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Recent Progress in Nutrition

(ISSN 2771-9871)

Recent Progress in Nutrition (ISSN 2771-9871) is an international peer-reviewed Open Access journal published quarterly online by LIDSEN Publishing Inc. This periodical is devoted to publishing high-quality papers that describe the most significant and cutting-edge research in all areas of nutritional sciences. Its aim is to provide timely, authoritative introductions to current thinking, developments and research in carefully selected topics. Also, it aims to enhance the international exchange of scientific activities in nutritional science and human health.

Recent Progress in Nutrition publishes high quality intervention and observational studies in nutrition. High quality systematic reviews and meta-analyses are also welcome as are pilot studies with preliminary data and hypotheses generating studies. Emphasis is placed on understanding the relationship between nutrition and health and of the role of dietary patterns in health and disease.

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Current Issue: 2025  Archive: 2024 2023 2022 2021
Open Access Original Research

Occurrence of Multidrug Resistant Escherichia coli & Escherichia coli O157:H7 in Raw Cow Milk from Dhaka, Bangladesh

Md. Robeul Islam 1 ORCID logo, Avijit Banik 1 ORCID logo, Hasnain Anjum 1, 2 ORCID logo, Nusrat Nabila Fariha 1 ORCID logo, Zarin Rushni 1 ORCID logo, Maruf Abony 1, 3 ORCID logo, Dipa Rani Bhowmik 1, ORCID logo Zakaria Ahmed 4, * ORCID logo

  1. Department of Microbiology, Primeasia University, Dhaka, Bangladesh

  2. Jashore University of Science and Technology, Jashore, Bangladesh

  3. Ludwig-Maximilians-Universität München, Munich, Germany

  4. Bangladesh Jute Research Institute, Dhaka, Bangladesh

* Correspondence: Zakaria Ahmed ORCID logo

Academic Editor: Charles Odilichukwu R. Okpala

Special Issue: Dairy Food Safety and Fermentation

Received: May 01, 2025 | Accepted: December 01, 2025 | Published: December 09, 2025

Recent Progress in Nutrition 2025, Volume 5, Issue 4, doi:10.21926/rpn.2504025

Recommended citation: Islam MR, Banik A, Anjum H, Fariha NN, Rushni Z, Abony M, Bhowmik DR, Ahmed Z. Occurrence of Multidrug Resistant Escherichia coli & Escherichia coli O157:H7 in Raw Cow Milk from Dhaka, Bangladesh. Recent Progress in Nutrition 2025; 5(4): 025; doi:10.21926/rpn.2504025.

© 2025 by the authors. This is an open access article distributed under the conditions of the Creative Commons by Attribution License, which permits unrestricted use, distribution, and reproduction in any medium or format, provided the original work is correctly cited.

Abstract

Enteropathogenic strains of Escherichia coli, like the serotype O157:H7, can cause significant health issues if consumed. Milk and dairy products can serve as a reservoir for the bacteria. Dissemination of multidrug-resistant E. coli through dairy products can become a potential health hazard if consumed. The present study investigates the occurrence of multidrug-resistant E. coli O157:H7 in raw milk obtained from farms and markets around Dhaka, Bangladesh. A Total of 50 milk samples were collected in this study from September 2023 to March 2024, of which 22 were from dairy farms and 28 from market vendors. Isolation and identification of E. coli was conducted through conventional cultural and biochemical methods. Identification of E. coli O157:H7 among the isolates was performed using Sorbitol MacConkey agar, followed by EC-MUG and latex agglutination test. To assess their antimicrobial susceptibility, the isolates were tested against 10 antibiotic groups. A total of 19 milk samples (19/50; 38%) were found to be positive for E. coli, whereas 14% were confirmed as E. coli O157: H7 (7/50). All isolates were susceptible to Meropenem, Imipenem, and Levofloxacin. However, resistance against Cefoxitin, Amoxicillin, and Ceftazidime was found in 85%, 71%, and 85% of the isolates, respectively. The frequent occurrence of E. coli O157:H7 in milk samples obtained and their multidrug-resistant nature observed in this study is alarming for public health. An emphasis on the responsible use of antibiotics, and implementation of improved AMR surveillance to control and reduce AMR load in the Bangladeshi dairy industry should be taken with urgency.

Keywords

E. coli O157:H7; milk; quality test; antibiotics resistance; public awareness

1. Introduction

Every year almost 600 million people fall ill due to the consumption of unhygienic or unsafe food, and diarrheal diseases are one of the major contributors of these cases of foodborne illnesses [1]. Salmonella spp., Campylobacter spp., and Escherichia coli have been the most persistent bacterial agents causing food-borne diarrheal diseases over the years [2]. Among these three pathogens, E. coli is the opportunistic one. The bacterium typically remains in a symbiotic relationship with its host, but in an immunocompromised host, it can cause urinary tract infection, sepsis, or diarrheal diseases [3]. The diarrheagenic E. coli are classified into six major pathotypes: Enteropathogenic E. coli (EPEC), Shiga-Toxin producing E. coli (STEC), Enteroinvasive E. coli (EIEC), Enterotoxigenic E. coli (ETEC), Enteroaggregative E. coli (EAEC), and Diffusely Adherent E. coli (DAEC) [4]. The STEC strains cause food-borne illnesses with symptoms ranging from easily manageable watery diarrhoea, fever, abdominal cramps, to more severe cases like Hemolytic Uremic Syndrome (HUS) and Haemorrhagic Colitis (HC) [5]. E. coli O157:H7 serogroup, a natural flora of ruminant guts, is the most common type of STEC [6]. Although the organism doesn’t cause any illness in cattle, humans can become ill after coming in contact with contaminated animal faeces or consuming contaminated meat or dairy products [7]. The serotype is a highly pathogenic strain as well, with an infectious dose of less than 40 cells [8].

Numerous evidence-backed scientific studies have shown that the consumption of milk and dairy products is essential for meeting the nutritional requirements of the human body and is also linked to protecting from the most prevalent chronic diseases [9]. Due to its high nutrient content, milk can support the growth of pathogens that produce heat-stable toxins and thus act as a source of food-borne illness outbreaks [10]. Milk can be contaminated with food-borne pathogens during the milking process by the milking personnel, utensils used for milking, or microorganisms may enter the udder through the teat canal from the environment [11].

A 1992 E. Coli O157:H7 outbreak that affected thousands of people in Southern Africa and Swaziland was caused by surface water contaminated with animal corpses and cow manure. E. coli O157:H7 infection is thought to be responsible for about 74,000 cases and 61 fatalities every year, according to a report from the United States of America [12]. The majority of E. Coli O157:H7 outbreaks in the 1980s were caused by raw milk and poorly prepared hamburgers. Afterwards, outbreaks were linked to cheese and yogurt, among other dairy products [12,13]. In particular, E. coli O157:H7 has been reported frequently as one of the most dangerous foodborne bacteria that causes major diseases and high human fatality rates worldwide over the last few years [14,15]. Disease outbreaks are caused by this strain in various regions of the world, including the United States, the European Union, and Africa [16,17,18].

Hassan et al. found that 75% of healthy cattle in Bangladesh are the natural reservoir of E. coli; they also reported 43.33% Shiga toxin-producing E. coli (STEC) in cattle faeces, which might be the source of STEC in Humans [11,19]. Moreover, due to the extensive use of antibiotics in the poultry, dairy, and livestock industries of Bangladesh, the emergence of antimicrobial-resistant (AMR) and multidrug-resistant (MDR) zoonotic pathogens has become a pressing concern [20,21]. In a recent study, 88.33% E. coli isolated from livestock and poultry samples in Bangladesh were found to be MDR [22]. Antimicrobial resistance can be transferred from zoonotic pathogens to human pathogens through the exchange of genetic materials between closely related species, during food handling, processing, or after ingestion [23]. As the development of newer and more effective antibiotics is comparatively slower compared to the rise of antimicrobial resistance, the World Health Organization (WHO) views the infections caused by MDR pathogens as a global public health threat [24].

The present study aims to investigate the presence of antibiotic-resistant E. coli and its enteropathogenic serotype O157:H7 in raw cow milk samples to understand the role of dairy products in the dissemination of enteropathogenic bacteria. Findings of this study reveal a significant occurrence of MDR E. coli O157:H7 in raw milk samples, indicating that raw cow milk can serve as an important reservoir for MDR pathogens, and consumption of raw or ill-processed milk and dairy products may become a serious health hazard.

2. Materials and Methods

2.1 Study Area and Duration

This study was conducted from September 2023 to March 2024 in Dhaka, Bangladesh. A total of 5 medium-scale dairy farms hosting ≥20 dairy cows from five locations, including Banani, Banasri, Mohammadpur, Savar, and Uttara, and 3 market areas, such as Savar, Karwan Bazar, and Mohakhali, were randomly selected for sample collection (Table 1; Figure 1). From 5 farms, 22 raw milk samples were collected from randomly selected cows. Additionally, 28 raw milk samples were collected randomly from local milk vendors using aseptic techniques (Table 1). This study did not include cows with any active disease (i.e., mastitis) or recent treatment history.

Table 1 Sampling location and numbers.

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Figure 1 Geographical location of the farms and markets used for sampling in this study (Green colour pinpoint indicate local farms and blue colour pinpoint indicate local market).

2.2 Sample Collection

A total of 50 samples (n = 50) were collected. Samples from farmed cows were collected after cleansing the udders and teat ends with cotton soaked in 70% isopropanol to ensure aseptic conditions. Using a plunger and dipper, 50 ml of the raw milk was collected in a sterile bottle from the milking bucket immediately after milking. For the bacteriological analysis, the samples were transported to the Department of Microbiology, Primeasia University laboratory, using an Icebox, where the samples were kept at 0°C to cease the growth and activity of acid-producing organisms. The examination of milk samples was conducted within 4 hours after collection.

2.3 MBRT Test for Primary Screening of Milk’s Microbial Quality

The standard Methylene Blue Reduction Test (MBRT) was carried out in the laboratory. 0.5 mL of methylene blue was added to 10 mL of a sample, and then it was incubated at 37°C for the MBRT (Figure 2). The time (in hours) for the blue colouration to disappear was measured [25].

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Figure 2 Microbial Quality Screening using MBRT. Here, the decolouration of milk from blue and white indicates viable microbial growth, and the time required for decolouration is indicative of the quality of milk.

2.4 Total Viable Count (TVC) & Total Coliform Count (TCC) Determination of Milk

Samples were serially diluted by a tenfold dilution in sterile normal saline. In a test tube, 1 ml of raw material was first combined with 9 ml of saline to create 101 dilutions. This procedure was then repeated for each sample until 106 dilutions were obtained.

The spread plate method was used to count the total viable bacteria. 0.1 ml of samples from each dilution series was spread on Plate Count Agar (PCA) plates. The incubation process lasted 24 hours at 37°C. Following the incubation time, the plates were examined for the existence of distinct colonies, and the actual number of bacteria was calculated as colony-forming units per milliliter (cfu/ml).

The total coliform count was performed by using the spread plate technique on MacConkey agar medium. 0.1 ml of samples from each dilution series was spread out on MacConkey agar medium. After the incubation time, pink colonies were counted for the Total Coliform Count (cfu/ml) measurement [26,27].

2.5 Isolation and Presumptive Identification of E. coli

Samples were enriched by adding 10 mL of each to 90 mL of sterile EC broths and then incubating at 37°C overnight. After enrichment, a loopful (~10 µl) of enriched culture was inoculated onto MacConkey agar. Pink, non-mucoid colonies were then streaked onto the Eosin Methylene Blue (EMB) agar. The colonies that showed the characteristic green metallic sheen on EMB agar were considered positive for E. coli (Figure 3). The selected isolates were then subjected to conventional biochemical characterization, such as the IMViC test, TSI (Triple Sugar Iron) test, H2S and motility test, oxidase, catalase, starch hydrolysis, and carbohydrate utilization tests (Figure 4). API 20E kits (BioMérieux, Inc.) were used for further biochemical profiling. E. coli ATCC 25922 was used as a positive control for the experiments. Reagents were obtained from Oxoid (UK) and Hi-media (India) [28].

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Figure 3 E. coli showed green metallic sheen on EMB agar.

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Figure 4 Conventional Biochemical Tests Results of (A): E. coli non O157:H7 (From left to right: Lactose Utilization, Sucrose Utilization, Dextrose Utilization, Sorbitol Utilization, Mannitol Utilization, Indole Test, Citrate Utilization, TSI test, Methyl-red test, Voges-Proskauer test); (B): E. coli O157:H7 (From left to right: Lactose Utilization, Dextrose Utilization, Sucrose Utilization, Sorbitol Utilization, Mannitol Utilization, TSI test, Indole Test, Citrate Utilization, Methyl-red test, Voges-Proskauer test).

2.6 Identification of E. coli O157:H7

The presumed E. coli isolates with green metallic sheen were then inoculated onto Sorbitol MacConkey agar to check for the presence of E. coli O157:H7 serotype. Since E. coli O157:H7 cannot ferment sorbitol, they produce characteristic opaque, colourless colonies on Sorbitol MacConkey agar. Appearance of such colonies was presumed to be E. coli O157:H7, and they were subjected to further confirmation tests (Figure 5) [29]. E. coli ATCC 43888 was used as a reference control for this experiment.

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Figure 5 Primary identification of E. coli O157:H7 using sorbitol-MacConkey agar: Here, colourless colonies are indicative of E. coli O157:H7, while non- O157:H7 isolates appear as pink colonies.

2.6.1 β-Glucuronidase Test

As β-glucuronidase activity is absent in E. coli O157:H7, it can be used as a diagnostic tool for differentiation between E. coli O157:H7 and E. coli non-O157:H7 isolates. In this test, the isolates were further cultivated on E. coli Methyl Umbelliferyl Glucuronate (EC-MUG) medium (Oxoid, UK) to check for the presence of β-glucuronidase activity [30]. Following incubation, isolates were exposed to long-wave ultraviolet light (365 nm) to observe fluorescence (Figure 6). Isolates with positive β-glucuronidase activity will break down MUG, creating fluorescence under UV, and are considered non-O157:H7 isolates. Isolates showing negative fluorescence are lacking β-glucuronidase activity and are regarded as O157:H7 isolates [30].

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Figure 6 β-glucuronidase activity of E. coli isolates: Here, isolates with bright blue fluorescence under UV light indicate Positive β-glucuronidase activity, while non-fluorescing isolates appear as negative. Since β-glucuronidase activity is absent in E. coli O157: H7, non-fluorescent isolates are considered positive for E. coli O157:H7.

2.6.2 Latex Agglutination Test

For the serological confirmation of the presumed E. coli O157:H7 strains, the latex agglutination test was performed, which uses latex particles coated with antibodies specific for the E. coli O157 and the E. coli H7 antigen. The test was conducted using a commercially available Wellcolex E. coli O157:H7 Rapid Latex Agglutination Test kit (Oxoid, UK) following the provided instructions [31,32]. Here, reagents consisting of latex particles coated with specific antibodies (O157 and H7) were mixed on a card with a suspension of presumed isolates. Rapid agglutination indicates a specific antigen-antibody reaction and is considered positive for E. coli O157:H7 [31].

2.7 Antibiotic Resistance Determination

The antibacterial susceptibility to various antibiotics was determined using the Kirby-Bauer disc diffusion technique in accordance with the Clinical and Laboratory Standards Institute (CLSI) guidelines [33,34]. Mueller-Hinton agar and antibiotic disks obtained from Oxoid (UK) were used for this experiment. In this study, 15 antibiotics from 8 different classes including fluoroquinolones like Ciprofloxacin (CIP) and Levofloxacin (LEV), cephalosporins like Cefoxitin (FOX), Cefixime (CFM), Ceftazidime (CAZ), Cefepime (FEP) and Ceftriaxone (CRO), carbapenem like Meropenem (MEM) and Imipenem (IPM), aminoglycosides like Gentamicin (CN) and Amikacin (AK), Amoxicillin-Clavulanic Acid (AMC), Azithromycin (AZM), Sulfamethoxazole/trimethoprim (SXT), and Nitrofurantoin (F) were used. Experiments were done in triplicate, and E. coli ATCC 25922 was used as a sensitive control.

Isolates that showed phenotypic resistance to more than two groups of antibiotics were considered multidrug resistant (MDR) [35]. To determine the level of multidrug resistance, the Multiple antibiotic resistance index (MARI) was calculated for the isolates. MARI obtained using the E. coli was calculated using the following formula, outlined in a previous study [36].

\[ MAR=\frac{a}{b} \]

In this formula, (a) - indicates the number of antibiotics exhibiting resistance by the particular isolate, (b) - denotes the total count of antibiotics tested against each isolate.

The values of the MAR index varied from 0 to 1, where values nearer 0 indicated more sensitivity and those nearer 1 indicated high resistance. A considerable level of resistance or a high-risk reservoir of bacterial contamination was suggested by a MAR value of 0.20 or above [36].

2.8 Statistical Analysis

Data generated from this study were verified and entered in Microsoft Excel, followed by IBM SPSS Statistics Data Editor (Version 21) and STATA 15 for subsequent analysis.

3. Results

3.1 Microbial Quality of Milk Samples

The MBRT test revealed that among the 50 samples, 4 changed colour within 30 minutes, and 7 changed color within the first hour. Most of the samples changed color to blue between 5 and 7.5 hours. Only 3 samples didn’t change within 8 hours Table 2. TVC & TCC analysis revealed that Samples 25 and 47 had the highest TVC (7.5 × 109 and 6.8 × 109 cfu/ml, respectively). The sample with the lowest TVC 1.4 × 105 cfu/ml was Sample 16. The presence of coliforms in milk indicates faecal contamination. The highest coliform bacterial count was found in Sample 10 (6.5 × 107 cfu/ml), and the lowest total coliform count was 1.1 × 105 cfu/ml in Sample 30. Following conventional biochemical tests (Table 3) and the API20E tests, a total of 19 (38%) samples out of 50 were found to be contaminated with E. coli.

Table 2 Microbial quality of milk samples.

Table 3 Biochemical tests for identification of E. coli. O157:H7.

3.2 Identification of E. coli O157:H7

Using the latex agglutination test, Sorbitol MacConkey Agar test, and EC-MUG test, 7 (14%) out of 19 E. coli isolates were found to be E. coli O157:H7 serotype.

3.3 Antibiotic Susceptibility Test

As for the E. coli non-O157:H7 isolates, the highest resistance was observed against FOX (69%), CAZ (69%), and AMC (61%) (Figure 7). None of the isolates showed resistance against CIP, MEM, IPM, and LEV. Additionally, 91.66% (11/12) E. coli non O157:H7 were resistant to at least three groups of antibiotics and had a MAR index of over 0.20, and were considered to be MDR (Table 2). In case of E. coli O157:H7 isolates, the highest resistance was against FOX (85%), CAZ (71%), and AMC (71%) (Figure 7). None of the E. coli O157:H7 isolates showed resistance against MEM, IPM, and LEV as well. On top of that, all of the (100%) E. coli O157:H7 samples were found to have an MAR over 0.2, and were considered as MDR (Table 4).

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Figure 7 Antibiotic sensitivity pattern of A. E. coli O157:H7 (n = 12) et B. E. coli non-O157:H7 (n = 7). Here, FOX = Cefoxitin, CFM = Cefixime, CAZ = Ceftazidime, FEP = Cefepime, CRO = Ceftriaxone, SXT = Sulfamethoxazole/trimethoprim, AMC = Amoxicillin-clavulanic acid, AZM = Azithromycin, CN = Gentamicin, F = Nitrofurantoin.

Table 4 Multidrug-resistant pattern in different samples of E. coli non O157:H7 and E. coli O157:H7.

4. Discussion

Milk is not only a highly nutritious drink for humans but also a perfect medium for microbial growth due to its near-neutral pH, high water content, and plenty of nutrients [37]. With growing public awareness regarding food safety in Bangladesh, the need for safe and fresh milk is also on the rise. Unfortunately, most of the dairy farms and milk-based food industries of the country are operating without proper surveillance [27]. As a result, the hygiene and safety profile of the raw milk sold in Bangladesh's local markets is becoming questionable.

The purpose of this study was to determine the frequency of encountering E. coli and E. coli O157:H7 in raw milk from local markets. The samples obtained from farms and markets showed few differences E. coli contamination, as 41% and 36% of farm and market samples were positive for E. coli, respectively (Table 2). In this study, E. coli was detected in 38% of the samples, which correlates with the results from previous studies conducted in Dhaka [22,27]. However, two studies from Mymensingh and Jashore also report 70% and 66% E. coli contamination in raw milk, respectively, indicating a much higher level of occurrence in locations outside Dhaka [38,39].

The occurrence of E. coli O157:H7 in raw milk indicates the pathogen's possible faecal shedding and subsequent milk contamination. The primary host of the bacterium, cattle, can actively excrete the bacteria in their faeces without exhibiting any symptoms, and improper maintenance may lead to milk contamination [7]. The occurrence of E. coli O157:H7 was found to be 14% (Table 3), which is lower than the findings of another study conducted in Jashore (20%) [39].

The emergence of antibiotic-resistant foodborne pathogens and their connection with the indiscriminate use of antibiotics in agriculture, poultry, or livestock industries has become a matter of grave concern globally. The presence of antibiotic residues in food products is believed to be a key contributor to the development of multidrug resistance [40]. In Bangladesh, the presence of multidrug-resistant bacteria in daily consumables such as meat and dairy products has been reported previously and remains a serious concern, as these bacteria are resistant to antibiotics used for both human and animal use [41]. Penicillin, amoxicillin, ampicillin, gentamicin, ciprofloxacin, ceftriaxone, etc., are some of the most commonly used antibiotics in veterinary medicine in Bangladesh [42]. In this study, among the most used antibiotics in veterinary medicine, ciprofloxacin was found to be the most effective, as the isolates showed no resistance against it (Figure 7). The isolates also showed lower resistance against another commonly used veterinary antibiotic, such as gentamicin. This finding contradicts those of Talukder et al. (2016), who reported that the isolates showed 86% and 78% resistance against gentamicin and ciprofloxacin, respectively [43]. The isolates from this study didn’t show resistance to fluoroquinolones, such as ciprofloxacin and levofloxacin, and carbapenems, such as imipenem and meropenem (Figure 7). Rana et al. (2025) also found antibiotics belonging to fluoroquinolone and carbapenem classes to be most effective against their isolated bacterial pathogens [44]. Both groups of O157:H7 and non O157:H7 isolates exhibited similar patterns of resistance, with higher susceptibility to fluoroquinolones, carbapenems and aminoglycosides, while being resistant to β-lactams like cefoxitin, ceftazidime and amoxicillin-clavulanic acid (Table 4; Figure 7). The better efficacy of fluoroquinolones and limited use of carbapenems in veterinary therapeutics may explain such a pattern. However, the isolates here showed the highest resistance (100%) against cefoxitin, ceftazidime, and amoxicillin-clavulanic acid (Figure 7). Among these antibiotics, ceftazidime belongs to the third-generation cephalosporins [45]. Cefepime resistance was notably higher among the O157:H7 isolates compared to the non-O157:H7 isolates (Figure 7). The presence of foodborne pathogens with 100% resistance against a third-generation cephalosporin is alarming, as the WHO identified this class of antibiotics as one of the most critically important antibiotics for human medicine [46]. This may be contributed to by frequent use of β-lactam antibiotics in the dairy industry as veterinary antibiotics, as well as the emerging crisis of rapid ESBL dissemination among bacterial communities.

Although the current study identifies the alarming presence of E. coli O157:H7 in milk, molecular characterization of its virulence is not conducted. Additionally, to understand the resistance mechanisms against necessary antibiotics, an investigation of resistance elements is required. Further molecular investigation of pathogenic and antibiotic resistance elements like Extended-Spectrum β-Lactamases (ESBL) and Plasmid-Mediated Quinolone Resistance genes (PMQR), as well as analysis of potential outbreaks using ERIC-PCR, is currently in process, which could give important insights regarding the dissemination of multidrug-resistant E. coli O157:H7.

5. Conclusion

The results of this study show that raw milk from farms and sold in several marketplaces in Dhaka, Bangladesh, can be heavily contaminated with E. coli and E. coli O157:H7, posing serious health concerns to the general public. Moreover, the emerging threat of multidrug-resistant foodborne pathogens disseminating through essential sources of nutrition, such as milk, is an alarming. Along with the pressing concern of serious foodborne illnesses like gastroenteritis and HUS, the findings also point to a loss of antibiotic options for treating these infections. Milk can serve as a zoonotic element that transfers MDR pathogens from animal to human. Inadequate knowledge of hygiene, hand milking, improper handling, processing, and preserving of milk can lead to heavy microbial growth that can be detrimental to health upon consumption. Findings of this study indicate the possible health issue and suggest the implementation of proper hygiene practices while herding, milking, and processing milk (i.e., pasteurization, ultra-heat treatment), as well as preserving milk and milk-based products in an appropriate environment. It also suggests taking action regarding the use of antibiotics omn cattle farms, which may lead to MDR outbreaks if not addressed. The present study could be further enhanced by investigating the potential dissemination routes as well as evolutionary mechanisms of multidrug-resistant E. coli O157:H7 and other enteropathogenic organisms through cow milk, providing deeper insight into their health impact, and prevention strategies of any potential outbreak. Every stage of milk collection, processing, and marketing, as well as the careless use of antibiotics in dairy cows, should be regulated to ensure food safety and prevent health issues.

Acknowledgments

Author convey thanks to Jannatul Ferdousi, Ruma Aktar and Amit Paul student Department of Microbiology, at Primeasia University for assisting in sample collection and laboratory at this work.

Author Contributions

Md. Robeul Islam: Designed the experiments; Performed the experiments; Analysed and interpreted the data; Wrote the manuscript. Avijit Banik: Contributed materials; Analysed and interpreted the data; Reviewed the manuscript. Hasnain Anjum: Analysed and interpreted the data; Wrote the manuscript; Reviewed the manuscript. Nusrat Nabila Fariha: Wrote the manuscript; Contributed materials; Analysed the data. Zarin Rushni: Wrote the manuscript; Contributed materials; Analysed the data. Maruf Abony: Supervised the project; Funded the project. Dipa Rani Bhowmik: Performed the experiments; Analysed and interpreted the data. Zakaria Ahmed: Designed the experiments; Supervised the project; Funded the project.

Funding

No particular grant was given to this research by funding organizations in the public, private, or not-for-profit Sectors.

Competing Interests

The authors declare no conflict of interest.

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