Detection of mecA gene and methicillin-resistant Staphylococcus aureus (MRSA) isolated from milk and risk factors from farms in Probolinggo, Indonesia
F1000Research
Abstract and Figures
Background: Staphylococcus aureus is commonly found in dairy cows and is a source of contamination in milk. S. aureus that are resistant to beta-lactam antibiotics (especially cefoxitin) are referred to as methicillin-resistant Staphylococcus aureus (MRSA). The spread of MRSA cannot be separated from sanitation management during milking; it can originate from milk collected from the udder or from the hands of farmers during the milking process. The purpose of this study was to examine the level of MRSA contamination in dairy cow's milk and farmer's hand.
Methods: A total of 109 samples of dairy cow’s milk and 41 samples of farmer’s hand swabs were collected at a dairy farm in Probolinggo, East Java, Indonesia. Samples were cultured and purified using mannitol salt agar (MSA). The profile of S. aureus resistance was established by disk diffusion test using a disk of beta-lactam antibiotics, namely oxacillin and cefoxitin.
Results: The S. aureus isolates that were resistant to oxacillin and cefoxitin antibiotics were then tested for oxacillin resistance screening agar base (ORSAB) as a confirmation test for MRSA identity. S. aureus isolates suspected to be MRSA were then tested genotypically by polymerase chain reaction (PCR) method to detect the presence of the mec A gene. The results of the isolation and identification found 80 isolates (53.33%) of S. aureus . The results of the resistance test found that 42 isolates (15%) of S. aureus were resistant to oxacillin and 10 isolates (12.5%) were resistant to cefoxitin. The ORSAB test found as many as 20 isolates (47.62%) were positive for MRSA. In PCR testing to detect the presence of the mec A gene, three isolates (30%) were positive for the mec A gene.
Conclusions: This study shows that several S. aureus isolates were MRSA and had the gene encoding mec A in dairy farms.
Figures - uploaded by Mustofa Helmi Effendi
Author content
All figure content in this area was uploaded by Mustofa Helmi Effendi
Content may be subject to copyright.
... enabling for quick, highly sensitive, and specific identification of these species (Poulsen et al., 2003). Furthermore, and in order to complete the genetic analysis of Staphylococcus sp., the PCR product result that exposed an amplicon size (527bp) of 16S rDNA gene was send for sequences analysis and all sequencing results were analyzed using the Basic Local Alignment Search Tool (BLAST) to compare the sequences to NCBI information and identify any discrepancies, as shown in Tables 2, 3, according to the sequencing results in Table 2 Khairullah et al. (2022), who isolated 80 (53.33%) of S. aureus from 150 milk samples, but agree with the result of another study that conducted by Jahan et al. (2015) who isolated 12 (25.53%) of S. aureus from 47 milk samples regardless the number of S. aureus that could be isolated from milk samples the differences that occur could be attributed to variations in research design, such as residents and geographic distribution of samples, infection control procedures, the kind of antibiotic used for treatment, and poor hygiene procedure during milking, all of which can raise the risk of bacterial contamination in cow's milk (Tohoyessou et al., 2020;Omrani et al., 2020). On the other hand, the phylogenetic tree based on 16SrDNA gene was made by maximum likelihood method as in Figures 5, 6. ...
... The Kirby-Bauer disc diffusion method was used for antimicrobial susceptibility testing as previously described [24]. The presumptive staphylococcal isolates were resuscitated in nutrient broth, after which they were subcultured onto nutrient agar plates and incubated for 18 h at 37 °C. ...
Asthma is a chronic respiratory disease that affects children worldwide. Increasing evidence suggests that Staphylococcus aureus contributes to the pathology of asthma. The aim of this study was to evaluate the nasal carriage, antimicrobial susceptibility profile, and presence of enterotoxin genes from S. aureus isolated from children with asthma. Nasal swab samples were collected from 158 children, including 98 children with asthma and 60 healthy controls. S. aureus isolates were identified using phenotypic methods and the presence of the nuc gene. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Polymerase chain reaction (PCR) confirmed the presence of the mecA gene and enterotoxin genes. The nuc gene was confirmed in 83 isolates, resulting in a nasal carriage of 52.5% (83/158). The nasal carriage of S. aureus was higher among asthma cases (72.4%), with a significant association of S. aureus nasal carriage observed among asthma cases (OR 0.201, 95% CI 0.063–0.645, p = 0.007). Methicillin-resistant S. aureus (MRSA) nasal carriage was 11.4%. The S. aureus isolates showed high resistance to cefoxitin (99%) and penicillin (92%) but were sensitive to gentamicin (25%). Furthermore, 67.5% of the isolates were multi-drug resistant. The staphylococcal enterotoxin c gene (sec) was the most prevalent enterotoxin (19.7%) among cases and controls. These findings highlight the need for improved antibiotic stewardship in paediatric medicine and implementation of infection control policies.
... S. aureus isolates that are resistant to cefoxitin continued to undergo ORSAB as a phenotypic test; however, depending on conditions like temperature, it may also vary throughout growth (Maharjan et al. 2022). As the gold standard for identification, Polymerase Chain Reaction (PCR) is the genotypic test used to identify MRSA from its gene, mecA (Khairullah et al. 2022b). ...
Waruwu YKK, Khairullah AR, Effendi MH, Lukiswanto BS, Afnani DA, Kurniawan SC, Silaen OSM, Riwu KHP, Widodo A, Ramandinianto SC. 2023. Detection of methicillin-resistant Staphylococcus aureus and multidrug resistance isolated from cats in animal clinic at Sidoarjo District, East Java, Indonesia. Biodiversitas 24: 106-111. Methicillin-resistant Staphylococcus aureus is the name given to the strain of bacteria that is multidrug-resistant (MDR) and resistant to β-lactam antibiotics. Compared to other livestock, companion animals have been highlighted more often as potential MRSA reservoirs. This study looked for MDR and cat-derived MRSA strains in Sidoarjo. One hundred cats with nasal swabs were accessed, along with the veterinary hospital and other clinics. Samples were collected using a sterile cotton swab and buffered peptone water as the transport medium, and then identified using a microbiological standard operating procedure. On five different antibiotic discs, the Kirby-Bauer diffusion method was used to determine the S. aureus antibiotic resistance profile. As a confirmatory test for MRSA, S. aureus isolates that were resistant to cefoxitin continued to grow on Oxacillin Resistance Screening Agar Base (ORSAB). Out of the seven MRSA isolates that were assumed to be MRSA, four of the seven MRSA isolates were confirmed to be MDR S. aureus. Humans and companion animals can both act as reservoirs for the recirculation of MRSA strains within the same household because cat nasal swabs resemble nosocomial MRSA and because both are more likely to get colonized than infected. It illustrated how cats might be a health risk to the public and acted as a cautionary tale about the inappropriate use of antibiotics.
In order to contribute to an assessment of the role of food in the risks of transmission of methicillin-resistant Staphylococcus aureus (MRSA), a review was undertaken of research on this microorganism in milk and dairy products published from January 2001 to February 2024. A total of 186 publications were selected, 125 for dairy products and 61 for bulk-tank milk (BTM). MRSA was detected in 68.8% of the research into dairy products and 73.8% of investigations relating to BTM, although in most studies the prevalence was less than 5%. Of the set of S. aureus strains isolated, approximately 30% corresponded to MRSA. The foods most extensively contaminated with this microorganism were raw milk and some types of soft cheese. Determination of the mecA gene on its own is known not to suffice for the detection of all MRSA strains. The great diversity of techniques used to study MRSA in milk and dairy products made it difficult to draw comparisons between studies. It would thus be advisable to develop a standardized protocol for the study of this microorganism in foods.
Background: Mastitis is one of the factors contributing to the health-related decreased milk production and quality for dairy cows. Mastitis in ruminants is a serious bacterial disease caused by Staphylococcus aureus. Staphylococcal bacteria are becoming increasingly resistant to many classes of antibiotics, particularly β-lactam families like the MRSA strain. Laboratory tests are required to determine the level of bacterial resistance and to identify MRSA isolates sourced from dairy cows in Tulungagung District. Methods: 110 milk samples were isolated on MSA media followed by Gram's staining and biochemical tests. Kirby-bauer diffusion test-based assessment of antibiotic sensitivity. The S. aureus isolates that underwent the MRSA identification test were S. aureus isolates that had developed a resistance to β-lactam antibiotics. Result: A total 81 samples of the 110 isolated milk samples were determined to be positive for S. aureus. Out of total isolates, 25 isolates of S. aureus had the highest level of oxacillin resistance. As many as 4 isolates were confirmed to be MultiDrug Resistance (MDR) and 17 MRSA isolates were discovered from 100 samples of dairy cows. Early diagnosis of MRSA infection is crucial since it can be challenging to treat because this type of bacteria is known to be resistant to several drugs and spreads readily.
Background
Methicillin-resistant Staphylococcus aureus (MRSA), is considered a potential and aggressive nosocomial pathogen. It accounts for 50% of S. aureus isolates in tertiary hospitals in Iran, however, there is no sufficient evolutionary and epidemiological investigation about this medically important bacterium. We aimed to study the lineage and evolution of MRSA in Northwest Iran during 2021–2022 based on the obtained phenotypic and genotypic characteristics.
Materials and methods
Seventy-two non-duplicate MRSA isolates were collected from 3 referral hospitals in Tabriz, Ardebil, and Urmia cities. The antimicrobial susceptibility patterns were determined by disk diffusion test and micro broth dilution methods. Thereafter 4 virulence genes (eta, etb, pvl, tst) and 5 types of staphylococcal cassette chromosome mec (SCCmec) were detected by PCR. In the final step, representative isolates were selected to be studied by Multilocus sequence typing (MLST).
Results
The highest resistance was observed to erythromycin and clindamycin at a rate of 76.4%, followed by ciprofloxacin (61.1%), gentamicin (54.2%), rifampin (38.9%), and co-trimoxazole (27.8%). All isolates were susceptible to vancomycin. The virulence genes of etb, pvl, tst, and eta were detected in 50%, 29.2%, 21.8%, and 13.9% of isolates, respectively. SCCmec types III and I were the most prevalent types, followed by types IV, II, and V. MLST analysis revealed 6 sequence types: ST6854, ST5282, ST127, ST7804, ST1607, and ST7784. Two MLST-based clonal complexes (CC8, and CC97) were identified as well.
Conclusion
The ST numbers were non-repetitive. CC8 as a pandemic clone and an individual lineage and clinically significant clade was reported as the most prevalent clonal complex. It is essential periodic evaluations of antibiotic susceptibility patterns and study the evolutionary characteristics of medical-challenging microorganisms in particular MRSA to effectively treat and restrict the outbreaks.
Over the past ten years, the rise of bacterial disease resistance to antibiotics has presented challenges for veterinarians treating pets. Every day direct contact between pets and their owners is a risk for the spread of harmful bacteria. One of the most frequent patients in veterinary hospitals or clinics is cats. The prevalence of S. aureus infection is rising and becoming more serious as a result of antibiotic resistance, or what is known as multi-drug resistance (MDR). Pet owners and their pets may carry MDR S. aureus through zoonotic transmission. In 2018, MDR events were reported to infect ICU patients at Madiun City Hospital, East Java, Indonesia. Based on this backdrop, the authors decided to perform a study on the S. aureus bacteria resistance test of cefoxitin, tetracycline, erythromycin, gentamicin, and ampicillin bacteria obtained from cat nasal swabs in Madiun City. Making an MSA medium is the first step in bacterial isolation. Then, the Gram stain test identifies the species of Gram bacteria present in the colony. The following step is the catalase and coagulase assays, pinpointing the S. aureus bacterium. The Kirby Bauer disc diffusion method was used to conduct an antibiotic sensitivity test. With the aid of tweezers, paper discs containing the medicines cefoxitin 30 µg, tetracycline 30 µg, erythromycin 15 µg, gentamicin 10 µg and ampicillin 10 µg, are set apart from one another by 25 to 30 mm on an MHA medium. According to sample examination findings, S. aureus was present in 80 (80%), and six isolates (7.5%) were confirmed to be Multi-drug Resistance (MDR). The spread of MDR bacteria in people and animals can result in recurrent infections, a rise in complications, and an increase in morbidity and mortality. Furthermore, rational antibiotic use must be made for both humans and animals to stop the emergence of antibiotic resistance in the veterinary clinic in Madiun City. © 2023, Society for Indonesian Biodiversity. All rights reserved.
Methicillin-resistant Staphylococcus aureus (MRSA) is a S. aureus strain resistant to β-lactam antibiotics and is often associated with livestock, known as livestock-associated (LA)-MRSA. Using molecular typing with multi-locus sequence typing, MRSA clones have been classified in pigs, including clonal complex 398. Livestock-associated-methicillin-resistant S. aureus was first discovered in pigs in the Netherlands in 2005. Since then, it has been widely detected in pigs in other countries. Livestock-associated-methicillin-resistant S. aureus can be transmitted from pigs to pigs, pigs to humans (zoonosis), and humans to humans. This transmission is enabled by several risk factors involved in the pig trade, including the use of antibiotics and zinc, the size and type of the herd, and the pig pen management system. Although LA-MRSA has little impact on the pigs' health, it can be transmitted from pig to pig or from pig to human. This is a serious concern as people in direct contact with pigs are highly predisposed to acquiring LA-MRSA infection. The measures to control LA-MRSA spread in pig farms include conducting periodic LA-MRSA screening tests on pigs and avoiding certain antibiotics in pigs. This study aimed to review the emerging LA-MRSA strains in pig farms.
Staphylococcus aureus is one of the main pathogens causing mastitis in dairy animals worldwide. It is an important opportunistic pathogen of raw milk, and the enterotoxin causes significant food poisoning. Monitoring the antibiotic resistance of S. aureus in raw milk is helpful for a risk assessment of S. aureus . In this study, 62 strains (43.1%) of S. aureus were isolated from 144 retail raw milk samples of different varieties from four regions in northern Xinjiang, China. Among them, the isolation rates at Shihezi, Hami, Altay, and Tacheng were 58.1% (54/93), 12.9% (4/31), 18.2% (2/11), and 22.2% (2/9), respectively. The isolation rate of positive strains in cow milk samples was the highest (61.7%, 37/60), followed by camel milk (35.9%, 23/64), and horse milk (10.0%, 2/20). The results of the classical virulence genes test showed that 12.9% (8/62) of the isolates carried at least one virulence gene. The main genotype was see (6.5%, 4/62), followed by sea + sec (3.2%, 2/62), sea (1.6%, 1/62), and sec (1.6%, 1/62). The analysis of 13 resistance genes and the susceptibility to 12 different antibiotics of 62 isolates showed that 80.6% (50/62) of the strains were resistant to at least one antibiotic, and 46.8% (29/62) were resistant to three or more antibiotics. The isolated strains had the highest resistance rate to penicillin (72.6%, 45/62), and 25.8% (16/62) of the isolates carried the blaZ resistance gene. In addition, 32 strains (51.6%, 32/62) of methicillin-resistant S. aureus were detected. All isolates had the ability to form biofilms. The pulsed-field gel electrophoresis results showed that the 47 isolates revealed 13 major pulsotypes (P1–P13) and 26 subtypes with 80% similarity, indicating the overall genetic diversity in the distribution area and sources of the samples. These findings indicate that S. aureus causes serious pollution of raw milk in northern Xinjiang, which has a negative effect on public health. Therefore, control measures and continuous monitoring should be undertaken to ensure the quality and safety of raw milk.
Staphylococcal infections are among the most common foodborne diseases. We performed the antibiotic susceptibility and molecular characterization of S. aureus from milk samples of dairy cows in Manhiça District. We observed a high frequency of S. aureus (41%, 58/143), in which 71% (41/58) were from commercial farms and 29% (17/58) from smallholder farms. Half of the isolates (50%, 29/58) were resistant to at least one antibiotic, with higher rates of resistance to penicillin (43%, 25/58), followed by tetracycline (16%, 9/58). Multidrug-resistant and methicillin-resistant S. aureus isolates were rare (5%, 3/58 and 3%, 2/58, respectively). The genetic diversity was low, with predominance of human-adapted strains being: ST1/CC1-t5388 (78%) and ST152-t1299 (10%), followed by ST8/CC8-t1476 (5%) and ST5/CC5-t002 (3%) and lastly, ST508/CC45-t331 and ST152-t355, with 2% each. The Panton–Valentine leukocidin (PVL) gene was detected among 14% (8/58) of the isolates, while genes encoding staphylococcal enterotoxins were scarce (3%, 2/58). Our findings revealed a high frequency of S. aureus, with high rates of resistance to the antibiotics commonly used in veterinary and human medicine. Further investigations focusing on the molecular epidemiology of S. aureus from cattle and farmers will provide detailed insights on the genetic relatedness between the strains.
Milk production is an important livelihood source for smallholder dairy farmers in low-to-middle-income countries (LMICs) such as Kenya. However, milk quality and safety are a challenge due to unhygienic handling and non-adherence to food safety standards. The objective of this study was to investigate the knowledge, attitudes and adoption of milk quality and food safety practices by smallholder farmers in Kenya. Ten Focus Group Discussions (FGDs), involving 71 smallholder farmers, were held to collect qualitative data on knowledge, attitudes and practices (KAPs) of smallholder dairy farmers in Laikipia, Nakuru, and Nyandarua counties. Additionally, data were collected through a cross-sectional administered to 652 smallholder farming households.
The results of the study revealed low knowledge level and negative attitudes towards respecting antibiotics treatment withdrawal periods, milk quality standards and food safety regulations. Farmers stated they had received low levels of training on milk quality and safety standards. The majority of farmers adopted animal health measures and hygienic measures such as hand washing and udder cleaning. However, unhygienic milking environments, the use of plastic containers, the use of untreated water, and lack of teat dipping compromised milk quality and safety. Currently, milk production, handling and consumption could expose actors along the dairy value chain to health risks. The adoption of milk quality and food safety practices was influenced by farmers’ knowledge, socioeconomic characteristics, and choice of marketing channel.
There is a need to improve farmers’ knowledge and attitudes and implement hygienic control, disease control and antibiotic residue control practices in the milk production process to meet required milk quality and food safety standards. Awareness campaigns and training programmes for smallholder dairy farmers could foster behavioural change and lead to an improvement in milk quality in Kenya.
Inefficiency of medical therapies used in order to cure patients with bacterial infections requires not only to actively look for new therapeutic strategies but also to carefully select antibiotics based on variety of parameters, including microbiological. Minimal inhibitory concentration (MIC) defines in vitro levels of susceptibility or resistance of specific bacterial strains to applied antibiotic. Reliable assessment of MIC has a significant impact on the choice of a therapeutic strategy, which affects efficiency of an infection therapy. In order to obtain credible MIC, many elements must be considered, such as proper method choice, adherence to labeling rules, and competent interpretation of the results. In this paper, two methods have been discussed: dilution and gradient used for MIC estimation. Factors which affect MIC results along with the interpretation guidelines have been described. Furthermore, opportunities to utilize MIC in clinical practice, with pharmacokinetic /pharmacodynamic parameters taken into consideration, have been investigated. Due to problems related to PK determination in individual patients, statistical estimation of the possibility of achievement of the PK/PD index, based on the Monte Carlo, was discussed. In order to provide comprehensive insights, the possible limitations of MIC, which scientists are aware of, have been outlined.
Staphylococcus aureus (S. aureus) infections are a major healthcare challenge and new treatment alternatives are needed. S. aureus septic arthritis, a debilitating joint disease, causes permanent joint dysfunction in almost 50% of the patients. S. aureus bacteremia is associated with higher mortalities than bacteremia caused by most other microbes and can develop to severe sepsis and death. The key to new therapies is understanding the interplay between bacterial virulence factors and host immune response, which decides the disease outcome. S. aureus produces numerous virulence factors that facilitate bacterial dissemination, invasion into joint cavity, and cause septic arthritis. Monocytes, activated by several components of S. aureus such as lipoproteins, are responsible for bone destructions. In S. aureus sepsis, cytokine storm induced by S. aureus components leads to the hyperinflammatory status, DIC, multiple organ failure, and later death. The immune suppressive therapies at the very early time point might be protective. However, the timing of treatment is crucial, as late treatment may aggravate the immune paralysis and lead to uncontrolled infection and death.
Staphylococcus aureus is one of the most frequent worldwide causes of morbidity and mortality due to an infectious agent. This pathogen can cause a wide variety of diseases, ranging from moderately severe skin infections to fatal pneumonia and sepsis. Treatment of S. aureus infections is complicated by antibiotic resistance and a working vaccine is not available. There has been ongoing and increasing interest in the extraordinarily high number of toxins and other virulence determinants that S. aureus produces and how they impact disease. In this review, we will give an overview of how S. aureus initiates and maintains infection and discuss the main determinants involved. A more in-depth understanding of the function and contribution of S. aureus virulence determinants to S. aureus infection will enable us to develop anti-virulence strategies to counteract the lack of an anti-S. aureus vaccine and the ever-increasing shortage of working antibiotics against this important pathogen.
Staphylococcus aureus is one of the causes in the case of Foodborne Disease, with the resulting toxin triggering the occurrence of Foodborne Intoxication. The purpose of this study was to identify multidrug resistant patterns and detect Methicillin Resistance Staphylococcus aureus (MRSA) in cow's milk in East Java, Indonesia. A total of 170 cow's milk samples were taken from dairy farms on 3 Districs, then the bacteria were cultured and purified using Mannitol Salt Agar media. Resistance tests were carried out with 5 antibiotics on Mueller Hinton Agar media and Methicillin Resistant Staphylococcus aureus (MRSA) by Oxacillin Resistance Screen Agar Base (ORSAB). The results showed there were 76 (44.7%) S. aureus, then antibiotic testing showed 13 (17.1%) S. aureus isolates had multidrug resistant (MDR) properties on the antibiotics tested and 84.6% isolates with MDR confirmed MRSA properties by ORSAB. It was concluded that the raw milk can be a potential reservoir for MDR and MRSA strains to threat public health.
Staphylococcus species are considered as one of the major pathogens causing outbreaks of food poisoning. The aim of this work was to assess the toxinogenic and antibiotic susceptibility profiles of the strains of Staphylococcus spp isolated from three types of fermented dairy products (yoghourt, millet dêguê, and couscous dêguê). The isolation of the Staphylococcus strains was performed on selective media, and their identification was done using biochemical and molecular methods. The susceptibility at 15 antibiotics tested was assessed using the disc diffusion method. The immunodiffusion method was used to evaluate the toxin (luk-E/D, luk-S/F, ETA, and ETB) production. Biofilm formation was qualitatively researched on microplates. Less than half (42.77%) of the collected samples were contaminated with Staphylococcus spp. The yoghourt and millet dêguê samples collected in the afternoon were more contaminated than those collected in the morning. The S. aureus, S. capitis, and S. xylosus strains, respectively, were the most present. S. aureus was the only coagulase-positive species identified in our samples. The highest resistance to antibiotics was observed with penicillin (100%) irrespective of the nature of the sample. S. aureus strains were highly (71.4%) resistant to methicillin. The S. aureus strains were the most biofilm-forming (27.6%), followed by S. capitis strains. Panton and Valentine's leukocidin (luk-S/F) was produced by only S. aureus strains at a rate of 8.33%. Only coagulase-negative Staphylococcus (CNS) produced Luk-E/D. The high rates of Staphylococci contamination indicate bad hygiene quality during the production and distribution of dairy products. It is, therefore, necessary to improve the quality of fermented milk products.
Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogenic strain of bacteria in humans and animals that can cause anything from mild to severe infections. Detection of MRSA in foodstuffs of animal origin has been widely reported and has raised public concerns about the transmission of MRSA from foodstuffs of animal origin to humans. There have been many reports of MRSA infections originating from dairy cow's milk, milk products, and MRSA transmission between farmers working in dairy pens and people working in the dairy industry. Significant differences in the spread of cases of MRSA infection originating from milk and milk products have been reported among various countries in the world. This difference may be caused by different livestock production management systems in different countries in the world. Milk and milk products contaminated with MRSA will be a potential transmission of MRSA transmission when consumed by humans and can be a problem for public health. The milking process carried out by farmers and the processing of milk for milk products can be risk factors for transmission of MRSA to humans. Contamination of milk and milk products by MRSA is a major cause of food poisoning. Several antibiotics of choice can be used in treating patients who experience poisoning with milk and milk products such as fluoroquinolone, tetracyclines, lincosamide, and trimethoprim-sulfamethoxazole. Adherence to good hygiene practices during milking, processing and handling of dairy cow milk can significantly minimize MRSA contamination of milk and dairy products.
Background and Aim: Methicillin resistant Staphylococcus aureus (MRSA) has an exponential rate of spread throughout the world and its occurrence rates have been detected in animal / food samples of animal origin. The methicillin resistance (MR) strain is a significant factor in the potential virulence of Staphylococcus aureus such as the presence of Stapylococcal enterotoxin B (SEB) which induces a super antigenic effect. This study aims to detect the presence of SEB gene in MRSA isolates that isolated from cow milk in East Java province. Materials and Methods: Raw cow's milk ingredients were inoculated in enrichment media and mannitol salt agar (MSA) which were then tested using oxacillin and cefoxitin disc diffusion combined with oxacillin screen agar (ORSA) test to detect MRSA strains. All MRSA strains were detected by the SEB gene by the polymerase chain reaction (PCR) method. Results: In this study confirmed 18 MRSA from 150 samples of cow's milk and detected 4 MRSA isolates having SEB gene with product size 478 bp. In Conclusion: Detection of MRSA carrying the SEB gene in milk can have an impact on the public sector / animal health (milk borne disease) and the economy on livestock. It is very necessary to further analyze the relationship between various virulence factors in MRSA isolates that have the potential to be transmitted through cow's milk in East Java.