Antibiogram and phylogenetic diversity of enterotoxigenic Staphylococcus aureus strains from milk products and public health implications

Abstract

Food poisoning caused by Staphylococcus aureus ( S. aureus ) toxins is considered one of the foremost public health threat that usually occurs through the ingestion of raw milk contaminated with staphylococcal enterotoxins. The current study spotlights on the prevalence, antibiogram and genetic diversity of S. aureus enterotoxin genes. One hundred and fifty of raw milk (90) and ice cream (60) samples were randomly collected from local markets from Sadat city, Egypt . S. aureus was recovered from 44% of raw milk and 20% of ice cream samples. The identification for the obtained S. aureus isolates was confirmed through targeting the nuc gene. Antibiogram pattern of 32 S. aureus isolates showed high resistance to Cefoxitin, Sulpha/Trimethoprim, Tetracycline, Norfloxacin, Penicillin and Cephradine. However, high susceptibility to Gentamycin and Vancomycin were observed. Multiplex PCR was a competent practise for the recognition of Staphylococcus enterotoxin (SE) genes ( SEA , SEB and SED ). The phylogenetic analysis of the SED gene of enterotoxigenic S. aureus strains showed identical similarity with 100% to each other and high similarity with other international isolates in GenBank from different localities and sources. The frequency of enterotoxigenic S. aureus strains in milk products could have serious hazardous effects on humans. These results suggested possible strains transmission between different geographical areas through the food and milk product trades.

Prevalence and Molecular Characterization of Mycoplasma Species, Pasteurella multocida, and Staphylococcus aureus Isolated from Calves with Respiratory Manifestations

“…Several Egyptian and global studies performed the comparative sequence analysis of S. aureus isolated from bovine subclinical mastitis and various food sources [16,[51][52][53]. A previous study employing the 16S rRNA genes sequencing and microarray analysis revealed six clonal complexes of S. aureus recovered from household cattle and buffaloes in Egypt [54].…”

Prevalence and Characterization of Coagulase Positive Staphylococci from Food Products and Human Specimens in Egypt

“…Similar findings were obtained by Mohammed and Hafez [ 33 ] in Egypt, who detected high resistance against chloramphenicol and ampicillin (100%), streptomycin (66.6%), gentamicin and trimethoprim-sulphamethoxazole (33.3%), and erythromycin (16.6%). In a recent study in Egypt, S. aureus demonstrated extreme resistance to cefoxitin, penicillin, cephradine, tetracycline, trimethoprim-sulphamethoxazole, and norfloxacin in samples from raw milk and ice cream [ 4 ]. In China, Wu and colleagues [ 32 ] also recorded high resistance of S. aureus isolated from retail meat and meat products against penicillin (84.6%), ampicillin (85.4%), erythromycin (52.7%), tetracycline (49.3%), kanamycin (45.3%), telithromycin (30.1%), clindamycin (29.6%), streptomycin (21.1%), norfloxacin (20.4%), gentamicin (19.4%), fusidic acid (18.4%), and ciprofloxacin (16.9%).…”

“…Globally, S. aureus causes widely distributed opportunistic, nosocomial, and population-related diseases [ 3 ]. A recent report stated that S. aureus strains can spread to different geographical regions through food and milk products [ 4 ]. According to a surveillance study in India, a lack of hygienic procedures during processing and post-processing handling of food products, particularly those of animal origins such as eggs, meat, and milk, facilitated microbial contamination [ 5 ].…”

Molecular detection of Staphylococcus aureus enterotoxin genes isolated from mastitic milk and humans in El-Behira, Egypt

“…Another study was conducted in Egypt and confirmed the existence of the nuc gene in all S. aureus strains [45,46]. This contrasts with the results published by Abdeen et al [47] who found that approximately 70% of S. aureus isolates carried the nuc gene.…”