Wound colonization with methicillin-resistant Staphylococcus aureus and hypotheses about acquisition routes in rural health care settings in Sub-Saharan Africa: Perspective from a center devoted to the treatment of cutaneous neglected tropical diseases.

We identified a high prevalence (46.4%) of wound colonization with methicillin-resistant Staphylococcus aureus (MRSA) in patients hospitalized in a center devoted to the treatment of cutaneous tropical diseases in Benin. The proportion of MRSA among S aureus isolates was 54.3%. Thirty percent of these MRSA were identified in outpatients. The analysis of pulsed-field gel electrophoresis demonstrated an important diversity of strains but also identified 8 small clusters containing between 2 and 4 isolates suggesting cross-transmission.

Evaluation of the Use of Singleplex and Duplex CerTest VIASURE Real-Time PCR Assays to Detect Common Intestinal Protist Parasites.

Cryptosporidium spp., Giardia duodenalis and Entamoeba histolytica are species of protozoa- causing diarrhoea that are common worldwide, while Entamoeba dispar, Dientamoeba fragilis and Blastocystis sp. appear to be commensal parasites whose role in pathogenicity remains controversial. We conducted the clinical evaluation of five singleplex and one duplex CerTest VIASURE Real-Time PCR Assays against a large panel of positive DNA samples (n = 358), and specifically to Cryptosporidium spp. (n = 96), G. duodenalis (n = 115), E. histolytica (n = 25) E. dispar (n = 11), Blastocystis sp. (n = 42), D. fragilis (n = 37), and related parasitic phylum species such as Apicomplexa, Euglenozoa, Microsporidia and Nematoda. DNA samples were obtained from clinical stool specimens or cultured isolates in a national reference centre. Estimated diagnostic sensitivity and specificity values were 0.94-1 for Cryptosporidium spp., 0.96-0.99 for G. duodenalis, 0.96-1 for E. histolytica, 1-1 for E. dispar, and 1-0.99 for D. fragilis in the evaluated singleplex assays. In the duplex assay for the simultaneous detection of Blastocystis sp. and D. fragilis these values were 1-0.98 and 1-0.99, respectively. Measures of diagnostic precision for repeatability and reproducibility were found to be under acceptable ranges. The assays identified six Cryptosporidium species (C. hominis, C. parvum, C. canis, C. felis, C. scrofarum, and C. ryanae), four G. duodenalis assemblages (A, B, C, and F), and six Blastocystis subtypes (ST1-ST5, and ST8). The evaluated singleplex and duplex VIASURE Real-Time PCR assays provide sensitive, practical, and cost-effective choices to the molecular diagnosis of the main diarrhoea-causing intestinal protists in clinical microbiology and research laboratories.

Blood culture quality and turnaround time of clinical microbiology laboratories in Chinese Teaching Hospitals: A multicenter study.

PURPOSE: Blood culture (BC) remains the gold standard for the diagnosis of bloodstream infections. Improving the quality of clinical BC samples, optimizing BC performance, and accelerating antimicrobial susceptibility test (AST) results are essential for the early detection of bloodstream infections and specific treatments. METHODS: We conducted a retrospective multicenter study using 450,845 BC specimens from clinical laboratories obtained from 19 teaching hospitals between 1 January 2021 and 31 December 2021. We evaluated key performance indicators (KPIs), turnaround times (TATs), and frequency distributions of processing in BC specimens. We also evaluated the AST results of clinically significant isolates for four different laboratory workflow styles. RESULTS: Across the 10 common bacterial isolates (n = 16,865) and yeast isolates (n = 1011), the overall median (interquartile range) TATs of AST results were 2.67 (2.05-3.31) and 3.73 (2.98-4.64) days, respectively. The specimen collections mainly occurred between 06:00 and 24:00, and specimen reception and loadings mainly between 08:00 and 24:00. Based on the laboratory workflows of the BCs, 16 of the 19 hospitals were divided into four groups. Time to results (TTRs) from specimen collection to the AST reports were 2.35 (1.95-3.06), 2.61 (1.98-3.32), 2.99 (2.60-3.87), and 3.25 (2.80-3.98) days for groups I, II, III, and IV, respectively. CONCLUSION: This study shows the related BC KPIs and workflows in different Chinese hospitals, suggesting that laboratory workflow optimization can play important roles in shortening time to AST reports and initiation of appropriate timely treatment.

Modifying Escherichia coli to mimic Shigella for medical microbiology laboratory teaching: a new strategy to improve biosafety in class.

Introduction: Laboratory teaching of medical microbiology involves highly pathogenic microorganisms, thus posing potential biosafety risks to the students and the teacher. To address these risks, non/low-pathogenic microorganisms were modified to mimic highly pathogenic ones or highly pathogenic microorganisms were attenuated directly using the CRISPR/Cas9 technology. This study describes the modification of Escherichia coli DH5α to mimic Shigella and its evaluation as a safe alternative for medical laboratory teaching. Methods: To generate E. coli DH5α△FliC△tnaA2a, the tnaA and FliC genes in E. coli DH5α were knocked out using CRISPR/Cas9 technology; a plasmid bearing the O-antigen determinant of S. flexneri 2a was then constructed and transformed. Acid tolerance assays and guinea pig eye tests were used to assess the viability and pathogenicity, respectively. Questionnaires were used to analyze teaching effectiveness and the opinions of teachers and students. Results: The survey revealed that most teachers and students were inclined towards real-time laboratory classes than virtual classes or observation of plastic specimens. However, many students did not abide by the safety regulations, and most encountered potential biosafety hazards in the laboratory. E. coli DH5α△FliC△tnaA2a was biochemically and antigenically analogous to S. flexneri 2a and had lower resistance to acid than E. coli. There was no toxicity observed in guinea pigs. Most of teachers and students were unable to distinguish E. coli DH5α△FliC△tnaA2a from pure S. flexneri 2a in class. Students who used E. coli DH5α△FliC△tnaA2a in their practice had similar performance in simulated examinations compared to students who used real S. flexneri 2a, but significantly higher than the virtual experimental group. Discussion: This approach can be applied to other high-risk pathogenic microorganisms to reduce the potential biosafety risks in medical laboratory-based teaching and provide a new strategy for the development of experimental materials.

Extra-urogenital infection by Mycoplasma hominis in transplant patients: two case reports and literature review.

BACKGROUND: Mycoplasma hominis is a facultative anaerobic bacterium commonly present in the urogenital tract. In recent years, M. hominis has increasingly been associated with extra-urogenital tract infections, particularly in immunosuppressed patients. Detecting M. hominis in a diagnostic laboratory can be challenging due to its slow growth rate, absence of a cell wall, and the requirements of specialized media and conditions for optimal growth. Consequently, it is necessary to establish guidelines for the detection of this microorganism and to request the appropriate microbiological work-up of immunosuppressed patients. CASE PRESENTATION: We hereby present two cases of solid organ transplant patients who developed M. hominis infection. Microscopic examination of the bronchial lavage and pleural fluid showed no microorganisms. However, upon inoculating the specimens onto routine microbiology media, the organism was successfully identified and confirmation was performed using 16S rDNA sequencing. Both patients received appropriate treatment resulting in the resolution of M. hominis infection. CONCLUSIONS: The prompt detection of M. hominis in a clinical specimen can have a significant impact on patient care by allowing for early intervention and ultimately resulting in more favorable clinical outcomes, especially in transplant patients.

Microbiology at Home (M@H): an Online, Self-Paced Solution To Enhance Practical Skills in Foundation Microbiology.

The online education market share is rapidly increasing, raising the demand to teach sciences outside the laboratory environment. Here, we present Microbiology at Home (M@H), a new approach that integrates hands-on microbiology experimentation with online interactive simulations using authentic scenarios in microbiology in the home environment. The M@H program includes 8 practical activities aligned to the ASM curriculum for practical skills. M@H kits are mailed to students, and each practical activity is prepacked individually with the required consumables, including microbial culture media to prepare at home using a microwave. These practicals are self-paced, and each activity is facilitated using a two-dimensional simulation package with prerecorded videos, protocols, and interactive activities. The students receive both synchronous and asynchronous support and guidance through online learning management systems fora and virtual gatherings. The M@H program was applied to an Introductory Microbiology cohort at the University of New England in 2020 and 2021. Based on student feedback, the experience not only provided real hands-on practice in microbiology but also acted to cement the engagement with the content by contextualizing it to the surrounding home environment. We anticipate that these activities will provide a way to successfully engage students with hands-on microbiology without the need for actual laboratory attendance, thus increasing accessibility to microbial protocols and applications.

Less Is More: When to Repeat Antimicrobial Susceptibility Testing.

This study investigated the frequency of change of the antimicrobial susceptibility pattern when the same isolate was found in the same patient in various situations. We used laboratory data collected over a period of 8 years (January 2014 to December 2021) at the clinical microbiology laboratory of a tertiary hospital for Escherichia coli, Klebsiella pneumoniae, Enterobacter spp., Pseudomonas aeruginosa, and Staphylococcus aureus. Antimicrobial susceptibility tests (AST) were performed using Vitek 2 automated system. We determined essential agreement and categorical agreement, and introduced the new terms essential MIC increase and change from nonresistant to resistant to present changes in antimicrobial susceptibility over time. During the study period, 18,501 successive AST were included. The risk for S. aureus to be resistant to any antibiotic upon repeated culture was <10% during a follow-up of 30 days. For Enterobacterales, this risk was approximately 10% during a follow-up of 7 days. For P. aeruginosa, this risk was higher. The longer the follow-up period, the higher the risk that the bacteria would show phenotypic resistance. We also found that some drug-bug combinations were more likely to develop phenotypical resistance (i.e., E. coli/amoxicillin-clavulanic acid and E. coli/cefuroxime). A potential consequence of our finding is that if we regard a risk of resistance below 10% as acceptable, it may be feasible to omit follow-up AST within 7 days for the microorganisms investigated in this study. This approach saves money, time, and will reduce laboratory waste. Further studies are needed to determine whether these savings are in balance with the small possibility of treating patients with inadequate antibiotics.

Development of Online Clinical Microbiology Laboratory Unknowns: Active Learning for Online, Hybrid, and In-Person Courses.

Microbiology laboratory classes allow students to make connections between theoretical concepts and clinical practice through experiential learning. In the past, most laboratory sessions were taught in-person, on-site. However, advances in multimedia and the ability of learning management systems to provide online course delivery allow laboratory assignments to be taught through online simulations. An online unknown identification activity promotes active learning while allowing instructors to assess student knowledge. This article describes the creation of online clinical microbiology unknown assignments which are suitable for complementing a variety of microbiology courses in an online, hybrid, or in-person format.

An Upper-Division, Remote Microbiology Laboratory That Blends Virtual and Hands-on Components to Promote Student Success during the COVID-19 Pandemic.

The COVID-19 shutdown forced many institutions of higher education to shift in-person teaching to emergency remote teaching. This was particularly challenging for laboratory courses, where students are expected to learn hands-on skills needed for their career goals. Here, we describe the transformation of an upper-division microbiology laboratory to a course that seamlessly integrates online simulations with safe, hands-on experiences that can be done from home. This blended lab course helped students attain learning outcomes similar to those achieved in the in-person class. We illustrate the implementation of Unknown Portfolios to help students gain the data analysis and critical thinking skills needed to identify an unknown microorganism. Our data show that students who took these online courses mastered material as well as students who took the lab in person, demonstrating proficiency in laboratory safety skills, hands-on techniques, and theoretical class content. Last, we explore online adaptations to enhance in-person lab classes, aiming at reducing the accessibility and equity gaps inherited in many courses, as well as discussing challenges that instructors might experience in this process.

Clinical laboratory diagnostics in dentistry: Application of microbiological methods.

Diagnosis and treatment in dentistry are based on clinical examination of the patients. Given that the major oral diseases are of microbial biofilm etiology, it can be expected that performing microbiological analysis on samples collected from the patient could deliver supportive evidence to facilitate the decision-making process by the clinician. Applicable microbiological methods range from microscopy, to culture, to molecular techniques, which can be performed easily within dedicated laboratories proximal to the clinics, such as ones in academic dental institutions. Periodontal and endodontic infections, along with odontogenic abscesses, have been identified as conditions in which applied clinical microbiology may be beneficial for the patient. Administration of antimicrobial agents, backed by microbiological analysis, can yield more predictable treatment outcomes in refractory or early-occurring forms of periodontitis. Confirming a sterile root canal using a culture-negative sample during endodontic treatment may ensure the longevity of its outcome and prevent secondary infections. Susceptibility testing of samples obtained from odontogenic abscesses may facilitate the selection of the appropriate antimicrobial treatment to prevent further spread of the infection.

El papel del laboratorio de microbiología en el diagnóstico de infecciones por bacilos gramnegativos multirresistentes. Importancia de la determinación de mecanismos de resistencias / The role of the microbiology laboratory in the diagnosis of multidrug-resistant Gram-negative bacilli infections. Importance of the determination of resistance mechanisms

Un diagnóstico y tratamiento precoz tiene un impacto importante en la morbimortalidad de las infecciones producidas por bacterias multirresistentes. Los bacilos gramnegativos multirresistentes constituyen la principal amenaza actual en los hospitales y muy especialmente en las unidades de cuidados intensivos. El papel del laboratorio de microbiología es esencial en dar una respuesta rápida y eficaz. En esta revisión se actualiza los procedimientos del laboratorio de microbiología para la detección rápida de los bacilos gramnegativos multirresistentes y de sus determinantes de resistencia. También se estudia el papel del laboratorio en la vigilancia y control de brotes por estas bacterias, incluyendo las técnicas de tipificación. Se destaca la importancia de proporcionar mapas de resistencia normalizados que permitan conocer la situación epidemiológica de las diferentes unidades. Finalmente se revisa la importancia de sistemas de comunicación eficaces para la transmisión de resultados y la toma de decisiones en el manejo de pacientes infectados por bacilos gramnegativos multirresistentes (AU)

Early diagnosis and treatment has an important impact on the morbidity and mortality of infections caused by multidrug-resistant bacteria. Multidrug-resistant gram-negative bacilli constitute the main current threat in hospitals and especially in intensive care units. The role of the microbiology laboratory is essential in providing a rapid and effective response. This review updates the microbiology laboratory procedures for the rapid detection of multidrug-resistant gram-negative bacilli and its resistance determinants. The role of the laboratory in the surveillance and control of outbreaks caused by these bacteria, including typing techniques, is also studied. The importance of providing standardized resistance maps that allow knowing the epidemiological situation of the different units is emphasized. Finally, the importance of effective communication systems for the transmission of results and decision making in the management of patients infected by multidrug-resistant gram-negative bacilli is reviewed (AU)

The role of the microbiology laboratory in the diagnosis of multidrug-resistant Gram-negative bacilli infections. The importance of the determination of resistance mechanisms.

Early diagnosis and treatment has an important impact on the morbidity and mortality of infections caused by multidrug-resistant bacteria. Multidrug-resistant gram-negative bacilli (MR-GNB) constitute the main current threat in hospitals and especially in intensive care units (ICU). The role of the microbiology laboratory is essential in providing a rapid and effective response. This review updates the microbiology laboratory procedures for the rapid detection of BGN-MR and its resistance determinants. The role of the laboratory in the surveillance and control of outbreaks caused by these bacteria, including typing techniques, is also studied. The importance of providing standardized resistance maps that allow knowing the epidemiological situation of the different units is emphasized. Finally, the importance of effective communication systems for the transmission of results and decision making in the management of patients infected by BGN-MR is reviewed.

The Hidden Crisis in the Times of COVID-19: Critical Shortages of Medical Laboratory Professionals in Clinical Microbiology.

The COVID pandemic has put a spotlight on laboratory medicine, showcasing how vital diagnostic testing is for society and the health care system. It has also brought to light and accelerated the critical shortage of trained and experienced laboratory personnel that has been felt for decades. The need for laboratory professionals is expected to grow by 11% between 2020 and 2030, a higher rate of growth than the overall average for all other health care occupations. Here, the background to this workforce shortage is reviewed. Some proposed actions to help address the issue are put forth, including increasing awareness of the medical laboratory science profession along with bolstering training opportunities and awareness of alternate routes to obtaining certification as a medical laboratory scientist. In addition, recent survey data specifically related to the employee shortages in microbiology are presented which demonstrate that 80% of microbiology laboratories have vacant positions and that filling these positions is challenging for a number of reasons, including a lack of qualified applicants.

Molecular epidemiology and clinical characteristics of hepatitis D virus infection in Canada.

Background & Aims: HDV affects 4.5-13% of chronic hepatitis B (CHB) patients globally, yet the prevalence of HDV infection in Canada is unknown. To investigate the prevalence, genotype, demographics, and clinical characteristics of HDV in Canada, we conducted a retrospective analysis of (1) HDV antibody and RNA positivity among referred specimens, and (2) a cross-sectional subset study of 135 HDV seropositive +/-RNA (HDV+) patients compared with 5,132 HBV mono-infected patients in the Canadian HBV Network. Methods: Anti-HDV IgG-positive specimens collected between 2012 and 2019 were RNA tested and the genotype determined. Patients enrolled in the Canadian HBV Network were >18 years of age and HBsAg-positive. Clinical data collected included risk factors, demographics, comorbidities, treatment, fibrosis assessment, and hepatic complications. Results: Of the referred patients, 338/7,080 (4.8%, 95% CI 4.3-5.3) were HDV seropositive, with 219/338 RNA-positive (64.8%, 95% CI 59.6-69.7). The HDV+ cohort were more likely to be born in Canada, to be White or Black/African/Caribbean than Asian, and reporting high-risk behaviours, compared with HBV mono-infected patients. Cirrhosis, complications of end-stage liver disease, and liver transplantation were significantly more frequent in the HDV+ cohort. HDV viraemia was significantly associated with elevated liver transaminases and cirrhosis. Five HDV genotypes were observed among referred patients but no association between genotype and clinical outcome was detected within the HDV+ cohort. Conclusions: Nearly 5% of the Canadian HBV referral population is HDV seropositive. HDV infection is highly associated with risk behaviours and both domestic and foreign-born patients with CHB. HDV was significantly associated with progressive liver disease highlighting the need for increased screening and surveillance of HDV in Canada. Lay summary: Evidence of HDV infection was observed in approximately 5% of Canadians who were infected with HBV referred to medical specialists. HDV-positive patients were more likely to be male, born in Canada, or White or Black/African/Caribbean compared to Asian, and to have reported high-risk activities such as injection or intranasal drug use or high-risk sexual contact compared with patients infected with only HBV. Patients infected with HDV were also more likely to suffer severe liver disease, including liver cancer, compared with HBV mono-infected patients.

Antilogic, a new supervised machine learning software for the automatic interpretation of antibiotic susceptibility testing in clinical microbiology: proof-of-concept on three frequently isolated bacterial species.

OBJECTIVE: Antibiotic susceptibility testing (AST) is necessary in order to adjust empirical antibiotic treatment, but the interpretation of results requires experience and knowledge. We have developed a machine learning software that is capable of reading AST images without any human intervention and that automatically interprets the AST, based on a database of antibiograms that have been clinically validated with European Committee on Antimicrobial Susceptibility Testing rules. METHODS: We built a database of antibiograms that were labelled by senior microbiologists for three species: Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. We then developed Antilogic, a Python software based on an original image segmentation module and supervised learning models that we trained against the database. Finally, we blind tested Antilogic against a validation set of 5100 photos of antibiograms. RESULTS: We trained Antilogic against a database of 18072 pictures of antibiograms. Overall agreement against the validation set reached 97% (16 855/17 281) regarding phenotypes. The severity rate of errors was also evaluated: 1.66% (287/17 281) were major errors and 0.80% (136/17 281) were very major errors. After implementation of uncertainty quantifications, the rate of errors decreased to 0.80% (114/13 451) and 0.42% (51/13 451) for major and very major errors respectively. DISCUSSION: Antilogic is the first machine learning software that has been developed for AST interpretation. It is based on a novel approach that differs from the typical diameter measurement and expert system approach. Antilogic is a proof of concept that artificial intelligence can contribute to faster and easier diagnostic methods in the field of clinical microbiology.

The unintended contribution of clinical microbiology laboratories to climate change and mitigation strategies: a combination of descriptive study, short survey, literature review and opinion.

OBJECTIVE: Climate change poses a significant threat to humanity and human activity is largely responsible for it. Clinical microbiology laboratories have their unintended shares in carbon dioxide (CO2) emissions. The aim of this study is to estimate CO2 emission of a clinical microbiology laboratory and to propose initiatives to reduce the emissions. METHODS: CO2 emission of instruments was estimated based on their electricity consumption. CO2 emitted in producing consumables was estimated by weighing the consumables needed to perform major tests in a large academic hospital. A systematic literature review was performed to identify studies on the impact of clinical microbiology laboratories on the environment. A short survey was sent to four major manufacturers of agar plates on initiatives to reduce the environmental impact of their products. Opinion was given on activities that can reduce CO2 emission in laboratories. RESULTS: The study shows that the largest amount of CO2 emission in the microbiological laboratories comes from consumables and personnel commuting. For example, the production and transportation of agar plates needed to culture samples for a year in a hospital with 1320 beds result in 16 590 kg CO2 is emitted. All survey participants mentioned that they were committed to reduce environmental impact of their products. The initiatives to reduce CO2 emission can be performed at the laboratory and at policy level, such as reducing the number of tests to only the necessary amount to reduce consumables. DISCUSSION: The calculations contribute to map CO2-related emissions in clinical microbiology laboratory activities, and the proposed initiatives to reduce the CO2 may serve as starting point for further discussions.

Acetobacter tropicalis bacteraemia in an immunocompromised patient: case report.

Introduction. The published literature characterizing the bacterial genus Acetobacter primarily explores the role of these organisms in the fermentation industry. Reports of human infections caused by Acetobacter species are rare and are primarily associated with immunocompromised patients. Case Presentation. A young patient with refractory acute myeloid leukaemia received a peripheral blood stem cell transplant at our institution. Both pre- and post-transplant courses were complicated by polymicrobial bloodstream infections. During this time a bacterium, later identified as Acetobacter tropicalis , was isolated from blood cultures. A. tropicalis was recovered in consecutive blood cultures for approximately 1 week; during this time the patient's condition deteriorated, ending in fatal cardiorespiratory failure. Conclusion. This case provides the first report of a human infection with A. tropicalis , although the significance of this finding in a complex patient is hard to establish. This illustrates how the routine implementation of molecular identification techniques by clinical microbiology laboratories will result in the reporting of more rare or novel micro-organisms involved in human infections.

Research on the scaffolding teaching in the theory teaching of Clinical Microbiology Laboratory Technology / 中华医学教育探索杂志

The scaffolding teaching is a kind of "student-centered" teaching desgin. In this study, the teacher breaks down complex content into simply conceptual framework so as to enable students to define their learning objectives, provide help for students' learning, and guide students to think independently and explore cooperatively to construct their own knowledge system. Clinical Microbiology Laboratory Technology is a specialized course with very complicated theoretical contents, which can break up the whole into parts by scaffolding instruction, combined with the learning strategies of cooperation, exploration and mind mapping. Finally, "installment fixed deposit" is realized by induction and summary. The scaffolding teaching model promotes students' ability of autonomous learning, analytical reasoning and innovation.

Integrating Scalable Genome Sequencing Into Microbiology Laboratories for Routine Antimicrobial Resistance Surveillance.

Antimicrobial resistance (AMR) is considered a global threat, and novel drug discovery needs to be complemented with systematic and standardized epidemiological surveillance. Surveillance data are currently generated using phenotypic characterization. However, due to poor scalability, this approach does little for true epidemiological investigations. There is a strong case for whole-genome sequencing (WGS) to enhance the phenotypic data. To establish global AMR surveillance using WGS, we developed a laboratory implementation approach that we applied within the NIHR Global Health Research Unit (GHRU) on Genomic Surveillance of Antimicrobial Resistance. In this paper, we outline the laboratory implementation at 4 units: Colombia, India, Nigeria, and the Philippines. The journey to embedding WGS capacity was split into 4 phases: Assessment, Assembly, Optimization, and Reassessment. We show that on-boarding WGS capabilities can greatly enhance the real-time processing power within regional and national AMR surveillance initiatives, despite the high initial investment in laboratory infrastructure and maintenance. Countries looking to introduce WGS as a surveillance tool could begin by sequencing select Global Antimicrobial Resistance Surveillance System (GLASS) priority pathogens that can demonstrate the standardization and impact genome sequencing has in tackling AMR.

Agar Art: a CURE for the Microbiology Laboratory.

We previously developed and assessed "The Art of Microbiology," a course-based undergraduate research experience (CURE) which uses agar art to spur student experimentation, where we found student outcomes related to science persistence. However, these outcomes were not correlated with specific activities and gains were not reported from more than one class. In this study, we explored which of the three major activities in this CURE-agar art, experimental design, or poster presentations-affected student engagement and outcomes associated with improved understanding of the nature of science (NOS). The Art of Microbiology was studied in three microbiology teaching laboratories: at a research university with either the CURE developer (18 students) or a CURE implementer (39 students) and at a community college with a CURE implementer (25 students). Our quasi-experimental mixed methods study used pre/post-NOS surveys and semi-structured class-wide interviews. Community college students had lower baseline NOS responses but had gains in NOS similar to research university students post-CURE. We surveyed research university students following each major activity using the Assessing Student Perspective of Engagement in Class Tool (ASPECT) survey but did not find a correlation between NOS and activity engagement. Of the three activities, we found the highest engagement with agar art, especially in the CURE developer class. Interviewed students in all classes described agar art as a fun, relevant, and low-stakes assignment. This work contributes to the evidence supporting agar art as a curricular tool, especially in ways that can add research to classrooms in and beyond the research university.