigilant food safety practices for food handlers to inhibit the transmission of S. aureus through the food chain to reduce public health risks.

Antimicrobial effects of Cynara scolymus essential oil: In vitro analysis

By benefits of using silicon and vermicompost based biofertilizers and also induction of drought stress for growing more efficient medicinal plants, we investigated such issues on growing Cynara scolymus (C. scolymus), as one of the most significant edible medicinal plants. In this regard, the antimicrobial effects of grown C. scolymus essential oil was investigated against some foodborne pathogens. Different concentrations of silicon and vermicompost with and without drought stress were considered for growing the plant and the extracted essential oils were extracted to examine their antimicrobial effects against different bacterial agents. Using vermicompost and silicon and 50% moisture discharge yielded significant increase in the mean diameter of growth inhibition zone and significant decrease in the minimum inhibitory concentration of tested bacteria (P <  0.05). The highest diameters of the inhibition zones of S. aureus, S. saprophyticus, P. aeruginosa, S. dysenteriae, and S. typhi were found for C. scolymus essential oil treated with 8 mmol silicon and conventional irrigation (14.92 mm), 4 mmol silicon and 50% moisture discharge (15.28 mm), 50% vermicompost and 50% moisture discharge (15.71 mm), 8 mmol silicon and conventional irrigation (17.34 mm) and 25% vermicompost, and 50% moisture discharge (15.48 mm), respectively. Antimicrobial effects of some treatments of C. scolymus were higher than some kinds of referenced antibiotics such as erythromycin. These findings could be used for the production of antibiotic drugs for specific purposes against certain bacteria.

Antimicrobial effects of Arctium lappa against infectious bacteria: Experimental in vitro analysis

Arctium lappa (A. lappa) is one of the most significant edible medicinal plants with high antibacterial effects, in which it could be supposed to grow with more beneficial effects under administration by salicylic acid and chitosan based biofertilizers. Accordingly, the effects of salicylic acid, chitosan, and 50% moisture discharge were investigated in this work to see the antimicrobial treatments of some foodborne pathogens effects by A. lappa. To this aim, plants were cultivated based on different concentrations of salicylic acid and chitosan with/without drought stress, in which their extracted essential oils were examined for showing the antimicrobial effect against different bacterial agents. The results indicated that the salicylic acid and chitosan administrated A. lappa could work with improved inhibitory functions. Comparing with referenced antibiotics showed even higher antimicrobial effects of A. lappa against the targeted bacterial agents, in which the species with 14 mmol of salicylic acid and 2 g/l of chitosan was a distinguished one for approaching the purpose. Consequently, the achievements of this work could be further investigated for producing novel antibiotic drug agents.

The Prevalence and Molecular Biology of Staphylococcus aureus Isolated from Healthy and Diseased Equine Eyes in Egypt

This work aimed to characterize S. aureus isolates from the eyes of healthy and clinically affected equines in the Kafrelsheikh Governorate, Egypt. A total of 110 animals were examined for the presence of S. aureus, which was isolated from 33 animals with ophthalmic lesions and 77 healthy animals. We also investigated the antimicrobial resistance profile, oxacillin resistance mechanism, and the major virulence factors implicated in many studies of the ocular pathology of pathogenic S. aureus. The association between S. aureus eye infections and potential risk factors was also investigated. The frequency of S. aureus isolates from clinically affected equine eyes was significantly higher than in clinically healthy equids. A significant association was found between the frequency of S. aureus isolation from clinically affected equine eyes and risk factors including age and season but not with sex or breed factors. Antimicrobial resistance to common antibiotics used to treat equine eyes was also tested. Overall, the isolates showed the highest sensitivity to sulfamethoxazole (100%) and the highest resistance to cephalosporin (90.67%) and oxacillin (90.48%). PCR was used to demonstrate that mecA was present in 100% of oxacillin- and β-lactam-resistant S. aureus strains. The virulence factor genes Spa (x region), nuc, and hlg were identified in 62.5%, 100%, and 56%, of isolates, respectively, from clinically affected equines eyes. The severity of the eye lesions increased in the presence of γ-toxin-positive S. aureus. The phylogenetic tree of the Spa (x region) gene indicated a relationship with human reference strains isolated from Egypt as well as isolates from equines in Iran and Japan. This study provides insight into the prevalence, potential risk factors, clinical pictures, zoonotic potential, antimicrobial resistance, and β-lactam resistance mechanism of S. aureus strains that cause eye infection in equines from Egypt.

Staphylococcus aureus in poultry, with special emphasis on methicillin-resistant strain infection: A comprehensive review from one health perspective

Staphylococcus aureus is a Gram-positive coccus normally present on the skin and internal organs of animals, birds, and humans. Under certain conditions, S. aureus could produce septicemia and affection of the skin, joints, and heart, as well as sepsis and death. The pathogenicity of S. aureus is associated with the presence of some virulent surface proteins and the production of some virulent toxins and enzymes. This pathogen is considered one of the most important and worldwide foodborne causes as it is incriminated in most cases of food poisoning. The hazardous use of antibiotics in the veterinary field leads to the development of multidrug-resistant S. aureus strains that can be transmitted to humans. The incidence of methicillin-resistant S. aureus (MRSA) strains has increased globally. These resistant strains have been detected in live animals, poultry, and humans. In addition, retail animal products, especially those of avian origin, are considered the main source of MRSA strains that can be easily transmitted to humans. MRSA infection is regarded as nosocomial or occupational. Humans get infected with MRSA strains through improper handling or preparation of contaminated animals or poultry carcasses or improper cooking with contaminated meat. Live birds also can transmit MRSA to close-contact workers in poultry farms. Transmission of MRSA infection in hospitals is from an infected individual to a healthy one. Prevention and control of MRSA are based on the application of hygienic measures in farms as well as proper processing, handling, and cooking of retail poultry products. The cooperation between veterinary and human practitioners is a must to avoid the possibility of zoonotic transmission. Accordingly, this review focused on the sources and transmission of MRSA infection, virulence and resistance factors, incidence and prevalence in poultry and different products, antibiotic resistance, and prevention and control strategies.

Antimicrobial-resistant foodborne pathogens in the Middle East: a systematic review

Foodborne pathogens are known as significant public health hazards worldwide, particularly in the Middle East region. Antimicrobial resistance (AMR) among foodborne pathogens becomes one of the top challenges for the environment, public health, and food safety sectors. However, less is known about antimicrobial-resistant foodborne pathogens in the Middle East region. Possibly because of the lack of surveillance, documentation, and reporting. This review focuses on the current status of antimicrobial resistance profiling among foodborne pathogens in the Middle East. Therefore, PubMed and other relevant databases were searched following PRISMA guidelines. Subject heading and texts were searched for "antimicrobial resistances," "foodborne," and "Middle East" to identify observational studies on AMR foodborne pathogens published during the last 10 years (2011 to 2020). Article retrieval and screening were done using a structured search string and strict inclusion/exclusion criteria. Median and interquartile ranges of percent resistance were calculated for each antibiotic-bacterium combination. A total of 249 articles were included in the final analysis from ten countries, where only five countries had more than 85% of the included articles. The most commonly reported pathogens were Escherichia coli, Salmonella spp. Staphylococcus aureus, and Listeria spp. An apparent rise in drug resistance among foodborne pathogens was recorded particularly against amoxicillin-clavulanic acid, ampicillin, nalidixic acid, streptomycin, and tetracycline that are commonly prescribed in most countries in the Middle East. Besides, there is a lack of standardization and quality control for microbiological identification and susceptibility testing methods in many of the Middle East countries.

A survey of prevalence and phenotypic and genotypic assessment of antibiotic resistance in Staphylococcus aureus bacteria isolated from ready-to-eat food samples collected from Tehran Province, Iran

BACKGROUND

Resistant Staphylococcus aureus (S. aureus) bacteria are considered among the major causes of foodborne diseases. This survey aims to assess genotypic and phenotypic profiles of antibiotic resistance in S. aureus bacteria isolated from ready-to-eat food samples.

METHODS

According to the previously reported prevalence of S. aureus in ready-to-eat food samples, a total of 415 ready-to-eat food samples were collected from Tehran province, Iran. S. aureus bacteria were identified using culture and biochemical tests. Besides, the phenotypic antibiotic resistance profile was determined by disk diffusion. In addition, the genotypic pattern of antibiotic resistance was determined using the PCR.

RESULTS

A total of 64 out of 415 (15.42%) ready-to-eat food samples were contaminated with S. aureus. Grilled mushrooms and salad olivieh harbored the highest contamination rate of (30%), while salami samples harbored the lowest contamination rate of 3.33%. In addition, S. aureus bacteria harbored the highest prevalence of resistance to penicillin (85.93%), tetracycline (85.93%), gentamicin (73.43%), erythromycin (53.12%), trimethoprim-sulfamethoxazole (51.56%), and ciprofloxacin (50%). However, all isolates were resistant to at least four antibiotic agents. Accordingly, the prevalence of tetK (70.31%), blaZ (64.06%), aacA-D (57.81%), gyrA (50%), and ermA (39.06%) was higher than that of other detected antibiotic resistance genes. Besides, AacA-D + blaZ (48.43%), tetK + blaZ (46.87%), aacA-D + tetK (39.06%), aacA-D + gyrA (20.31%), and ermA + blaZ (20.31%) were the most frequently identified combined genotypic patterns of antibiotic resistance.

CONCLUSION

Ready-to-eat food samples may be sources of resistant S. aureus, which pose a hygienic threat in case of their consumption. However, further investigations are required to identify additional epidemiological features of S. aureus in ready-to-eat foods.

Prevalence and Characteristics of Staphylococcus aureus Associated with Meat and Meat Products in African Countries: A Review

Antimicrobial resistance has been increasing globally, which negatively affects food safety, veterinary, and human medicine. Ineffective antibiotics may cause treatment failure, which results in prolonged hospitalisation, increased mortality, and consequently, increased health care costs. Staphylococcus aureus causes a diverse range of infections including septicaemia and endocarditis. However, in food, it mainly causes food poisoning by the production of enterotoxins. With the discovery of methicillin-resistant S. aureus strains that have a separate reservoir in livestock animals, which were termed as livestock-associated methicillin-resistant S. aureus (LA-MRSA) in 2005, it became clear that animals may pose another health risk. Though LA-MRSA is mainly transferred by direct contact, food transmission cannot be excluded. While the current strains are not very pathogenic, mitigation is advisable, as they may acquire new virulence genes, becoming more pathogenic, and may transfer their resistance genes. Control of LA-MRSA poses significant problems, and only Norway has an active mitigation strategy. There is limited information about LA-MRSA, MRSA in general, and other S. aureus infections from African countries. In this review, we discuss the prevalence and characteristics of antimicrobial susceptible and resistant S. aureus (with a focus on MRSA) from meat and meat products in African countries and compare it to the situation in the rest of the world.

Molecular Characterization of Bacteria, Detection of Enterotoxin Genes, and Screening of Antibiotic Susceptibility Patterns in Traditionally Processed Meat Products of Sikkim, India

The lesser-known traditionally processed meat products such as beef kargyong, pork kargyong, satchu, and khyopeh are popular food items in the Himalayan state of Sikkim in India. The present study aimed to assess the microbiological safety of traditional meat products by identifying the potential spoilage or pathogenic bacteria, detecting the enterotoxins, and screening the antibiotic susceptibility patterns. The pH and moisture contents of the meat products varied from 5.3 to 5.9 and from 1.5 to 18%, respectively. The microbial loads of aerobic bacteria were 105 to 107 cfu/g, Staphylococcus 103 to 106 cfu/g, Bacillus 104 to 106 cfu/g, and total coliform 102 to 107 cfu/g, respectively. Based on 16S rRNA gene sequencing, the bacterial species isolated from traditionally processed meat products were Staphylococcus piscifermentans, Citrobacter freundii, Enterococcus faecalis, Salmonella enterica, Staphylococcus aureus, Citrobacter werkmanii, Klebsiella pneumoniae, Macrococcus caseolyticus, Klebsiella aerogenes, Staphylococcus saprophyticus, Pseudocitrobacter anthropi, Citrobacter europaeus, Shigella sonnei, Escherichia fergusonii, Klebsiella grimontii, Burkholderia cepacia, and Bacillus cereus. The enzyme-linked immunosorbent assay (ELISA) tests detected Salmonella spp. and enterotoxins produced by B. cereus well as Staphylococcus in a few tested samples. However, the PCR method did not detect the virulence genes of B. cereus and Salmonella in the isolates. Virulence gene (sea) was detected in S. piscifermentans BSLST44 and S. piscifermentans BULST54 isolated from beef kargyong and in S. aureus PSST53 isolated from pork kargyong. No enterotoxins were detected in khyopeh samples. The antibiotic sensitivity test showed that all bacterial strains were susceptible toward gentamicin, cotrimoxazole, norfloxacin, and trimethoprim. Gram-positive bacteria showed 100% sensitivity against clindamycin and erythromycin; however, 50% of the resistance pattern was observed against oxacillin followed by penicillin (33%) and ampicillin (27%).

Phenotypic and Genotypic Assessment of Antibiotic Resistance of Staphylococcus aureus Bacteria Isolated from Retail Meat

BACKGROUND

Resistant Staphylococcus aureus (S. aureus) bacteria are determined to be one of the main causes of foodborne diseases.

PURPOSE

This survey was done to assess the genotypic and phenotypic profiles of antibiotic resistance of S. aureus bacteria isolated from retail meat.

METHODS

Four-hundred and eighty-five retail meat samples were collected and examined. S. aureus bacteria were identified using culture and biochemical tests. The phenotypic profile of antibiotic resistance was examined using the disk diffusion method. The genotypic pattern of antibiotic resistance was determined using the polymerase chain reaction.

RESULTS

Forty-eight out of 485 (9.89%) raw retail meat samples were contaminated with S. aureus. Raw retail buffalo meat (16%) had the highest incidence of S. aureus, while raw camel meat (4%) had the lowest. S. aureus bacteria exhibited the uppermost incidence of resistance toward tetracycline (79.16%), penicillin (72.91%), gentamicin (60.41%), and doxycycline (41.666%). The incidence of resistance toward chloramphenicol (8.33%), levofloxacin (22.91%), rifampin (22.91%), and azithromycin (25%) was lower than other examined antibiotics. The most routinely detected antibiotic resistance genes were blaZ (58.33%), tetK (52.08%), aacA-D (33.33%), and ermA (27.08%). Cat1 (4.16%), rpoB (10.41%), msrA (12.50%), grlA (12.50%), linA (14.58%), and dfrA1 (16.66%) had the lower incidence rate.

CONCLUSION

Raw meat of animals may be sources of resistant S. aureus which pose a hygienic threat about the consumption of raw meat. Nevertheless, further investigations are essential to understand supplementary epidemiological features of S. aureus in retail meat.

Effects of probiotic, cinnamon, and synbiotic supplementation on glycemic control and antioxidant status in people with type 2 diabetes; a randomized, double-blind, placebo-controlled study

Purpose

The aim of this study was to investigate the effect of probiotic bacteria of Lactobacillus acidophilus, cinnamon powder and their combinations on the glycemic and antioxidant indices in patients with type 2 diabetes.

Methods

A total of 136 patients randomized with type 2 diabetes entered the study and were randomly divided into four groups who were matched for age and gender. Thereafter, alongside their routine pharmacotherapy, each group followed one of the following diets: Group A: Lactobacillus acidophilus 10⁸ cfu and 0.5 g of powdered cinnamon (synbiotic). Group B: Lactobacillus acidophilus (probiotic), Group C: powdered cinnamon. Group D: rice flour powder as placebo. At the beginning and end of the intervention, fasting blood sugar (FBS), HbA1c, advance glycation end products (AGE), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and antioxidant enzymes of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were measured.

Results

Following 3 months of treatment, the mean FBS level was decreased significantly in probiotic, cinnamon, and synbiotic supplementation groups compared with control (P < 0.01). FBS levels in probiotic, cinnamon, and synbiotic groups were significantly decreased compared with the control group (P = 0.001, P = 0.063 and P = 0.001, respectively). The mean HbA1C in probiotic, cinnamon, and synbiotic groups were also decreased (P = 0.001, P = 0.001 and P = 0.04, respectively). The mean AGE in synbiotic group was significantly decreased (P = 0.037). Probiotic, cinnamon and synbiotic all could improve antioxidant enzyme activity modestly. However, the most significant effect was seen in probiotic group.

Conclusions

According to the current results, the use of probiotic supplements (individually or in combination with cinnamon) leads to a reduction in blood glucose and an increase in antioxidant enzymes in people with type 2 diabetes.

Virulence factors and antibiotic resistance properties of the Staphylococcus epidermidis strains isolated from hospital infections in Ahvaz, Iran

BACKGROUND

Resistant Staphylococcus epidermidis strains are considered to be one of the major causes of human clinical infections in hospitals. The present investigation was done to study the pattern of antibiotic resistance and the prevalence of virulence and antibiotic resistance genes amongst the S. epidermidis strains isolated from human hospital infections.

METHODS

One hundred hospital infectious samples were collected and S. epidermidis strains were identified using culture and biochemical tests. Isolated strains were subjected to disk diffusion and PCR.

RESULTS

Forty-six out of 100 hospital infectious samples (46%) were positive for S. epidermidis. S. epidermidis strains harbored the highest prevalence of resistance against penicillin (95.65%), tetracycline (91.30%), erythromycin (82.60%), cefazolin (78.26%), and trimethoprim-sulfamethoxazole (73.91%). All S. epidermidis strains had resistance against at least three different types of antibiotics, while the prevalence of resistance against more than seven types of antibiotics was 17.39%. AacA-D (69.56%), tetK (56.52%), mecA (45.65%), msrA (39.13%), and tetM (39.13%) were most commonly detected antibiotic resistance genes. The prevalence of vatC (4.34%), ermA (8.69%), vatA (8.69%), vatB (13.04%), ermC (13.04%), and linA (10.86%) were lower than other detected antibiotic resistance genes. ClfA (32.60%), agrIII (17.39%), and etB (13.04%) were the most commonly detected virulence factors.

CONCLUSIONS

The presence of virulent and multi-drug resistance S. epidermidis strains showed an important public health issue in hospitals.

Methicillin-Resistant Staphylococcus aureus in Seafood: Prevalence, Laboratory Detection, Clonal Nature, and Control in Seafood Chain

Methicillin-resistant Staphylococcus aureus (MRSA), a versatile pathogen bearing multiple virulence determinants, is increasingly being detected in various food-producing animals, including fish. In addition, it is a potential food poisoning agent. MRSA is not an inherent microbiota of fish; its presence is attributed to pre- or postharvest contamination through fish handlers, water, ice, and processing equipment. Several reviews have been written on MRSA in clinical as well as the food animal-producing sector, but information specific to MRSA in seafood is scant. This review puts forth insights on MRSA detection in seafood, antibiotic resistance, diversity of clones in seafood, and possible control measures in seafood production chain. Emphasis has been given on assessing the variations in the protocols employed for isolation and identification in different food matrices and lay the foundation for researchers to develop optimized procedure.

Prevalence and phenotypic pattern of antibiotic resistance of Acinetobacter baumannii isolated from different types of raw meat samples in Isfahan, Iran

Resistant Acinetobacter baumannii isolates are not only known as opportunistic nosocomial bacteria but may also be regarded as emerging bacterial contaminants in foods of animal origins. The present investigation was done to assess the prevalence and antibiotic resistance pattern of A. baumannii isolated from different types of raw meat samples. One hundred and ninety-four raw meat samples were collected and cultured for A. baumannii isolates. Culture-positive bacteria were also approved using the loop-mediated isothermal amplification (LAMP) technique. The disc diffusion method was used for antibiotic susceptibility testing. Out of 194 raw meat samples, 39 (20.10%) were positive for A. baumannii isolates. Ovine raw meat was the most commonly contaminated samples (32.14%). All of the culture-positive A. baumannii isolates were also approved using the LAMP assay. A. baumannii isolates harboured the highest prevalence of resistance against gentamicin (87.17%), tetracycline (79.48%), erythromycin (74.35%), azithromycin (66.66%), ciprofloxacin (58.97%), trimethoprim/sulphamethoxazole (56.41%) and rifampin (51.28%). The lowest prevalence of resistance was found against imipenem (17.94%) and chloramphenicol (28.20%). Raw bovine, ovine, caprine, camel and poultry meat samples were considered as the important sources of isolates resistant to some of the categories of antimicrobials used to treat infections caused by A. baumannii. Further studies are required to find the exact role of resistant A. baumannii isolates in the dissemination of antibiotic resistance to human population.

Phenotypic and genotypic characterization of antibiotic resistance in the methicillin-resistant Staphylococcus aureus strains isolated from hospital cockroaches

Background

Cockroaches are one of the most important and frequent insects responsible for harboring, transmission and dissemination of human pathogens in the hospital environment. The present research was done to study the phenotypic and genotypic characterization of antibiotic resistance in the Methicillin-resistant Staphylococcus aureus strains isolated from hospital cockroaches.

Methods

Five-hundred and thirty Periplanets americana and Blattella germanica cockroaches were collected and their gut content and external washing samples were subjected to bacterial isolation. MRSA strains were subjected to disk diffusion and PCR amplification of antibiotic resistance genes.

Results

Prevalence of MRSA strains in P. americana and B. germanica cockroaches were 52.77 and 43.33%, respectively. External washing samples of P. americana cockroaches had the highest prevalence of MRSA strains (59.57%). MRSA isolates of external washing samples harbored the highest prevalence of resistance against penicillin (100%), ceftaroline (100%), tetracycline (100%), gentamicin (83.33%) and trimethoprim-sulfamethoxazole (80.55%). MRSA strains isolated from gut content samples harbored the highest prevalence of resistance against penicillin (100%), ceftaroline (100%), tetracycline (100%), trimethoprim-sulfamethoxazole (80%) and gentamicin (73.33%). BlaZ, aacA-D, tetK, msrA, dfrA, ermA, gyrA, grlA and rpoB were the most commonly detected antibiotic resistance genes amongst the MRSA strains.

Conclusions

The present investigation is the first report of the phenotypic and genotypic evaluation of antibiotic resistance in the MRSA strains isolated from P. americana and B. germanica hospital cockroaches. Hospital cockroaches are considered as a potential mechanical vector for MRSA strains.

Virulent methicillin resistant Staphylococcus aureus (MRSA) in street vended foods

Street foods are one of the important sources of foodborne infections and Staphylococcus aureus is an important infectious agent transmitted through various sources including street foods. The methicillin-resistant S. aureus (MRSA) are of public health significance, hence the study was taken to assess the street foods as a source of MRSA, for which 430 street vended foods of animal origin (meat, milk, eggs and their products) and associated environmental samples were processed for isolation and characterization. A total of 52 (12.1%) S. aureus were isolated and resistant was observed to oxacillin (36.5%), cefoxitin (25%) and penicillin G (82.7%) by disc diffusion test. On genotypic screening, mecA and blaZ have detected in 17.3% and 69.2% isolates, respectively. The virulence typing identified nuc, coa, clfA, spA, FnbA and enterotoxin A (sea) genes in 100%, 96.2%, 30.8%, 55.8, 50% and 7.7% isolates, respectively. Genetic diversity among the isolates was observed by enterobacterial repetitive intergenic consensus PCR with a D value of 0.77. The presence of virulent MRSA in street vended foods trigger the public health concern and emphasis to educate the consumers and street food vendors about quality and safety of such foods.

Antibacterial effect of ozonated water against methicillin-resistant Staphylococcus aureus contaminating chicken meat in Wasit Province, Iraq

BACKGROUND AND AIM

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most recognized "superbugs" and a common cause of community-associated and nosocomial infections; furthermore, when chicken meat is considered a good growth medium for S. aureus to make a plausible vehicle to propagate MRSA, then this study was conducted to evaluate the efficiency of ozonated water (0.5 ppm) in the elimination or reduction of MRSA contaminating fresh and frozen chicken meat sold in local markets in the Wasit Province.

MATERIALS AND METHODS

A total of 72 samples of fresh and frozen chicken meat were randomly collected from dissimilar native markets: Fresh chicken meat (n=32) and frozen chicken meat (n=40). Isolation and identification of MRSA isolates were conducted using standard bacteriological, biochemical, RapID™ Staph Plus System (Remel, R8311009), and latex agglutination tests such as Dry SPOT Staphytect Plus (Oxoid, DR0100M) and PBP2' Test Kit (Oxoid, DR0900A). The generation of ozone (O3) was carried out using O3 generator (A2Z/AQUA-6, USA), and its concentration (ppm) in water was determined using CHE-Mets®-Kit, USA.

RESULTS

A total of 39 (54.2%) of 72 fresh and frozen chicken meat were positive for S. aureus; of those 39 positive samples, 13 (33.3%) were identified as MRSA. The antibiotic sensitivity test results revealed that all MRSA isolates had multiple resistance to at least four antimicrobial agents for which these isolates had 12 antibiotic resistance patterns. Results of O3 treatment in MRSA isolate contaminating 13 of both fresh and frozen chicken meat samples showed that, after treatment with ozonated water (0.5 ppm/4°C), the overall negative samples were 23.1% and 69.2% for 30 and 45 min, respectively. The decrease in the percentage of positive samples was very significant from a public health perspective. Furthermore, the antimicrobial efficacy of ozonated water (0.5 ppm) on the reduction of the MRSA count (log10 colony-forming units [CFU]/ml) was assessed in four positive samples of fresh and frozen chicken meat, and the results revealed that, after treatments, the overall reduction was 2-4 log10 (CFU/ml) after 45 min. This reduction is highly significant from a public health perspective.

CONCLUSION

From the data obtained from this study, it can be concluded that fresh and frozen chicken meat sold in the different markets of Wasit Province was highly contaminated by S. aureus during the study period with a total prevalence of 54.2%; among those, 33.3% were recognized as MRSA. Under the conditions described in the present study, O3 at the concentration of 0.5 ppm is highly effective in reducing the number of MRSA-positive samples and the number decreased with increased exposure time to ozonated water at the same concentration. These findings indicated that O3 treatment might constitute the basis for an alternative method to reduce meat contamination with foodborne pathogens such as MRSA.

Genotyping and distribution of putative virulence factors and antibiotic resistance genes of Acinetobacter baumannii strains isolated from raw meat

Background

Acinetobacter baumannii strains with multiple antimicrobial resistance are primarily known as opportunistic nosocomial bacteria but they may also be regarded as emerging bacterial contaminants of food samples of animal origin. Here we aimed to study the molecular characteristics of the A. baumanni strains isolated from raw meat samples.

Methods

A total of 22 A. baumanni strains were isolated from 126 animal meat samples and were genotyped by ERIC-PCR method and by PCR detection of their virulence and antimicrobial resistance determinants. A. baumannii strains with 80% and more similarities were considered as one cluster.

Results

Sixteen different genetic clusters were found amongst the 22 A. baumanni strains. Of the 22 strains, 12 (54.54%) had similar genetic cluster. A. baumannii strains exhibited the highest percentage of resistance against tetracycline (90.90%), trimethoprim (59.09%), cotrimoxazole (54.54%) and gentamicin (50.00%). TetA (81.81%), tetB (72.72%), dfrA1 (63.63%), aac(3)-IV (63.63%), sul1 (63.63%) and aadA1 (45.45%) were the most commonly detected antibiotic resistance genes. FimH (81.81%), afa/draBC (63.63%), csgA (63.63%), cnf1 (59.09%), cnf2 (54.54%) and iutA (50.00%) were the most commonly detected virulence factors. A. baumannii strains isolated from the chicken meat samples had the highest similarities in the genetic cluster.

Conclusions

A. baumannii strains with similar genetic cluster (ERIC-Type) had the same prevalence of antibiotic resistance, antibiotic resistance genes and virulence factors. Genetic cluster of the A. baumannii strains is the main factor affected the similarities in the genotypic and phenotypic properties of the A. baumannii strains.

Prevalence, identification of virulence factors, O-serogroups and antibiotic resistance properties of Shiga-toxin producing Escherichia coli strains isolated from raw milk and traditional dairy products

Background

Shiga-toxigenic Escherichia coli strains are one of the most important foodborne bacteria with an emergence of antibiotic resistance. Foodborne STEC strains are mainly associated with presence of certain virulence factors and O-seogroups. The present investigation was done to study the distribution of virulence factors, O-serogroups and antibiotic resistance properties of Shiga-toxigenic Escherichia coli isolated from milk and dairy products.

Methods

Six-hundred samples were randomly collected and immediately transferred to laboratory. All samples were cultured and E. coli strains were isolated. STEC strains were identified based on the presence of putative virulence factors and subtypes. STEC isolates were subjected to multiplex PCR and disk diffusion methods.

Results

One-hundred and eighty-one out of 600 samples (30.16%) harbored E. coli. Prevalence of STEC strains was 10.66%. O157 (43.75%) and O26 (37.50%) were the most frequently identified serogroups. Aac(3)-IV (100%), CITM (96.87%) and tetA (76.56%) were the most commonly detected antibiotic resistance genes. STEC strains had the highest prevalence of resistance against ampicillin (100%), gentamicin (100%) and tetracycline (96.87%).

Conclusions

Kashk and dough were negative for presence of E. coli strains. High prevalence of resistant-O157 strains and simultaneous presence of multiple virulence factors pose an important public health problem regarding the consumption of raw milk and dairy products.

Uropathogenic Escherichia coli in the Urine Samples of Iranian Dogs: Antimicrobial Resistance Pattern and Distribution of Antibiotic Resistance Genes

Resistant uropathogenic Escherichia coli is the most common cause of urinary tract infections in dogs. The present research was done to study the prevalence rate and antimicrobial resistance properties of UPEC strains isolated from healthy dogs and those which suffered from UTIs. Four-hundred and fifty urine samples were collected and cultured. E. coli-positive strains were subjected to disk diffusion and PCR methods. Two-hundred out of 450 urine samples (44.4%) were positive for E. coli. Prevalence of E. coli in healthy and infected dogs was 28% and 65%, respectively. Female had the higher prevalence of E. coli (P = 0.039). Marked seasonality was also observed (P = 0.024). UPEC strains had the highest levels of resistance against gentamicin (95%), ampicillin (85%), amikacin (70%), amoxicillin (65%), and sulfamethoxazole-trimethoprim (65%). We found that 21.50% of UPEC strains had simultaneously resistance against more than 10 antibiotics. Aac(3)-IV (77%), CITM (52.5%), tetA (46.5%), and sul1 (40%) were the most commonly detected antibiotic resistance genes. Findings showed considerable levels of antimicrobial resistance among UPEC strains of Iranian dogs. Rapid identification of infected dogs and their treatment based on the results of disk diffusion can control the risk of UPEC strains.

Phenotypic and genotypic characterization of antibiotic resistance of methicillin-resistant Staphylococcus aureus isolated from hospital food

BACKGROUND

Pathogenic biotypes of the Methicillin-resistant Staphylococcus aureus (MRSA) strains are considered to be one of the major cause of food-borne diseases in hospitals. The present investigation was done to study the pattern of antibiotic resistance and prevalence of antibiotic resistance genes of different biotypes of the MRSA strains isolated from various types of hospital food samples.

METHODS

Four-hundred and eighty-five raw and cooked hospital food samples were cultured and MRSA strains were identified using the oxacillin and cefoxitin disk diffusion tests and mecA-based PCR amplification. Isolated strains were subjected to biotyping and their antibiotic resistance patterns were analyzed using the disk diffusion and PCR methods.

RESULTS

Prevalence of S. aureus and MRSA were 9.69 and 7.62%, respectively. Meat and chicken barbecues had the highest prevalence of MRSA. Prevalence of bovine, ovine, poultry and human-based biotypes in the MRSA strains were 8.10, 8.10, 32.43 and 48.64%, respectively. All of the MRSA strains recovered from soup, salad and rice samples were related to human-based biotypes. MRSA strains harbored the highest prevalence of resistance against penicillin (100%), ceftaroline (100%), tetracycline (100%), erythromycin (89.18%) and trimethoprim-sulfamethoxazole (83.78%). TetK (72.97%), ermA (72.97%), msrA (64.86%) and aacA-D (62.16%) were the most commonly detected antibiotic resistance genes.

CONCLUSIONS

Pattern of antibiotic resistance and also distribution of antibiotic resistance genes were related to the biotype of MRSA strains. Presence of multi-drug resistance and also simultaneous presence of several antibiotic resistance genes in some MRSA isolates showed an important public health issue Further researches are required to found additional epidemiological aspects of the MRSA strains in hospital food samples.

Genetic characterisation of antimicrobial resistance and virulence genes in <i>Staphylococcus aureus</i> isolated from commercial broiler chickens in the Durban metropolitan area, South Africa

Antimicrobial resistance of Staphylococcus aureus in human and veterinary medicine is a serious worldwide problem. The aim of this study was to investigate the prevalence of S. aureus in commercial broiler chickens as well as to establish antimicrobial susceptibility and the distribution of genetic determinants conferring resistance and virulence. One hundred and ninety-four samples were aseptically collected from broiler chicken slaughterhouses and retail outlets around the Durban metropolitan area in South Africa. Microbiological and molecular methods were used to detect the presence of S. aureus as well as its resistance- and virulence-associated genes. Polymerase chain reaction (PCR) was used to confirm the presence of S. aureus by amplifying the nuc gene. Approximately 54% of 194 samples were positive for S. aureus. The disc diffusion technique was used to investigate antimicrobial susceptibility profiles of the S. aureus isolates to a battery of 10 antimicrobial agents, namely ampicillin, chloramphenicol, gentamicin, erythromycin, cefoxitin, kanamycin, streptomycin, tetracycline, vancomycin and trimethoprim. The results demonstrated that S. aureus isolates of abattoir origin had a high level (79.4%) of resistance to tetracycline, followed by ampicillin, vancomycin, cefoxitin, trimethoprim, erythromycin and streptomycin with resistance rates of 65.1%, 61.9%, 60.3%, 58.7%, 57.1% and 46.0%, respectively. Staphylococcus aureus isolates of retail origin exhibited higher antimicrobial resistance prevalence rates than those of abattoir origin. Tetracycline had the highest resistance rate (100%), followed by cefoxitin (91.7%), erythromycin (83.3%), streptomycin (83.3%) and kanamycin (66.7%). All isolates were resistant to two or more antimicrobial agents. Out of the four virulence genes that were screened, only two were detected (coagulase and protein A); however, their prevalence rates were very low. All antimicrobial resistance genes screened were detected (mecA, BlaZ and tetK), although their prevalence did not correspond with antimicrobial susceptibility testing.

Prevalence of the Antibiotic Resistance Genes in Coagulase-Positive-and Negative-Staphylococcus in Chicken Meat Retailed to Consumers

The use of antibiotics in farm management (growing crops and raising animals) has become a major area of concern. Its implications is the consequent emergence of antibiotic resistant bacteria (ARB) and accordingly their access into the human food chain with passage of antibiotic resistance genes (ARG) to the normal human intestinal microbiota and hence to other pathogenic bacteria causative human disease. Therefore, we pursued in this study to unravel the frequency and the quinolone resistance determining region, mecA and cfr genes of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), methicillin-resistant coagulase-negative staphylococci (MRCNS) and methicillin-susceptible coagulase-negative staphylococci (MSCNS) isolated from the retail trade of ready-to-eat raw chicken meat samples collected during 1 year and sold across the Great Cairo area. The 50 Staphylococcus isolated from retail raw chicken meat were analyzed for their antibiotic resistance phenotypic profile on 12 antibiotics (penicillin, oxacillin, methicillin, ampicillin-sulbactam, erythromycin, tetracycline, clindamycin, gentamicin, ciprofloxacin, chloramphenicol, sulfamethoxazole-trimethoprim, and vancomycin) and their endorsement of the quinolone resistance determining region, mecA and cfr genes. The isolation results revealed 50 isolates, CPS (14) and CNS (36), representing ten species (S. aureus, S. hyicus, S. epidermedius, S. lugdunensis, S. haemolyticus, S. hominus, S. schleiferi, S. cohnii, S. intermedius, and S. lentus). Twenty seven isolates were methicillin-resistant. Out of the characterized 50 staphylococcal isolates, three were MRSA but only 2/3 carried the mecA gene. The ARG that bestows resistance to quinolones, β-lactams, macrolides, lincosamides, and streptogramin B [MLS(_B)] in MRSA and MR-CNS were perceived. According to the available literature, the present investigation was a unique endeavor into the identification of the quinolone-resistance-determining-regions, the identification of MRSA and MR-CNS from retail chicken meat in Egypt. In addition, these isolates might indicate the promulgation of methicillin, oxacillin and vancomycin resistance in the community and imply food safety hazards.