scholarly journals Hidden reservoirs of pathogens in dental settings

2021 ◽  
Vol 17 (1) ◽  
pp. 73-79
Author(s):  
Silpi Chatterjee ◽  
Keyword(s):  
Staphylococcus Aureus ◽  
Mobile Phones ◽  
Nosocomial Infections ◽  
Bacterial Species ◽  
Brain Heart Infusion ◽  
Bacillus Species ◽  
Coagulase Negative Staphylococcus ◽  
Cross Contamination ◽  
Sterile Saline ◽  
Predominant Species

Nosocomial infections are a major concern to both clinicians and health care seekers. Investigations have suggested that laptops & mobile phones may contribute to cross-contamination and can serve as vehicles for infection transmission. Therefore, it is of interest to document the data on hidden reservoirs such as mobile phones and laptops of pathogens in dental settings at the Hazaribag college of dental sciences and Hospital, Jharkhand. The samples were collected from 25 laptops and 25 mobile phones from dentists working in a dental college in Hazaribag city. The samples were collected aseptically using sterile cotton swabs dipped in sterile saline by rotating the swabs on the keyboard surfaces of laptops and mobile phones, inoculated into Brain Heart Infusion broth, vortexed for 1 minute in Fischer Vortex Genie 2 on highest setting & streaked immediately on 5% sheep blood agar plates and were incubated at 370C for 24 hours aerobically. The isolates were identified based on the colony morphology, colony characteristics and biochemical reactions. The bacterial species isolated were Staphylococcus aureus, Coagulase negative Staphylococcus, Bacillus species, Enterococci, Micrococci, and Pseudomonas etc. Predominant species isolated was Staphylococcus aureus and least was Micrococci. Higher percentage of organisms was found at the Department of Periodontics, Endodontics and least was found in Department of Public Health Dentistry. The percentage and type of organism isolated from keyboards of laptops and mobile phones were similar. Thus, laptops and mobile phones act as vehicles for transfer of potential pathogens associated with dental hospitals. Disinfecting the hands prior to examination of patients and disinfection of laptops and mobiles with alcohol wipes should be done to prevent nosocomial infections.

Indoor bacterial pollution, antimicrobial susceptibility patterns and associated risk factors of bacterial isolates among residences of Gondar town, Northwest Ethiopia

2020 ◽  
pp. 1420326X2096337
Author(s):  
Gizeaddis Belay ◽  
Baye Gelaw ◽  
Abiye Tigabu ◽  
R. P. Raju
Keyword(s):  
Risk Factors ◽  
Air Pollution ◽  
Indoor Air ◽  
Indoor Air Pollution ◽  
Bacterial Species ◽  
Bacillus Species ◽  
Coagulase Negative Staphylococcus ◽  
Bacterial Pollution ◽  
Gondar Town ◽  
Associated Risk Factors

Background In Ethiopia, there is not enough information about indoor air bacterial pollution. Therefore, this study aimed to determine bacterial indoor air pollution and its associated risk factors among residences of Gondar town. Methods A cross-sectional survey of indoor air pollution was conducted on 259 selected houses from February to May 2019. Sociodemographic and housing characteristics were collected using a questionnaire and checklist. Passive settle plate method using blood culture media was employed to collect samples and identification of isolates done by both quantitative and qualitative analysis. Results A total of 259 houses were investigated, and 13 different types of bacterial species were isolated. Of these, Bacillus species 259 (100%) and coagulase-negative Staphylococcus species 101 (34.4%), Enterobacter cloacae, Klebsiella species, Citrobacter diversus, Escherichia coli, and Pantoea species were isolates. Tetracycline and cotrimoxazole were ineffective, but ciprofloxacin and ceftriaxone were efficient antibiotics. Educational status, presence of domestic animals within the house, and integrated toilets were significantly associated with indoor bacterial pollution ( p < 0.05). Conclusion Indoor air pollution was higher in this study than international quantification limit (5 colony-forming unit/4 h) of clean rooms. So, periodic surveillance of indoor air quality and assessing risk factors should be addressed to assess the burden and intervene accordingly.

Necrotizing Fasciitis and Methicillin Resistant Staphylococcus Aureus

2018 ◽  
Vol 3 (07) ◽  
Author(s):  
Dr. Rima W. Ninawe ◽  
Dr. Wasudeo Gyanidas Ninawe
Keyword(s):  
Diabetes Mellitus ◽  
Staphylococcus Aureus ◽  
Soft Tissue ◽  
Necrotizing Fasciitis ◽  
Antimicrobial Agents ◽  
Bacillus Species ◽  
Coagulase Negative Staphylococcus ◽  
Acinetobacter Species ◽  
Streptococcus Group ◽  
Male Predominance

Necrotizing fasciitis (NF) is an aggressive and life-threatening infection of skin and soft tissue characterized by widespread fascial necrosis which leads to morbidity and mortality if left untreated. There is difficulty in managing this condition because there is a combination of difficulty in diagnosis, and also of early as well as late management. It can be caused by either a single organism or more frequently by a variety of microbes - both aerobic and anaerobic. Necrotizing fasciitis seems to have preponderance in males, perhaps due to increased incidence of trauma in males. Staphylococcus aureus is the most prevalent pathogen in hospitals and communities and MRSA has become a common isolate associated with skin and soft tissue infections over the past few years, monomicrobial MRSA necrotizing fasciitis has been reported only in a few studies. Early surgical intervention, early diagnosis and aggressive treatment should be done. Material and Methods: All patients were diagnosed as NF on surgical report. Surgical exploration is undertaken after resuscitation. Penicillin along with, an amino glycoside and clindamycin or metronidazole is administered preoperatively in moribund patients. Cefoxitin or imipenem or meropenem is used in more limited infections. Fair amount of desloughing is done without anesthesia. Overlying fat as patchy greenish-black liquefaction necrotic tissues are excised primarily, and specimen sent for culture in microbiology department. Cultures were processed the susceptibility of S. aureus isolates to antimicrobials was done. Results: A total of 200 hospitalized patients those who were surgically treated for NF were included in the study. Of the 200 patients 42 patients were culture positive for MRSA. In our study mean age was 56± 11.21 of which 124 (62%) were male , mean hospitalization days were 16.5± 6.2. patients with underlying diabetes mellitus were 66 (33%) and hypertension were 74(37%). In MRSA group (n=42) mean age was 53 ± 9.22. Male were 36 (73.81%) , mean hospitalization days were 17.6 ± 6.2. patients with underlying diabetes mellitus were 21 (50%) and hypertension were 19(45.24%).42 (21%) were MRSA, 31 (15.5%) were MSSA, 21 (10.5%) were coagulase negative staphylococcus, 4(2%) were Streptococcus group A, 11 (5.5%) were Streptococcus species, 6 (3%) were Bacillus species, 24 (12 %) were Escherichia coli, 19 (9.5%) were Acinetobacter species, 3 (1.5%) were Candida albicans and in 30 (15%) no growth was observed in culture. Discussion and Conclusion: Some experts recommend use of broad-spectrum empirical antimicrobial therapy for suspected cases of necrotizing fasciitis and therapy directed against MRSA is not a standard practice. For treatment selection of appropriate antimicrobial agents for any suspected necrotizing fasciitis must take into account the nature of patient's exposure and local epidemiologic data but no reliable epidemiological or clinical risk factors with MRSA from those infected with MSSA or non-S. aureus are available. In our study mean age of patients diagnosed NF was 53 ± 9.22. While male were 36 (73.81%). In study by Cheng NC et al. the median age was 62 years (range, 12-81 years) There was male predominance in NF by MRSA in our study . In our study lesions on extremities had better prognosis similar results were shown in other study. Necrotizing fasciitis caused by MRSA is a challenge to the treating surgeon. Prompt diagnosis and surgical management with empiric MRSA cover in areas where community acquired MRSA (CA-MRSA) is endemic. Lesions of extremities have better prognosis where MRSA infection is becoming endemic and empirical treatment of suspected necrotizing fasciitis or pneumonia should include active MRSA cover.

scholarly journals Bacteriological Examination of Used Towels from Female and Male Hostel of Federal University of Lafia

2021 ◽  
pp. 28-34
Author(s):  
Naja’atu Shehu Hadi ◽  
UYI, Gerard Osuyi ◽  
Sani Bashir ◽  
Fatima Al-Mustapha Yusuf ◽  
Kabiru Abdullahi Shuaibu ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Bacterial Species ◽  
Clinical Importance ◽  
Coagulase Negative Staphylococcus ◽  
Male And Female ◽  
Warm Environment ◽  
Significant Difference ◽  
High Prevalence ◽  
Identification And Characterization

Bath towels have the ability to retain microbes, moist and warm environment offers microbes a favorable place to grow and survive. These microbes can be transmitted through direct contact with our hands and other inanimate objects within the environment. This study aimed at examining bacterial contamination of used towels. Used towels from male and female hostels at Federal University of Lafia, were assessed to determine their bacterial concentration. A total of sixteen (16) used towels were sampled, eight towels each from female and male hostels were sampled between April and May 2021. Identification and characterization of bacterial isolates was carried out using standard cultural, morphological and biochemical methods. Pseudomonas spp, Staphylococcus aureus, Klebsiella spp, Escherichia coli, Streptococcus, Micrococcus spp, Serratia sp and Coagulase Negative Staphylococcus were identified as contaminants in the towel samples analyzed. The female towels assessed in this study had the highest number of colonies with 4.39 x 109, while the male towels had the least number of colonies 3.88 x 109. Male and female towels sampled were all contaminated, but with no significant difference in the contamination rates (p>0.05). Staphylococcus aureus and coagulase-negative Staphylococcus were the most prevalent organisms isolated from male (62.5%; 5/8) and female (100%; 8/8) towels respectively. The high prevalence of diverse bacterial species is worrisome considering the epidemiology and clinical importance of the isolates, compounded by antimicrobial resistance and high mortality rate. Hence, there is need to enforce and improve hygiene practice among students. Frequent washing of towels and use of medicated soaps and disinfectants in bathing and washing water is hereby canvassed.

scholarly journals The bacterial profile and sensitivity patterns of isolates from medical equipment and surfaces in the Children’s emergency room of a Nigerian hospital

2019 ◽  
Vol 6 (9) ◽  
pp. 192-197
Author(s):  
Ikenna Kingsley Ndu ◽  
Isaac Nwabueze Asinobi ◽  
Uchenna Ekwochi ◽  
Obinna Chukwuebuka Nduagubam ◽  
Ogechukwu Francesca Amadi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Emergency Room ◽  
Nosocomial Infections ◽  
Cross Sectional Study ◽  
University Teaching ◽  
Hospital Environment ◽  
Diffusion Method ◽  
Coagulase Negative Staphylococcus ◽  
Cross Sectional

Objective:  Nosocomial infections are those acquired in hospitals or healthcare service units that first appear 48 hours or more after admission or within 30 days after discharge following in-patient care. Knowledge of the bacterial profile and sensitivity patterns of any hospital environment is a key factor in infection control and good antibiotic stewardship. Material and Methods: This hospital-based cross-sectional study was conducted in the Children’s Emergency Room (CHER) of Enugu State University Teaching Hospital, Enugu, Nigeria.  Samples for culture were collected from equipment and hospital surfaces. Antimicrobial susceptibility testing was determined for each isolate by the Agar diffusion method using Standard Nutrient Agar 1 discs. Results: Bacterial growth was observed in 83 (70.3%) specimens. Staphylococcus aureus (53.4%) was the most common isolate cultured followed by Coagulase-negative Staphylococcus (18.8%), then Escherichia coli (13.9%). Among Staphylococcus aureus isolates, 25.9% were MRSA. Ampicillin resistance of the gram negatives was high. All the Gram-negative isolates were susceptible to Ciprofloxacin and Ceftriaxone. Conclusion: Staphylococcus aureus, Coagulase-negative Staphylococcus, and Escherichia coli were the commonest isolates. More efforts are needed to ensure improved hygiene standards in order to reduce the burden of nosocomial infections.

scholarly journals Epidemiology of bacterial contamination of inert hospital surfaces and equipment in critical and non-critical care units: a Brazilian multicenter study

2019 ◽  
Author(s):  
Dayane Otero Rodrigues ◽  
Laís da Paixão Peixoto ◽  
Erica Tatiane Mourão Barros ◽  
Julianne Rodrigues Guimarães ◽  
Bruna Clemente Gontijo ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Medical Equipment ◽  
Bacterial Contamination ◽  
Bacterial Species ◽  
Brain Heart Infusion ◽  
Multidrug Resistant ◽  
Public Hospitals ◽  
Hospital Environment ◽  
Cross Sectional ◽  
Inert Surfaces

AbstractThe hospital environment is an important reservoir of microorganisms, including multidrug-resistant pathogens, which can cause in-patient contamination and healthcare-related infections. The objective of this study was to analyze the epidemiology of bacterial contamination (contaminated sites, pathogen species and their antimicrobial susceptibility, and tracking of multidrug-resistant microorganisms - MDR) of inert hospital surfaces and medical equipment in two public hospitals in Northern Brazil. This was a cross-sectional study with 243 samples (n = 208, from Hospital A; and n = 35, from Hospital B) collected by friction with swabs moistened in Brain Heart Infusion from inert surfaces and equipment. The samples were cultivated and bacterial species were identified by the classical approach and tested for their susceptibility through agar diffusion assay according to the Clinical and Laboratory Standards Institute (CLSI). Most inert surfaces and equipment analyzed presented bacterial contamination (95.5%). Staphylococcus aureus was the main pathogen of clinical significance detected both in Hospital A (61.8%) and B (68.6%). Hospital A showed higher rates of isolated MDR bacteria than Hospital B, especially in the Adult Intensive Care Unit, which included methicillin-resistant Staphylococcus aureus (MRSA) (52.7%), Enterobacteria resistant to 4th generation cephalosporins (19.4%), and multidrug-resistant Pseudomonas aeruginosa (2.78%). The failures in the prevention and control of infections in the two hospitals analyzed reinforce the need for a revised protocol for cleaning and disinfection of inert surfaces and medical equipment, and for regulation of antibiotic dispensing, mainly in the AICU of Hospital A, which was found to be a reservoir of MDR pathogens. This study is innovative because it is the pioneer in Western Bahia that describes the epidemiology of contamination of hospital surfaces, opportuning futures studies in this field.

scholarly journals The Risk of Nosocomial Infection Transmission in the Paediatric Outpatient Clinic in a Developing Country

2021 ◽  
pp. 92-98
Author(s):  
Ogechukwu F. Amadi ◽  
Awoere T. Chinawa ◽  
Isaac N. Asinobi ◽  
Uchenna Ekwochi ◽  
Obinna C. Nduagubam ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Nosocomial Infection ◽  
Outpatient Clinic ◽  
Nosocomial Infections ◽  
University Teaching ◽  
Diffusion Method ◽  
Coagulase Negative Staphylococcus ◽  
Infection Transmission ◽  
Sensitivity Pattern ◽  
Essential Components

Objective: As more care is provided for children in outpatient facilities, it is increasingly important to understand the potential for disease transmission and this is particularly so for nosocomial infections which are infections originating in hospitals. Knowledge of the profile of bacterial isolates of surfaces in outpatient facilities and their sensitivity patterns serves as a guide for prevention of nosocomial infection transmission. Material and Methods: This hospital-based cross-sectional study was conducted in the Children's Outpatient Clinic (CHOP) of Enugu State University Teaching Hospital, Parklane, Enugu, Nigeria (ESUT-TH). Samples for culture were collected from equipment and hospital surfaces. Antimicrobial susceptibility testing was determined for each isolate by the Agar diffusion method using Standard Nutrient Agar 1 discs. Results: Out of 122 samples collected from various sites, bacterial growth was observed in 55 (45.0%) specimens. Staphylococcus aureus and Coagulase-negative Staphylococcus were the most common isolates cultured from 23 different locations. Among the Staphylococcus aureus isolates, 17.4% (4/23) were MRSA. Levofloxacin and Imipenem showed the best sensitivity pattern for Staphylococcus aureus Conclusion: Staphylococcus aureus, Coagulase-negative Staphylococcus were the commonest isolates. There is need to develop specific protocols that will ensure hand hygiene, judicious use of antimicrobials, active surveillance, and enhanced cleaning/disinfection of surfaces in outpatient clinics as essential components of prevention and control of nosocomial infections.

scholarly journals Indoor bacterial load and its correlation to physical indoor air quality parameters in public primary schools

2019 ◽  
Vol 14 ◽  
Author(s):  
Zewudu Andualem ◽  
Zemichael Gizaw ◽  
Laekemariam Bogale ◽  
Henok Dagne
Keyword(s):  
Staphylococcus Aureus ◽  
Air Quality ◽  
Relative Humidity ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Primary Schools ◽  
Indoor Environment ◽  
Bacterial Load ◽  
Bacillus Species ◽  
Coagulase Negative Staphylococcus

Background: Poor indoor air quality is a great problem in schools due to a high number of students per classroom, insufficient outside air supply, poor construction and maintenance of school buildings. Bacteria in the indoor air environment pose a serious health problem. Determination of bacterial load in the indoor environment is necessary to estimate the health hazard and to create standards for indoor air quality control. This is especially important in such densely populated facilities like schools. Methods: Institutional based cross-sectional study was conducted among 51 randomly selected classrooms of eight public primary schools from March 29–April 26, 2018. To determine the bacterial load passive air sampling settle plate method was used by exposing a Petri dish of blood agar media for an hour. The Pearson correlation matrix was employed to assess the correlation between bacterial load and physical parameters. Results: The grand total mean bacterial load was 2826.35 CFU/m3 in the morning and 4514.63 CFU/m3 in the afternoon. The lowest and highest mean bacterial load was recorded at school 3 (450.67 CFU/m3) and school 5 (7740.57 CFU/m3) in the morning and afternoon, respectively. In the morning relative humidity (r = −0.7034), PM2.5 (r = 0.5723) and PM10 (r = 0.6856); in the afternoon temperature (r = 0.3838), relative humidity (r = − 0.4014) were correlated with indoor bacterial load. Staphylococcus aureus, Coagulase-negative Staphylococcus species and Bacillus species were among isolated bacteria. Conclusions: High bacterial load was found in public primary schools in the Gondar city as compared to different indoor air biological standards. Temperature, relative humidity and particulate matter concentration (PM2.5 and PM10) were associated with the indoor bacterial load. Staphylococcus aureus, Coagulase-negative Staphylococcus species and Bacillus species were among isolated bacterial species. Attention should be given to control those physical factors which favour the growth and multiplication of bacteria in the indoor environment of classrooms to safeguard the health of students and teachers in school.

scholarly journals The Inhibition Potentials of Different Honey against Staphylococcus aureus, Escherichia coli and Bacillus species Isolated from Clinical Source

2020 ◽  
pp. 46-55
Author(s):  
Akani, Nedie Patience ◽  
Amadi Wemedo, Samuel ◽  
Njoku, Onyedikachi Egbuchulem
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Bacillus Cereus ◽  
Pathogenic Bacteria ◽  
Inhibition Efficiency ◽  
Minimum Bactericidal Concentration ◽  
Bacterial Species ◽  
Diffusion Method ◽  
Bacillus Species ◽  
Clinical Source

As a result of the increased prevalence of antibiotic resistance among different bacteria, different plants and other natural products have been studied and found to be highly effective against pathogenic bacteria. Honey, over the years has been used as an antibacterial agent to treat certain infections caused by bacteria and is believed to be effective especially in rural areas. This study was thus aimed at comparing the effect of different honey samples against some pathogenic bacteria (Escherichia coli, Staphylococcus aureus and Bacillus cereus) isolated from clinical source. This study was carried out in the microbiology laboratory, department of microbiology Rivers State University Nigeria from January 2018 to August 2019. The antibacterial sensitivity test was carried out using agar well diffusion method while the Minimum inhibitory concentration and Minimum bactericidal concentration were determined using broth tube micro dilution technique in two fold dilution. The inhibition efficiency of the honey samples on the test organisms increased with increasing concentration from 20 to 100% as 100% concentration had the highest zone of inhibition. Staphylococcus aureus (6.33 mm – 26.33 mm) was the most sensitive to the honey samples while Bacillus cereus (0.00 – 19.67 mm) was less sensitive. At concentrations of 20 – 80%, raw and Rowse honey were more effective on E. coli compared to Princenic Global honey, while at 100%, Princenic Global honey was more effective on Staphylococcus aureus. Raw and Rowse honey were more effective at 20 -60% concentrations followed by Princenic Global honey; whereas at 80 -100% concentrations, Raw and Princenic Global honey were more effective. Bacillus cereus was resistancet to the honey samples at 20 – 60% but sensitive at 80 – 100% concentrations to Rowse, Raw and Princenic Global honey. The inhibition efficiency of the honey samples on the growth of the tested organisms was found to be dependent on the concentration and type of honey used, as well as they type of organism tested. The result of the minimum inhibitory and minimum bactericidal concentration showed that Staphylococcus aureus was inhibited most at a lower concentration of 25% compared to other bacteria isolates. All honey samples tested did not show any bactericidal effect but was bacteriostatic to some of the tested organisms. Pharmacological standardization and clinical evaluation on the effect of honey is essential before honey can be used as a preventive and curative measure to common diseases related to the tested bacterial species.

scholarly journals Bacterial and Parasitic Assessment from Fingernails in Debre Markos, Northwest Ethiopia

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Abeba Mengist ◽  
Yibeltal Aschale ◽  
Alemayehu Reta
Keyword(s):  
Staphylococcus Aureus ◽  
Intestinal Parasites ◽  
Bacterial Species ◽  
Food Poisoning ◽  
Positive Culture ◽  
Diffusion Method ◽  
Coagulase Negative Staphylococcus ◽  
Food Handlers ◽  
Finger Nail ◽  
Debre Markos

Background. Food handlers with untrimmed finger nails could contribute or serve as a vehicle for the transmission of food poisoning pathogens. Objectives. This study was conducted to determine the prevalence of bacteria and intestinal parasites among food handlers and antibiotic susceptibility profile of the isolated bacteria in Debre Markos University, Ethiopia. Materials and Methods. This laboratory-based cross-sectional study involved 220 food handlers working in food service establishments in Debre Markos University between 1st January 2015 to 31th June 2016. Subjects’ finger nail specimens of both hands were examined microscopically for intestinal parasites. For bacterial isolation, samples were cultured and bacterial species were identified following standard laboratory procedures. Antimicrobial susceptibility test was performed for all bacterial isolates by using Kirby-Bauer disk diffusion method. Results. Of the total 220 subjects examined, 29.5% showed positive culture for different bacterial species from their fingernail contents. Coagulase-negative Staphylococcus was the predominant bacteria species (12.3%) followed by Staphylococcus aureus (5%), E. coli (2.7%), Klebsiella species (2.7%), Enterococcus species (1.8%), Pseudomonas aeruginosa (1.8%), Proteus species (1.4%), Citrobacter species (1.4%), and Serratia species (0.9%). None of the food handlers showed positive culture for Shigella and salmonella and parasites in respect of their finger nail specimens. Isolation of bacteria in finger nail has significant association with finger nail status (P=0.044) and inverse relation with service years (P=0.048). All Staphylococcus aureus and coagulase-negative Staphylococcus species isolates were uniformly susceptible to vancomycin. Only one (9.1%) of Staphylococcus aureus isolates was resistant for methicillin. Conclusion. To prevent the food poisoning pathogens, implementation and adherence to infection are the key practices, specially food handlers with long finger nail harbor food debris, microbial contaminations, and allergens.

scholarly journals Metabolic profiling reveals nutrient preferences during carbon utilization in Bacillus species

2020 ◽  
Author(s):  
James D. Chang ◽  
Ellen E. Vaughan ◽  
Carmen Gu Liu ◽  
Joseph W. Jelinski ◽  
Austen L. Terwilliger ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Bacillus Species ◽  
Ecological Niches ◽  
Phenotype Microarray ◽  
Human Pathogens ◽  
Carbon Utilization ◽  
Reducing Equivalents

AbstractPathogenic bacteria take host nutrients to support their growth, division, survival, and pathogenesis. The genus Bacillus includes species with diverse natural histories, including free-living nonpathogenic heterotrophs such as B. subtilis and host-dependent pathogens such as B. anthracis (the etiological agent of the disease anthrax) and B. cereus, a cause of food poisoning. Although highly similar genotypically, the ecological niches of these three species are mutually exclusive, which raises the untested hypothesis that their metabolism has speciated along a nutritional tract. Here, we employed a quantitative measurement of the number of reducing equivalents as a function of growth on hundreds of different sources of carbon to gauge the “culinary preferences” of three distinct Bacillus species, and related Staphylococcus aureus. We show that each species had widely varying metabolic ability to utilize diverse sources of carbon that correlated to their ecological niches. In addition, carbohydrates are shown to be the preferred sources of carbon when grown under ideal in vitro conditions. Rather unexpectedly, these metabolic utilizations did not correspond one-to-one with an increase in biomass, which brings to question what cellular activity should be considered productive when it comes to virulence. Finally, we applied this system to the growth and survival of B. anthracis in a blood-based environment and find that amino acids become the preferred source of energy while demonstrating the possibility of applying this approach to identifying xenobiotics or host compounds that can promote or interfere with bacterial metabolism during infection.Author summarySuccessful organisms must make nutritional adaptations to thrive in their environment. Bacterial pathogens are no exception, having evolved for survival inside their hosts. The host combats these pathogens by depriving them of potential biochemical resources, termed nutritional immunity. This places pathogens under pressure to utilize their resources efficiently and strategically, and their metabolism must in turn be tailored for this situation. In this study, we examined the carbon metabolism of three human pathogens of varying virulence (Bacillus anthracis, Bacillus cereus, and Staphylococcus aureus) and one nonpathogenic Bacillus (Bacillus subtilis) via a phenotype microarray that senses reducing equivalents produced during metabolism. Our analysis shows the existence of distinct preferences by these pathogens towards only a select few carbohydrates and implies reliance on specific metabolic pathways. These metabolic signatures obtained could be distinguished from one bacterial species to another, and we conclude that nutrient preferences offer a new perspective into investigating how pathogens can thrive during infection despite host-induced starvation.

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