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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.

Brucellosis is a zoonotic disease which is characterized by reduced fertility and abortion in several species of animals, as well as humans. Camel brucellosis is caused by Brucella abortus and Brucella melitensis. To overcome the limitations posed by other techniques such as culture and serology, a sensitive technique (PCR) was employed for the detection of brucellosis in 123 camels. Findings from this PCR study indicated a total of 11.38% of blood samples as positive for Brucella spp. and 13.01% of the lymph node samples were positive for Brucella spp. In this study, 5 out of 123 (4.065%) and 3 out of 123 (2.439%) camel blood samples were positive for B. abortus and B. melitensis, respectively. Also, 4 out of 123 (3.252%) and 2 out of 123 (1.626%) camel lymph node samples were positive for B. abortus and B. melitensis, respectively. Young camels were the most commonly infected age group, while adult camels were the less often infected age group. Also, higher prevalence of brucellosis was observed in female camels. These results have indicated that PCR is a sensitive technique which could be used as a confi rmatory test for the detection of brucellosis in live camels, at the same time with the lowest risk of infection of laboratory personnel. The obtained results suggest that control and eradication programs for Brucella spp. infection seem to be necessary in camels. Our fi ndings support the power of PCR test for Brucella spp. detection in the blood and lymph node samples and it could be easily used for routine diagnosis.

Between September 2006 and September 2007, 236 samples of raw (n=140), pasteurized (n=48) and UHT (n=48) milk were collected from supermarkets and from bulk milk tanks of eight dairy plants in the cities of Esfahan and Shahr-e Kord, Iran. All samples were analyzed for aflatoxin M 1 (AFM 1 ) contamination by ELISA and 213 (90.3%) were positive with mean concentrations 65 ng.l −1 . These concentrations are lower than the standards of Codex Alimentarius and FDA (500 ng.l −1 ), but 119 samples (55.9%) had higher concentrations than the maximum tolerance accepted by some European countries (50 ng.l −1 ). Mean concentrations of AFM 1 in raw, pasteurized and UHT milk were 68, 56, and 65 ng.l −1 , respectively. Mean concentrations of AFM 1 in autumn and winter samples were significantly higher (P<0.05) than those of spring and summer but differences between AFM 1 concentrations of spring and summer samples were not significantly different.Concentrations of AFM 1 in milk from Shahr-e Kord were significantly lower (P≤0.05) than those from Esfahan.

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The objective of this study was to determine the prevalence of Listeria spp. in sea food samples in Isfahan and Shahrekord, Iran. From April 2009 to January 2010, a total of 264 samples of fresh and frozen fish and shrimp samples were obtained from randomly selected retail stores in Isfahan and Shahrekord, Iran. The samples were tested for the presence of Listeria spp. using a selective enrichment and isolation protocol recommended by the United States Department of Agriculture. Only Listeria monocytogenes isolates identified by bacteriological methods were tested by polymerase chain reaction (PCR). Using conventional bacteriologic methods, out of the total of 264 samples examined, 20 (7.6%) were found to be positive for Listeria. Listeria species were isolated in 7.5%, 4.2%, 11.7% and 6.6% of fresh fish, frozen fish, fresh shrimp and frozen shrimp samples, respectively. Listeria monocytogenes and L. innocua were detected in 1.9% and 5.7% of the samples analyzed, respectively. All five Listeria strains identified as L. monocytogenes were also positive using PCR. Consumption of these sea foods, either raw or undercooked, may contribute to food-borne illness in Iran. Also, L. monocytotenes in raw seafood may pose a health risk in kitchens if contaminating ready-to-eat food.

Close contact of vegetables with soil, polluted water, and animal manure and unsanitary conditions during processing of restaurant salads led us to study the distribution of virulence factors, O-serogroups, and antibiotic resistance properties in Shiga toxigenic Escherichia coli (STEC) isolated from vegetables and salads. Samples of vegetables and salad (n = 420) were collected and evaluated for the presence of E. coli using culture and a PCR assay. Total prevalence of E. coli in studied samples was 49.5%. E. coli was found in 49.6% of vegetable samples and 49% of salad samples. Leek and traditional salad had the highest incidence of E. coli. Significant differences in the incidence of E. coli were found between the hot and cold seasons. Of the 149 E. coli isolates from vegetable samples, 130 (87%) were STEC, and of the 59 E. coli isolates from salad samples, 50 (84%) were STEC. The most commonly detected virulence factors were stx1 and eaeA. A significant difference was found between the frequency of the attaching and effacing and the enterohemorrhagic E. coli subtypes. Serogroups O26 (46% of isolates), O157 (14%), O121 (10%), and O128 (9%) were the most commonly detected serogroups among the STEC strains. The tetA, sul1, aac(3)-IV, dfrA1, blaSHV, and CITM antibiotic resistance genes were found in 96, 47.7, 90, 51, 27, and 93% of isolates, respectively. The highest levels of resistance were found against ampicillin (96.6% of isolates), tetracycline (87%), and gentamicin (90%). This study shows the importance of vegetables and salads as potential sources of E. coli infection.