Genotypic analyses of IncHI2 plasmids from enteric bacteria.

Incompatibility (Inc) HI2 plasmids are large (typically > 200 kb), transmissible plasmids that encode antimicrobial resistance (AMR), heavy metal resistance (HMR) and disinfectants/biocide resistance (DBR). To better understand the distribution and diversity of resistance-encoding genes among IncHI2 plasmids, computational approaches were used to evaluate resistance and transfer-associated genes among the plasmids. Complete IncHI2 plasmid (N = 667) sequences were extracted from GenBank and analyzed using AMRFinderPlus, IntegronFinder and Plasmid Transfer Factor database. The most common IncHI2-carrying genera included Enterobacter (N = 209), Escherichia (N = 208), and Salmonella (N = 204). Resistance genes distribution was diverse, with plasmids from Escherichia and Salmonella showing general similarity in comparison to Enterobacter and other taxa, which grouped together. Plasmids from Enterobacter and other taxa had a higher prevalence of multiple mercury resistance genes and arsenic resistance gene, arsC, compared to Escherichia and Salmonella. For sulfonamide resistance, sul1 was more common among Enterobacter and other taxa, compared to sul2 and sul3 for Escherichia and Salmonella. Similar gene diversity trends were also observed for tetracyclines, quinolones, ß-lactams, and colistin. Over 99% of plasmids carried at least 25 IncHI2-associated conjugal transfer genes. These findings highlight the diversity and dissemination potential for resistance across different enteric bacteria and value of computational-based approaches for the resistance-gene assessment.

Dry eye symptoms and digital eyestrain - Emerging epidemics among university students due to online curriculum amid the COVID-19 pandemic. A cross-sectional study.

Purpose: Increased screen time has been a major concern among the students who have adopted the online curriculum amid the pandemic. The study was conducted to shed light on the changing trends of symptoms pertaining to dry eye disease and digital eyestrain due to the online curriculum and its negative implications on the ocular health of students. Methods: A cross-sectional study was conducted among students of Manipal Academy of Higher Education who are currently following the E-learning curriculum amid the COVID-19 pandemic the participants were surveyed using a pre-validated structured questionnaire. Results: The mean age of study participants was 23.33 ± 4.604 years. In total, 97.9% (321/352) of the respondents experienced at least three symptoms associated with the usage of digital devices. 88.1% of the participants were exposed to an average screen time of more than 4 hours per day. An increased number of hours of digital device usage was found to be associated with higher total symptom scores (P = 0.04). The total symptom scores were found to be considerably higher for those with continuous contact with the screen (P = 0.02). Headache (69.9%, n = 246) is the most commonly reported symptom followed by neck pain (65.3%, n = 230), tearing (44.6%, n = 157), eye pain (40.9%, n = 144), and burning sensation (40.1%, n = 141). Conclusion: This study highlights a tremendous increase in the prevalence of symptoms related to dry eye and digital eyestrain among students attending online classes during the COVID-19 pandemic. Eye care professionals need to be aware of this emerging public health threat and the appropriate measures for its prevention.

Microbial Genetics and Clonal Dissemination of Salmonella enterica Serotype Javiana Isolated from Human Populations in Arkansas, USA

Salmonella is estimated to cause over a million infections and ~400 deaths annually in the U.S. Salmonella enterica serotype Javiana strains (n = 409) that predominantly originated from the State of Arkansas over a six-year period (2003 to 2008) were studied. This period coincided with a rapid rise in the incidence of S. Javiana infections in the U.S. Children under the age of 10 displayed the highest prevalence of S. Javiana infections, regardless of sex or year of detection. Antimicrobial susceptibility to 15 different antimicrobials was assessed and 92% (n = 375) were resistant to at least one of the antimicrobials. Approximately 89% of the isolates were resistant to sulfisoxazole alone and 3% (n = 11) were resistant to different antimicrobials, including gentamicin, ciprofloxacin or ceftiofur. The pulsed-field gel electrophoresis (PFGE) analyses assessed the genotypic diversity and distribution of S. Javiana strains using XbaI restriction. Nine major clusters were identified and isolates from each group were digested with the restriction enzyme AvrII. Isolates with identical profiles of XbaI and AvrII were found to be disseminated in human populations. These distinct "types" of S. Javiana were persistent in human populations for multiple years. A subset of isolates (n = 19) with unique resistance phenotypes underwent plasmid and incompatibility (Inc) type analyses and the isolates resistant to more than one antimicrobial harbored multiple plasmids (<3 to 165 kb). Furthermore, these strains possessed 14 virulence genes, including pagC, cdtB, and iroN. The whole genome sequences (WGS) of 18 isolates that mostly originated from Arkansas from 2003 to 2011 were compared with isolates collected from different areas in the U.S. in 1999, indicating the perseverance of S. Javiana in disseminating antimicrobial resistance and virulence genes.

Effect of heterogeneous substrate adhesivity of follower cells on speed and tension profile of leader cells in primary keratocyte collective cell migration.

In single keratocyte motility, membrane tension is reported to be high at cell-fronts and believed to establish front coherence. To understand role of membrane mechanics in collective cell migration, we study membrane height fluctuations in cell sheets from fish scales using interference reflection microscopy (IRM). We report the monolayer to have cells lacking substrate adhesion and show that such 'non-sticky' cells can form bridges between leader cells and far-away follower cells. Do such interactions alter motility and membrane mechanics in such leaders? We find non-significant, but reduced speed for leaders with 'non-sticky' followers in comparison to other leaders. Cells show high phenotypic variability in their membrane fluctuation tension profiles. On average, this tension is found to be lower at cell fronts than the mid-section. However, leaders with non-sticky followers are more prone to display higher tension at their front and have a negative correlation between cell speed and front-mid tension difference. Thus, we conclude that intracellular tension gradients are heterogeneous in cell sheets and substrate adhesivity of followers can control the coupling of the gradient to cell speed.

Detection of SARS-CoV-2 in conjunctival secretion and tears in patients with COVID-19 in a tertiary care centre, South India. .

Aims and objectives: Purpose of this study is to detect the presence of SAR-CoV-2 viral RNA in conjunctival secretions of COVID-19 patients and to compare the RT-PCR positivity rate for SARS-CoV-2 in conjunctival and nasopharyngeal swab. Materials and method: Eighty hospitalised COVID-19 patients whose nasopharyngeal swab tested positive for SARS-CoV-2 by RT-PCR were included in the study. Conjunctival swab was collected from eyes of these patients and sent for detection of SARS-CoV-2 by RT-PCR method. Results: Among the eighty patients, 51 (63.7%) were males and 29 (36.3%) were females. The mean age of the patients was 55.93 ± 16.59. Six patients had ocular manifestations. Eleven (13.75%) patients tested positive on conjunctival swab for SARS-CoV-2 viral RNA and only one of them had ocular manifestations out of the eleven. Conclusion: In our study the presence of SARS-CoV-2 in conjunctival secretions of COVID-19 patients was detected and this was not dependent on presence of ocular manifestations or duration of disease. Though the conjunctival positivity is lower compared to the nasopharyngeal swab sampling, ocular surface and secretions can be a potential route of viral transmission.

Urine protein: Urine creatinine ratio correlation with diabetic retinopathy.

PURPOSE: To investigate the urine protein (UP) and urine creatinine (UC) ratio in diabetes mellitus and report its influence as a risk factor for the presence and severity of diabetic retinopathy (DR). METHODS: In total, 150 diabetic patients presenting to the outpatient department were included. Detailed history with informed consent and ophthalmic examination, including visual assessment, external ocular examination, anterior segment evaluation, dilated fundus examination by slit-lamp biomicroscopy, and indirect ophthalmoscopy, was done. The early morning spot urine sample was used to determine spot urine protein creatinine ratio. Association with hypertension, fasting blood sugar (FBS), and HBA1C (glycosylated Hb) were also noted. RESULTS: Urinary PCR increased with the severity of the diabetic retinopathy (P < 0.001). HbA1c, FBS, and duration of diabetes had a direct correlation with urine PCR. ROC curve analysis showed that the optimal PCR cut-off value for predicting the risk of onset DR was 0.65. Retinopathy progressed with increasing urine PCR. Spot urine PCR strongly correlates with stages of diabetic retinopathy and proteinuria measured in 24-h urine samples. CONCLUSION: The study showed that urine PCR can be a marker for risk and progression of diabetic retinopathy.

Pragmatic Strategy for Fecal Specimen Storage and the Corresponding Test Methods for Clostridioides difficile Diagnosis.

The quality of fecal specimens is one of the factors responsible for successful Clostridioides difficile infection (CDI) diagnosis. The quality depends largely on the storage conditions, including the temperature and time period. In this study, we organized the outputs of previous studies, filled experimental gaps in the knowledge of storage conditions, and introduced a pragmatic strategy for fecal storage for CDI diagnosis. A 5-step pathway was adopted to develop the fecal specimen storage strategy as follows: step 1, bibliomic analysis; step 2, experimental gap-filling; step 3, comparative evaluation; step 4, strategy development; step 5, internal review. Step 1 identified eight articles providing experimental information on the effects of fecal specimen storage conditions on the effectiveness of C. difficile detection methods. Step 2 provided additional quantitative data on C. difficile vegetative and spore cell viability and DNA stability. All previous and current results were compared (step 3). In step 4, fir general and nine special strategies were developed, followed by an internal review of the overall approaches (step 5). It is recommended to separate fecal samples into aliquots before testing and storing them. It is particularly recommended that fecal specimen samples be stored for CDI diagnosis at 4 °C for up to 60 days for all test methods.

Mycotic keratitis due to Cylindrocarpon lichenicola: Successful salvage of the eye.

We hereby report a successfully salvaged eye due to mycotic keratitis by Cylindrocarpon lichenicola in a 60-year-old female from Kasaragod (Kerala). The patient came with a history of pain, photophobia and decreased vision of the right eye. The microbiological investigations of the corneal scraping revealed C. lichenicola. C. lichenicola is a soil saprophyte. Since the ulcer worsened paracentesis followed by therapeutic keratoplasty and adjunct therapy with natamycin drops, voriconazole drops and oral ketoconazole was given. We stress that evidence-based timely medical and surgical intervention helped in the restoration of the vision in an infected eye.

Genotypic and Phenotypic Characterization of Incompatibility Group FIB Positive Salmonella enterica Serovar Typhimurium Isolates from Food Animal Sources.

Salmonella enterica is one of the most common bacterial foodborne pathogens in the United States, causing illnesses that range from self-limiting gastroenteritis to more severe, life threatening invasive disease. Many Salmonella strains contain plasmids that carry virulence, antimicrobial resistance, and/or transfer genes which allow them to adapt to diverse environments, and these can include incompatibility group (Inc) FIB plasmids. This study was undertaken to evaluate the genomic and phenotypic characteristics of IncFIB-positive Salmonella enterica serovar Typhimurium isolates from food animal sources, to identify their plasmid content, assess antimicrobial resistance and virulence properties, and compare their genotypic isolates with more recently isolated S. Typhimurium isolates from food animal sources. Methods: We identified 71 S. Typhimurium isolates that carried IncFIB plasmids. These isolates were subjected to whole genome sequencing and evaluated for bacteriocin production, antimicrobial susceptibility, the ability to transfer resistance plasmids, and a subset was evaluated for their ability to invade and persist in intestinal human epithelial cells. Results: Approximately 30% of isolates (n = 21) displayed bacteriocin inhibition of Escherichia coli strain J53. Bioinformatic analyses using PlasmidFinder software confirmed that all isolates contained IncFIB plasmids along with multiple other plasmid replicon types. Comparative analyses showed that all strains carried multiple antimicrobial resistance genes and virulence factors including iron acquisition genes, such as iucABCD (75%), iutA (94%), sitABCD (76%) and sitAB (100%). In 17 cases (71%), IncFIB plasmids, along with other plasmid replicon types, were able to conjugally transfer antimicrobial resistance and virulence genes to the susceptible recipient strain. For ten strains, persistence cell counts (27%) were noted to be significantly higher than invasion bacterial cell counts. When the genome sequences of the study isolates collected from 1998-2003 were compared to those published from subsequent years (2005-2018), overlapping genotypes were found, indicating the perseverance of IncFIB positive strains in food animal populations. This study confirms that IncFIB plasmids can play a potential role in disseminating antimicrobial resistance and virulence genes amongst bacteria from several food animal species.

Critical Slowing Down at the Abrupt Mott Transition: When the First-Order Phase Transition Becomes Zeroth Order and Looks Like Second Order.

We report that the thermally induced Mott transition in vanadium sesquioxide shows critical slowing down and enhanced variance ("critical opalescence") of the order parameter fluctuations measured through low-frequency resistance-noise spectroscopy. Coupled with the observed increase of the phase-ordering time, these features suggest that the strong abrupt transition is controlled by a critical-like singularity in the hysteretic metastable phase. The singularity is identified with the spinodal point and is a likely consequence of the strain-induced long-range interaction.

Whole-Genome Sequences of 66 Incompatibility Group FIB Plasmid-Carrying Salmonella enterica Serovar Typhimurium Isolates from Food Animal Sources.

Sixty-six Salmonella enterica serovar Typhimurium isolates carrying incompatibility group FIB (IncFIB) plasmids were sequenced to further characterize the IncFIB plasmid-encoded factors associated with virulence and antimicrobial resistance genes. In addition to the IncFIB plasmid, many of these isolates harbored additional plasmids encoding virulence and antimicrobial resistance genes.

Using the Theory of Planned Behavior to Understand Factors Influencing South Asian Consumers' Intention to Seek Pharmacist-Provided Medication Therapy Management Services.

The study purpose was to use the theory of planned behavior to understand factors influencing South Asian consumers' intention to seek pharmacist-provided medication therapy management services (MTMS). Specific objectives were to assess effects of attitude, subjective norm (SN), perceived behavioral control (PBC), and socio-demographics on South Asian consumers' intention to seek MTMS. Participants who were ≥18 years of age, of South Asian origin, with a previous visit to a pharmacy in the US for a health-related reason, and with ability to read and comprehend English were recruited from independent pharmacies in New York City. Responses were obtained through a self-administered survey. Descriptive statistics were performed, and multiple linear regression analysis was conducted to assess the study objective. SPSS was used for data analyses. Out of 140 responses, 133 were usable. Mean scores (standard deviation) were 4.04 (0.97) for attitude, 3.77 (0.91) for SN, 3.75 (0.93) for PBC, and 3.96 (0.94) for intention. The model explains 80.8% of variance and is a significant predictor of intention, F (14,118) = 35.488, p < 0.05. While attitude (ß = 0.723, p < 0.05) and PBC (ß = 0.148, p < 0.05) were significant predictors of intention, SN (ß = 0.064, p = 0.395) was not. None of the socio-demographics were significant predictors of intention. Strategies to make South Asians seek MTMS should focus on creating positive attitudes and removing barriers in seeking MTMS.

Immunomagnetic Capture of Big Six Shiga Toxin-Producing Escherichia coli Strains in Apple Juice with Detection by Multiplex Real-Time PCR Eliminates Interference from the Food Matrix.

Having reliable methods for detecting Shiga toxin-producing Escherichia coli (STEC) in foods is an important food safety goal. The majority of STEC outbreaks have involved either the O157:H7 serotype or one of six non-O157 serogroups, O26, O45, O103, O111, O121, and O145, termed "The Big Six." We have compared detection by PCR of the Shiga toxin genes stx1a and stx2a from STEC bacteria isolated from unclarified apple juice by simple centrifugation with the use of an immunocapture technique to minimize contaminants (such as pectin and polyphenols that may copurify with DNA) that may interfere with DNA amplification efficiencies and limit sensitivity. An internal control for successful immunocapture, DNA extraction, and PCR amplification was generated by introducing the pmRaspberry plasmid into an stx null strain, yielding an E. coli O45 pmRaspberry derivative that can be added to food samples directly. Using serial dilutions of a representative Big Six STEC in apple juice, our immunocapture method resulted in a 50% probability of detection value of 3.34, 2.25, and 4.25 CFU for detection by multiplex real-time PCR, growth on solid agar, and multiplex endpoint PCR, respectively. The time to result was 6.5 h, 9.5 h, and 1.5 days for immunocapture of Big Six STECs and detection by multiplex real-time PCR, endpoint PCR, and growth on solid agar, respectively. A set of 52 Big Six STEC isolates and 30 non-Big Six STEC strains was used to establish the inclusivity and exclusivity of the method. Finally, the ability to detect Big Six STEC contamination reliably was confirmed at 4.5 and 45 CFU/25-mL portions of refrigerated apple juice.

Effects of Medication Nonadherence and Comorbidity on Health Resource Utilization in Schizophrenia.

BACKGROUND: Medication nonadherence to antipsychotic drugs, which is commonly seen in patients with schizophrenia who have comorbidities, not only affects the quality of life of individuals suffering from the condition, but can also lead to worsening of disease condition, adverse outcomes, excessive use of health care resources, and higher medical costs. OBJECTIVE: To determine the effect of nonadherence to antipsychotics and related disease comorbidities on medical care utilization with respect to inpatient hospital visits, outpatient visits, office visits, and emergency room (ER) visits. METHODS: Retrospective, cross-sectional research data was obtained from the Medical Expenditure Panel Surveys (MEPS) for the years 2010-2014. The proportion of days covered (PDC) adherence measure was used to identify and classify individuals as adherent (PDC ≥ 80%) or nonadherent (PDC < 80%). A logistic regression analysis was used to further examine the effect of key study variables and comorbidity on medication nonadherence in patients with schizophrenia. Using the Student's t-test, population characteristics were statistically compared between the adherent and nonadherent populations and between populations with comorbidities and without comorbidities with respect to inpatient, outpatient, office, and ER visits. RESULTS: Of 1.2 million people who reported having schizophrenia in MEPS from 2010 to 2014, as many as 71% were found to be nonadherent to antipsychotic medications (PDC < 80%). Results showed that women (OR = 3.594, 95% CI = 1.33-11.40, P = 0.030) and people with less than 15 years of education (OR = 20.85, 95% CI = 3.91-111.09, P = 0.0005) were more likely to be nonadherent to antipsychotic medications than all other demographics. Compared with the adherent schizophrenia population (n = 353,349), the nonadherent population (n = 868,737) had greater utilization of outpatient visits (0.68 vs. 1.92, P < 0.0001) and office visits (10.95 vs. 18.21, P < 0.0001) but had lower utilization of inpatient visits (0.82 vs. 0.45, P < 0.0001) and ER visits (1.03 vs. 0.79, P = 0.1036). Compared with the schizophrenia population without comorbidities, the population with comorbidities (a classification based on a Charlson Comorbidity Index score of ≥ 1) had greater utilization of inpatient (0.39 vs. 0.76, P < 0.0001); office (13.39 vs. 19.34, P < 0.0001); and ER visits (0.39 vs. 1.41, P < 0.0001) but had lower utilization of outpatient visits (1.86 vs. 1.21, P < 0.0001). CONCLUSIONS: Greater medical care resources are used by nonadherent populations with schizophrenia and comorbidities than those without comorbidities. Together, nonadherence and comorbidities pose significant risks to patients with schizophrenia, in clinical and financial terms, and addressing problems stemming from such risks should be an area of priority in schizophrenia management. DISCLOSURES: No outside funding supported this study. The authors have no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Impact of co-carriage of IncA/C plasmids with additional plasmids on the transfer of antimicrobial resistance in Salmonella enterica isolates.

BACKGROUND: Antimicrobial resistance in Salmonella enterica is often plasmid encoded. A key resistance plasmid group is the incompatibility group (Inc) A/C plasmids that often carry multiple resistance determinants. Previous studies showed that IncA/C plasmids were often co-located with other plasmids. The current study was undertaken to evaluate the impact of plasmid co-carriage on antimicrobial resistance and plasmid transfer. METHODS: A total of 1267 Salmonella isolates, representing multiple serotypes and sources were previously subjected to susceptibility testing and 251 isolates with resistance to at least 5 antimicrobial agents were identified for further study. Each isolate was subjected to PCR-based replicon typing, and those with IncA/C plasmids were selected for plasmid isolation, PCR-based mapping of IncA/C plasmid backbone genes, and conjugation assays to evaluate resistance plasmid transferability. RESULTS: Of the 87 identified IncA/C positive isolates, approximately 75% carried a plasmid with another identified replicon type, with the most common being I1 (39%), FIA, FIIA, FIB and HI2 (each 15%). PCR-based mapping indicated significant diversity in IncA/C backbone content, especially in regions encoding transfer-associated and hypothetical proteins. Conjugation experiments showed that nearly 68% of the isolates transferred resistance plasmids, with 90% containing additional identified plasmids or larger (>50 kb) non-typeable plasmids. CONCLUSIONS: The majority of IncA/C-positive strains were able to conjugally transfer antimicrobial resistance to the recipient, encoded by IncA/C and/or co-carried plasmids. These findings highlight the importance of co-located plasmids for resistance dissemination either by directly transferring resistance genes or by potentially providing the needed conjugation machinery for IncA/C plasmid transfer.

Evaluation of the Genetics and Functionality of Plasmids in Incompatibility Group I1-Positive Salmonella enterica.

Salmonella is a predominant foodborne pathogen in the United States and other countries. Mobile genetic elements such as plasmids allow Salmonella to adapt to external stress factors such as nutrient deprivation and host factors. Incompatibility group I1 (IncI1) plasmid-carrying Salmonella enterica strains were examined to determine the presence of plasmid-associated genes and their influence on phenotypic characteristics. The objective of this study was to understand the genetic determinants on IncI1 plasmids and their impact on antimicrobial susceptibility, competitive growth inhibition of Escherichia coli, and plasmid transfer. Primers were designed for genes that play a role in virulence, antimicrobial resistance, and plasmid transfer based on previously sequenced IncI1 plasmids. Polymerase chain reaction assays were conducted on 92 incompatibility group I1 (IncI1)-positive S. enterica strains. Phenotypic characterization included conjugation assays, antimicrobial susceptibility testing, and bacteriocin production based on the inhibition of growth of colicin-negative E. coli J53. The antimicrobial resistance genes aadA1, tetA, sul1, and blaCMY were detected in 88%, 87%, 80%, and 48% of the strains, respectively. Over half of the strains were resistant or intermediately resistant to streptomycin (85%), sulfonamides (76%), tetracycline (74%), and ampicillin (68%) and 57% of the strains inhibited growth of E. coli J53 strain. Among putative virulence genes, colicin-associated colI and cib were detected in 23% and 35% of strains and imm and ccdA were present in 58% and 54% of strains, respectively. Approximately 61% of strains contained plasmids that conjugally transferred antimicrobial resistance, including 83% where the recipient received IncI1 plasmids. Most of the strains carried an assortment of transfer associated (pil and tra) genes with between 63% and 99% of strains being positive for individual genes. Taken together the study affirms that IncI1 plasmids likely play roles in the dissemination of antimicrobial resistance and virulence-associated factors among enteric organisms.

Draft Genome Sequences of Salmonella enterica Isolates Containing Incompatibility Group I1 Plasmids from Swine, Poultry, and Human Sources.

The draft genome sequences of eight Salmonella enterica isolates from various sources were evaluated for the influence of incompatibility group I1 (IncI1) plasmids on virulence. Strains SE142, SE143, SE144, and SE146 originated from swine, SE36N and SE89N from poultry-related sources, and SE991 and SE1148 from human patients.

Development of a Flow Cytometry-Based Method for Rapid Detection of Escherichia coli and Shigella Spp. Using an Oligonucleotide Probe.

Standard methods to detect Escherichia coli contamination in food use the polymerase chain reaction (PCR) and agar culture plates. These methods require multiple incubation steps and take a long time to results. An improved rapid flow-cytometry based detection method was developed, using a fluorescence-labeled oligonucleotide probe specifically binding a16S rRNA sequence. The method positively detected 51 E. coli isolates as well as 4 Shigella species. All 27 non-E. coli strains tested gave negative results. Comparison of the new genetic assay with a total plate count (TPC) assay and agar plate counting indicated similar sensitivity, agreement between cytometry cell and colony counts. This method can detect a small number of E.coli cells in the presence of large numbers of other bacteria. This method can be used for rapid, economical, and stable detection of E. coli and Shigella contamination in the food industry and other contexts.

Molecular Characterization of Salmonella enterica Serovars Isolated from a Turkey Production Facility in the Absence of Selective Antimicrobial Pressure.

This study evaluated antimicrobial resistance and virulence factors in Salmonella enterica isolated from a turkey flock in which the birds were raised in an environment where antimicrobials were not administered to the birds, either through feed or water. Salmonella was isolated from turkeys and various environmental samples in the facility using conventional microbiological procedures. Isolates were serotyped and analyzed phenotypically by antimicrobial resistance profiling and genotypically by pulsed-field gel electrophoresis (PFGE) fingerprinting, integron analysis, plasmid profiling, replicon-based incompatibility (Inc) group typing, and virulence gene profiling. Ninety-five S. enterica isolates were isolated from cecal contents (n = 29), feed (n = 22), leftover feed (n = 13), litter (n = 12), drinkers (n = 10), environment (n = 8), and an insect. The following serotypes were identified: Montevideo (24%), Anatum (22%), Agona (17%), Kentucky and Worthington (12%), Senftenberg (11%), and rough phenotypes (3%). The majority of isolates (61/95; 64%) were susceptible to 12 antimicrobials tested; however, despite the absence of antimicrobials in the facility, approximately 36% of the isolates were resistant to two to five antimicrobials. Class 1 integrons were detected in 8% of the isolates. The integron sequence analysis revealed dihydrofolate reductase (dhfr) and aminoglycoside adenylyl transferase (aadA2) genes, which encode trimethoprim and streptomycin resistance, respectively. Furthermore, 71% of the isolates had at least one plasmid. There were five plasmid replicon types identified among the isolates, including IncI1, IncHI2, IncFIIA, IncB/O, and IncP, with variable prevalence among the serotypes. All 95 isolates tested polymerase chain reaction-positive for 19 virulence genes and negative for virD4 and virB4. The virulence gene profiles were similar within the isolates from the same serotype. Within particular serotypes, PFGE patterns revealed 100% similarity, even when the bacterial strains were isolated from different sources, indicating cross-colonization of sources within the turkey facility. On this antibiotic-free turkey farm, turkeys and feed appeared to be the major reservoirs of multidrug-resistant Salmonella, which harbored multiple virulence genes.