Mean Colony Count Research Articles

Incidence and Antibiotic Resistance Patterns of Staphylococcus aureus and Pseudomonas aeruginosa Isolated from Fomites in Critical Units of General Hospital Katsina

Study’s Excerpt Investigation of the role of fomites in the transmission of nosocomial pathogens, specifically Staphylococcus aureus and Pseudomonas aeruginosa, within various units of General Hospital Katsina was carried out. The results reveal high contamination of fomites in the male ward, with significant bacterial colony counts, and the differing susceptibility profiles of S. aureus and P. aeruginosa to commonly used antibiotics. There is need for improved infection control and antibiotic stewardship in the region. Full Abstract Nosocomial infections, predominantly caused by Staphylococcus aureus and Pseudomonas aeruginosa, continue to be a major public health challenge, especially in developing countries, due to their associated morbidity and mortality. This study aimed to isolate and identify bacterial pathogens from fomites in the Accident and Emergency (A&E) unit, male ward, and female ward of General Hospital Katsina and to evaluate their antimicrobial susceptibility patterns. A total of 90 swab samples were collected from frequently touched items such as beddings, door handles, floor surfaces, scissors, and forceps across the three locations. Standard microbiological techniques were utilized for the isolation and identification of S. aureus and P. aeruginosa, followed by antibacterial susceptibility testing using the disc diffusion method. Bacterial growth was observed in 58 (64.4%) samples, with S. aureus accounting for 32 (55.2%) and P. aeruginosa for 26 (44.8%) of the isolates. The male ward exhibited the highest contamination levels, with a mean colony count of 725.25 CFU/plate, significantly higher than the female ward (487.67 CFU/plate) and the A&E unit (48 CFU/plate), as confirmed by a one-way ANOVA (p < 0.05). Chi-square analysis revealed no statistically significant association between bacterial species and hospital location (p = 0.823). The susceptibility testing showed that S. aureus isolates were generally susceptible to Gentamycin, Ciprofloxacin, and Pefloxacin but resistant to Amoxicillin. Conversely, P. aeruginosa displayed high resistance to Gentamycin and Septrin. Conclusively, these findings revealed the critical role of fomites in the transmission of pathogens and highlighted the need for enhanced infection control measures and targeted antibiotic stewardship programs to mitigate the risks associated with these infections.

Filtered handheld far-ultraviolet disinfection device in reducing environmental pathogens from high-touch clinical surfaces

Background: Healthcare-acquired infections (HAIs) continue to be a major challenge. In fact, an increased risk of HAIs has been linked to high-touch surfaces contaminated with multidrug-resistant organisms (MDROs), and enhanced environmental disinfection is linked to reduced HAI rates. Recently, more focus has been placed on emerging disinfection technologies, such as UV light-producing portable device that emits light at a wavelength of 222 nm, which has previously demonstrated germicidal capabilities at short contact times. In this study, we aim i) to evaluate the efficacy of a filtered far-UV-C handheld device (FFUHH) to reduce bacterial loads on high-touch surfaces in clinical workrooms in a cancer center, and ii) to isolate, identify and establish a genetic relationship between these environmental clinically significant pathogens and the ones recovered from patients. Methods: Samples were collected weekly on a rotating schedule over a 24-week period from five high-touch items (dictation device, mouse, armchair, desk, and keyboard) in multiple clinical work rooms on hematologic malignancy and stem cell transplant units. Contact plates for colony count and swabs were collected pre- and post-intervention with the FFUHH on standardized adjacent areas respectively for each surface. The swabs were enriched and cultured on selective media to isolate clinically significant pathogens. Whole genome sequencing (WGS) was then performed on environmental pathogens validated by MALDI-TOF as well as clinical samples collected from patients in the same unit around the time of environmental sample collection. Results: A total of 440 plates, 220 pre- and 220 post-interventions, were collected and analyzed. The highest mean colony count pre-treatment was detected from the armchairs and the lowest for the keyboards. The mean reduction of colony forming units (CFUs) ranged between 53% for the keyboard and 83% for the mouse. The reduction was statistically significant across all surfaces with P values < 0.05, except for the keyboard (Figure 1). We isolated many pathogens of the human microbiota identified by MALDI-TOF such as Micrococcus luteus, S. capitis as well as methicillin-resistant S. epidermidis, S. haemolyticus and S. hominis. We also identified several Candida parapsilosis, Pseudomonas stutzeri, one Listeria grayi and one Acinetobacter baumanni. Finally, WSG allowed us to further characterize an environmental multi-drug resistant S. epidermidis ST5 strain associated with patient bacteremia, and ST16 strains detected on surfaces both pre- and post-FFUHH treatment. Conclusion: The FFUHH effectively reduced the microbial burden on high-touch surfaces in clinical workrooms on hematologic malignancy and stem cell units.

Molecular Identification of Potent Chromium Reducing Bacteria Isolated from Hydrocarbon-Contaminated Soil within Sokoto Metropolis

Study’s Novelty/Excerpt This study investigates chromium reduction potential of bacteria isolated from hydrocarbon-contaminated soils in the Sokoto metropolis, a specific environment previously underexplored in this context. It uniquely identifies Brucella intermedia and Bacillus sp. as potent chromium-tolerant isolates with significant reduction efficiencies, providing new insights into the bioremediation capabilities of these strains. Additionally, the research demonstrates a high chromium removal efficacy at various concentrations, highlighting the potential application of these isolates for effective bioremediation of chromium-polluted soils and water bodies. Full Abstract Hydrocarbon-contaminated soils are recognised as reservoirs for heavy metal-utilizing bacteria due to the phenomenon of co-selection. These bacteria can have a potential in the biosorption of chromium heavy metal. This research aimed to screen the chromium reduction potential of bacteria isolated from hydrocarbon-contaminated soils. The soil samples used in this study were collected from hydrocarbon-affected sites in the Sokoto metropolis; additionally, a control sample was collected from non-polluted soil. Bacteria were isolated using standard protocols. Variable amounts of chromium were prepared using potassium monochromate (K2CrO4) and then incorporated into a nutrient broth medium. The most potent, molecularly-identified hydrocarbonoclastic bacteria were screened for chromium tolerance, and the percentage reduction in chromium content was also measured. Mean colony counts from the hydrocarbon-contaminated soil ranged from1.00×106 to 1.30×106 CFU/g while the control soil had 2.30×105 CFU/g. From the 14 strains, two, molecularly identified using NCBI BLAST as Brucellaintermedia and Bacillus sp., were shown to be the most potent chromium tolerant isolates. B. intermedia reduced Cr from an initial value of 350 mg/L to 198 mg/L within 72 hours (44 % removal efficiency). At the lowest concentration used in this study (50 mg/L), a removal efficacy of 96% was achieved. Bacillus sp. recorded the highest chromium reduction compared to Brucellaintermedia at the tested concentrations (50, 150, 250, and 350 mg/L). A 100% reduction in Cr was obtained at the 50 mg/L concentration. This study demonstrated that Bacillus sp. and Brucellaintermedia are particularly effective at reducing chromium from chromium metal solutions of different concentrations. These isolates can be used for bioremediation of chromium-polluted soils or water bodies.

Identification of Bacterial Composition of the Nostrils of Primary School Children; Case Study of FUDMA Staff School, Dutsin-Ma, Katsina State

The nasal microbiome consists of a diverse community of microorganisms, with bacteria which are essential for maintaining nasal and respiratory health. This research work aimed at identifying the bacterial composition of the nostrils of primary school-aged children at Federal University Dustin-Ma; staff School, Dutsin-Ma, Katsina, Nigeria. Sterile swab sticks were used to collect 25 samples of each male and female primary school children enrolled at FUDMA Staff School. The samples were then transported to the Department of Microbiology of FUDMA for analysis. Standard laboratory techniques were used for the isolation and identification of the organisms. Results revealed that all samples collected had three main bacterial species which include: Staphylococcus spp. 46(92%), Streptococcus spp. 37(74%), and Corynebacterium spp. 7(14%). Demographic factors like age and gender slightly affect bacterial composition. Children aged 8-10 had the highest bacterial colony counts, likely due to differences in personal hygiene, with males showing a slightly higher bacterial presence. Children exposed to smoke and household pets had higher colony counts of 103 and 96CFU/ml respectively than those not exposed. Additionally, the sources of drinking water all showed different profiles, well water had the highest mean colony count of 98CFU/ml and Borehole water had the lowest mean colony count of 66CFU/ml. The research highlights the importance of understanding the bacterial composition of the nasal microbiome in children. Hence, there is a need to create proper awareness among the general populace on the effects of the factors that influence the nascent nasal microbiome of nostrils among primary school children.

Comparative evaluation of the efficacy of 1% and 3% Sodium hypochlorite in reducing the microbial counts in primary teeth root canals using Bioluminometer – A randomized clinical trial

PurposeSodium hypochlorite (NaOCl) is commonly used to irrigate primary teeth during pulpectomy. Although high concentrations of NaOCl are effective, they pose a risk of toxic damage to periapical tissues if NaOCl penetrates through the apical foramen. Therefore, low concentrations of NaOCl are preferred to mitigate this risk. However, concerns persist regarding the antibacterial efficacy of low concentrations of NaOCl compared to high concentrations. The objective of this study was to assess and compare the efficacy of 1% and 3% NaOCl irrigation in reducing bacterial load within primary teeth root canals. Materials and methodsThis clinical study involved forty participants divided into two groups. Group 1 (n = 20) received canal irrigation with 1 % NaOCl solution, while Group 2 (n = 20) received canal irrigation with 3 % NaOCl solution. Microbial samples were collected from the root canal using a paper point before and after irrigation. The samples were aseptically transferred to ultra-snap tubes and then analyzed using a Bioluminometer. The results were recorded. ResultsBoth groups exhibited a decrease in bacterial count after irrigation. The mean colony count post irrigation for 3 % NaOCl was 258.05 ± 28.61, and for 1 % NaOCl it was 267.60 ± 30.56. However, no statistically significant difference was observed upon intergroup comparison. ConclusionThis study shows that 1% NaOCl is equally effective as 3% NaOCl in reducing bacterial count in root canals. Thus, using 1% NaOCl as an irrigant is appropriate in clinical practice.

Potential of cassava peel collected from Bauchi (Nigeria) as culture media for growing specific fungi

The objective of this paper is to assess the potential of using cassava peel for A. niger and penicillium growth using standard methods and chemicals of analytical grade. The result of the study indicates that, the peel is rich in proximate contents as the analyzed cassava peel is composed of 8.70% moisture, 4.89% crude protein, 6.9.00% carbohydrates, 4.00 % fat content, 8.93% ash, and 8.75% fibre. Considering the observed morphological and physical characteristics of the test fungi; therewith, A. niger, and penicillium were present. There is indication that, the two utilized media (control and formulated media) are in support of the two microbes growth and depicted positive results of degradation, as well as fermentation ability on the cassava peels. The enriched cassava agar supports higher growth of the two analyzed microbes (viz, A. niger, and penicillium). There was significant difference pertaining the colonies number made on the formulated media (cassava peel agar, and enriched cassava agar). Potato dextrose agar (PDA) shows lower colony count amounting to 3.4 0.1 CFU/ml for A. niger, and amounting to 3.3 0.2 CFU/ml for penicillium. Cassava peel agar (CPA) possessed 6.5 0.5 CFU/ml mean colony count (MCC) for A. niger, and 5.6 0.1 CFU/ml for penicillium. Enriched cassava agar media (ECA) had highest MCC as 7.8 0.1 CFU/ml with respect to A. niger, and 7.3 0.6 CFU/ml pertaining penicillium. Utilization of cassava peel as substrate due to its contents of nutrients that can meet the nutritional requirement of fungi growth is a better move. The peel may be considered as substitute and alternative substrate for producing culture media to cultivate fungi and consequently reducing pollution.

Integrating computational and experimental chemical biology revealed variable anticancer activities of phosphodiesterase isoenzyme 5 inhibitors (PDE5i) in lung cancer.

Phosphodiesterase 5 (PDE5), an enzyme responsible for catalyzing the degradation of cyclic guanosine monophosphate (cGMP), has been linked to the development of cancer. PDE5 inhibitors (PDE5i), such as sildenafil (Viagra) and tadalafil (Cialis), work by blocking the action of PDE5 and are used primarily as treatments for erectile dysfunction and arterial hypertension. Some studies suggested a potential link between PDE5i and increased cancer risk, while other studies showed preferable antitumor effects. The present study is attempting to shed light on the systems biology effects of PDE5i by applying an integrative informatics approach followed by experimental validation methods including cell viability, cell motility, and proliferation capacity. Cell cycle and apoptosis analyses were carried out using flow cytometry, while real-time polymerase chain reaction (PCR) and western blotting were used to determine the relative gene and protein expression respectively. Our results indicated that the examined PDE5i significantly inhibited the proliferation of lung cancer cells, in addition to reducing wound closure and the mean colony count and size. Furthermore, PDE5i increased the early and late apoptotic activities and suppressed the gene and protein expression of PDE5 in lung cancer cells. The combination of cisplatin and raloxifene with PDE5i resulted in a synergistic effect. This study provides solid evidence supporting the anti-tumorigenic effect of PDE5i in lung cancer cells.

In Vitro Assessment of the Effects of Varying Dosages of Alexandrite Laser on the Development of Staphylococcus Aureus

Background: This study aimed to apply a high-power pulsed alexandrite laser in vitro, the researchers tested different exposure periods, pulse lengths, and laser fluencies to see which dosage was most successful against S. aureus bacteria, which had developed resistance to many antibiotics. Method: Three bacteria samples were exposed to laser beams for 30 seconds with a 5ms pulse duration and a laser fluency of 5J/cm2. The process was repeated with laser fluencies of 10, 15, and 20. Results: The study was carried out by using different doses of Alexandrite laser. Results: There are significant differences (p = 0.05) in the mean number of bacteria colonies exposed for 30 and 60 seconds at any laser fluencies utilized in the present investigation. Except for the 15 J.cm-2 laser fluency; there was a statistically significant difference (p < 0.001) between 60 sec and 90-sec exposure durations. Conclusion: In conclusion, the exposure periods, pulse durations, and laser fluencies of pulsed alexandrite laser were found to have an influence on the mean colony count of S aureus bacteria and to establish the effective dose.

Efficacy of a filtered far-UVC handheld disinfection device in reducing the microbial bioburden of hospital surfaces

The filtered far-UV-C (FFUV) handheld disinfection device is a small portable device that emits far UV-C at 222nm. The objective of this study was to evaluate the device's ability to kill microbial pathogens on hospital surfaces and compare it to manual disinfection using germicidal sodium hypochlorite wipes. A total of 344 observations (4 observations from 86 objects' surfaces) were sampled with 2 paired samples per surface: a pre- and a post-sodium hypochlorite and FFUV sample. The results were analyzed via a Bayesian multilevel negative binomial regression model. The estimated mean colony counts for the sodium hypochlorite control and treatment groups were 20.5 (95% uncertainty interval:11.7-36.0) and 0.1 (0.0-0.2) colony forming units (CFUs), respectively. The FFUV control and treatment groups had mean colony counts of 22.2 (12.5-40.1) and 4.1 (2.3-7.2) CFUs. The sodium hypochlorite group and the FFUV group had an estimated 99.4% (99.0%-99.7%) and 81.4% (76.2%-85.7%) reduction in colony counts, respectively. The FFUV handheld device effectively reduced the microbial bioburden on surfaces in the health care setting. The major benefit of FFUV is likely seen when manual disinfection is not possible or when supplementing cleaners or disinfectants with the low-level disinfection properties.

Comparative evaluation of the antibacterial efficacy of a bioactive material enhanced by phytosynthesized nanoparticles: An in vitro study

ABSTRACT Aim: To evaluate and compare the antibacterial efficacy of ACTIVA Bioactive base/liner (ABBL) enhanced with phytosynthesized titanium dioxide nano-particles (nTiO2) and nano-curcumin (nCur). Methods: nTiO2 (3%) was phytosynthesized from moringa leaves extract and characterized. nCur (7%) was synthesized from Curcumin taken in dichloromethane and sprayed into boiling water. Metal molds with a diameter of 5 mm were placed on a glass slab and filled with ABBL (Group 1) and cured. For Group 2 (ABBL + nTiO2), 3% phytosynthesized titanium dioxide (TiO2) was added to ABBL and cured. For Group 3 (ABBL + nCur), ABBL discs were fabricated and 7% nCur was surface-coated on these discs and cured. Seven samples for each group with a total sample size of 42 specimens were assessed for anti-biofilm efficacy against Streptococcus mutans at the end of 1 day and 7 days and expressed in colony forming units. Intergroup and intragroup comparison of colony counts was assessed using the one-way analysis of variance and paired t-test, respectively. Level of significance was set at 0.05. Results: Intergroup comparison on day 1 and 7 showed significant difference (P = 0.016/P = 0.002) amongst the test groups, where Groups 3 and 1 showed maximum increase in bacterial colonies, respectively, and Group 2 showed minimum. On intragroup comparison, all groups showed an increase in mean colony counts from day 1 to 7, with significant difference only in Group 1 (P = 0.004). Conclusion: ABBL + 3% TiO2 showed superior results. The antibacterial activity of ABBL decreased with time whereas, ABBL + 7% nCur showed sustained release during the tested time.

Detection of Opportunistic Fungi from the Bronchoalveolar Lavage Specimens of Patients with Pulmonary Diseases.

Opportunistic fungi are a constantly evolving group of pathogens that become active when the immune system is compromised, begin to multiply, and soon overwhelm the weakened immune system. This study was performed to evaluate the number of opportunistic fungi in bronchoalveolar lavage (BAL) samples of patients with pulmonary diseases. After receiving patients' consent and demographic forms, a total of 120 BAL samples were taken by a pulmonary physician. The etiologic agents were identified by standard morphological and molecular methods. Yeast cells were counted on culture media, and direct smears were precisely examined for the presence of yeasts elements, Pneumocystis, and filamentous fungi. In this study, 29 (24.1%) patients showed positive direct smears for yeast elements in their BAL samples. The mean colony count of yeasts was 42,000 (CFU/mL) on culture media. Six (5%) species of filamentous fungi, including three (2.5%) isolates of Penicillium species (P. variabile, P. glabrum, and P. thomii), two (1.67%) Aspergillus species (A. flavus and A. fumigatus), 1 case (0.83%) Pseudallescheria boydii were detected. Seven cases (5.83%) of Pneumocystis cysts were observed in the direct smears stained with Giemsa. Identification of all fungi confirmed by molecular or sequencing methods. Due to the presence of a large number of fungi in the BAL samples and possible physical interference with the selected drugs for treatment, we draw the attention of pulmonologists to this important issue. Rapid diagnosis of fungal infections is essential to optimize treatments and outcomes.

Assessment of microbial bioburden on portable medical equipment in a hospital setting.

Although routine disinfection of portable medical equipment is required in most hospitals, frontline staff may not be able to disinfect portable medical equipment at a rate that adequately maintains low bioburden on high-use equipment. This study quantified bioburden over an extended time period for two types of portable medical equipment, workstations on wheels and vitals machines, across three hospital wards. Bioburden was quantified via press plate samples taken from high touch surfaces on 10 workstations on wheels and 5 vitals machines on each of 3 medical surgical units. The samples were taken at three timepoints each day over a 4-week period, with random rotation of timepoints and portable medical equipment, such that frontline staff were not aware at which timepoint their portable medical equipment would be sampled. The mean bioburden from the different locations and portable medical equipment was estimated and compared with Bayesian multilevel negative binomial regression models. Model estimated mean colony counts (95% credible interval) were 14.4 (7.7-26.7) for vitals machines and 29.2 (16.1-51.1) for workstations on wheels. For the workstations on wheel, colony counts were lower on the mouse, 0.22 (0.16-0.29), tray, 0.29 (0.22, 0.38), and keyboard, 0.43 (0.32-0.55), when compared to the arm, as assessed by incident rate ratios. Although routine disinfection is required, bioburden is still present across portable medical equipment on a variety of surfaces. The difference in bioburden levels among surfaces likely reflects differences in touch patterns for the different portable medical equipment and surfaces on the portable medical equipment. Although the association of portable medical equipment bioburden to healthcare-associated infection transmission was not assessed, this study provides evidence for the potential of portable medical equipment as a vector for healthcare-associated infection transmission despite hospital disinfection requirements.

Antimicrobial properties of glass-ionomer cement incorporated with zinc oxide nanoparticles against mutans streptococci and lactobacilli under orthodontic bands: An in vivo split-mouth study

Background: The aim of this study was to assess the effect of incorporation of zinc oxide nanoparticles (ZnO-NPs) to glass-ionomer cement (GIC) (Fuji II SC, GC Corp., Tokyo, Japan) on subgingival accumulation of mutans streptococci and lactobacilli under orthodontic bands.Materials and Methods: In order to conduct this in vivo split-mouth study, 20 patients aged between 7 and 10 years who required lingual holding arch on their mandibular first molars were divided into two groups. In one group, Fuji II SC GIC was used for cementation of the right molar band, and the same cement containing 2 wt% ZnO-NPs was used for the left one. The opposite was performed for the second group while the operator was blinded to the cement types. Subgingival microbial sampling was performed 16 weeks after cementation of lingual arch. Mutans streptococci and lactobacilli colony counts were compared. Paired t-test was used to compare the two cement groups. Data were analyzed using SPSS version 21, and P ≤ 0.05 was considered statistically significant.Results: The mean colony counts of mutans streptococci, lactobacilli, and total bacterial count in Fuji II SC containing ZnO-NPs were significantly lower than the corresponding values in plain Fuji II SC group.Conclusion: Incorporation of ZnO-NPs into GIC reveals antimicrobial features against mutans streptococci and lactobacilli under orthodontic bands.

In Vitro Effect of a High-Intensity Laser on Candida albicans Colony Count.

Introduction: This study assessed the effect of a high-intensity laser on Candida albicans colony count. Methods: This in vitro, experimental study was conducted on standard-strain C. albicans (ATCC18804). Seventy-two samples with two different concentrations of C. albicans (104 cells/mL and 106 cells/mL) were randomly assigned to three groups of control, laser and nystatin. Each group included 12 samples from each concentration. In the nystatin group, 10 cc of nystatin suspension was added to the samples and mixed for 30-60 seconds. In the laser group, the Ga-Al-Ar diode laser with a 940-nm wavelength and 2-W power was irradiated to the samples with 0.4 mm tip diameter in non-contact mode (1-mm distance) at a speed of 1 mm/s. The suspensions in the three groups were cultured on the Sabouraud dextrose agar culture medium and incubated at 37°C for 24 hours. The number of C. albicans colonies was then counted and reported. The three groups were compared by ANOVA and Tukey's test (alpha=0.05). Results: In both concentrations, the mean colony count in the nystatin group was significantly lower than that in the control (P<0.05) and laser (P<0.05) groups. The mean colony count in the laser group was significantly lower than that in the control group (P<0.05). Conclusion: The high-intensity laser with a 940-nm wavelength and 2-W power in non-contact mode can significantly decrease the C. albicans colony count in vitro, but its effect is lower than that of nystatin.

Molecular surveillance of non-O157 Shiga toxigenic Escherichia coli in selected chicken abattoirs and retail outlets in Osogbo, Osun State, Nigeria

Three selected chicken abattoirs and two retail locations were studied to determine the frequency of occurrence and profile for Shiga toxin-producing Escherichia coli (STEC) strains present in abattoirs and retail (frozen) chicken carcasses in Osun state, Nigeria. Samples were plated on Eosin Methylene Blue agar for the presence of E. coli. Furthermore, the isolates were confirmed serologically as non-O157 STEC using latex agglutination serotyping kit. Multiplex PCR was used to check for specific virulence factors in the isolated E. coli strains. The mean colony count results showed that effluent water samples from the Ikirun slaughter slab type abattoir were the highest at 25 cfu/ml. A post hoc comparison showed that this value was significantly higher than that of the slaughtering table at Oluode-1 (P = 0.04) and retail chicken meat samples at Igbona (P = 0.01). The results show that chicken abattoirs are poor reservoirs of STEC. Moreover, the results from this study showing that the stx2-producing strains that are more prone to cause hemolytic uremic syndrome is the predominant strain in the study area is worrisome. These results underscore the improper hygiene practices of the abattoir workers combined with inadequate waste management and biological waste disposal systems. It is recommended that regulatory bodies in this locality should focus on ensuring the upgrade of biological waste disposal from these abattoirs in order to limit spread of potentially virulent pathogens into the runoff and ground water.

The evaluation of electrolyzed water, sodium dichloroisocyanurate, and peracetic acid with hydrogen peroxide for the disinfection of patient room surfaces

Sporicidal disinfectants are necessary to control Clostridioides difficile and Candida auris. Novel application methods such as electrostatic sprayers may increase disinfection effectiveness. We employed a standardized protocol to assess 3 sporicidal disinfectants: electrolyzed water (EW), sodium dichloroisocyanurate (NaDCC) and peracetic acid/hydrogen peroxide (PAA/H2O2). The study was conducted at 2 New York City hospitals (1,082 total beds) over an 18-month period. The 3 chemicals were applied by housekeeping personnel following the hospital protocol; the use of electrostatic sprayers was incorporated into EW and NaDCC. In randomly selected rooms, 5 surfaces were sampled for microbial colony counts after cleaning. Data analyses were performed using negative binomial logistic regression. We collected 774 samples. NaDCC-disinfected surfaces had a lower mean colony count (14 colony forming units [CFU]) compared to PAA/H2O2 (18 CFU, P=.36) and EW (37 CFU, P < .001). PAA/H2O2 and EW had more samples with any growth (both P < .05) compared to NaDCC. NaDCC applied with wipes and an electrostatic sprayer had the lowest number of samples with no growth and <2.5 CFU/cm2 (difference not significant). The use of NaDCC for surface disinfection resulted in the lowest bacterial colony counts on patient room high touch surfaces in our study.

Longitudinal Assessment of Contamination Patterns on Workstations on Wheels (WOWs)

Background Representations of contamination on portable medical equipment inform strategies to prevent transmission and healthcare-associated infections (HAIs). While periodic disinfection of equipment is required in most hospitals, the complexity of demands on staff may limit their ability to adequately disinfect multiple surfaces and touch points on a piece of equipment. The purpose of this study was to determine if current disinfection practices were effectively managing bioburden on WOWs on our hospital wards. Methods Samples were collected using press plate for four weeks from 10 WOWs on three medical-surgical units in our hospital. The sampling scheme limited the ability of staff to anticipate sampling and ensured multiple surfaces on each WOW were consistently sampled. Aerobic bacterial colony counts were calculated after 24 hours of incubation. Bayesian multilevel models estimated the mean bioburden and compared bioburden from different locations on WOWs. Results Out of the 452 samples, the estimated mean colony count (95% credible interval) was 29.2 (16.1-51.1). The incident risk-ratio comparing the handle to the other surfaces on the WOWs were 0.43 (0.32-0.55) for the keyboard, 0.29 (0.22-0.38) for the tray, and 0.22 (0.16-0.29) for the mouse. Conclusions The handle used for moving the WOW around, had greater bioburden compared to the keyboard, tray, or the mouse. Difference in the bioburden may reflect number of touches and lack of hand hygiene when moving equipment. The lower bioburden on keyboards and mouses may conversely reflect greater attention to hand hygiene or may be an artifact of sampling (less contact with press plates). The correlation of bioburden to HAI transmission was not studied here so the significance of bioburden alone in the absence of HAI monitoring is uncertain. Representations of contamination on portable medical equipment inform strategies to prevent transmission and healthcare-associated infections (HAIs). While periodic disinfection of equipment is required in most hospitals, the complexity of demands on staff may limit their ability to adequately disinfect multiple surfaces and touch points on a piece of equipment. The purpose of this study was to determine if current disinfection practices were effectively managing bioburden on WOWs on our hospital wards. Samples were collected using press plate for four weeks from 10 WOWs on three medical-surgical units in our hospital. The sampling scheme limited the ability of staff to anticipate sampling and ensured multiple surfaces on each WOW were consistently sampled. Aerobic bacterial colony counts were calculated after 24 hours of incubation. Bayesian multilevel models estimated the mean bioburden and compared bioburden from different locations on WOWs. Out of the 452 samples, the estimated mean colony count (95% credible interval) was 29.2 (16.1-51.1). The incident risk-ratio comparing the handle to the other surfaces on the WOWs were 0.43 (0.32-0.55) for the keyboard, 0.29 (0.22-0.38) for the tray, and 0.22 (0.16-0.29) for the mouse. The handle used for moving the WOW around, had greater bioburden compared to the keyboard, tray, or the mouse. Difference in the bioburden may reflect number of touches and lack of hand hygiene when moving equipment. The lower bioburden on keyboards and mouses may conversely reflect greater attention to hand hygiene or may be an artifact of sampling (less contact with press plates). The correlation of bioburden to HAI transmission was not studied here so the significance of bioburden alone in the absence of HAI monitoring is uncertain.

Antimicrobial efficacy of triple antibiotic-loaded chitosan nanoparticles activated with photochemical disinfection: A microbiological and confocal microscopic analysis.

Introduction:This in-vitro study comprises Antimicrobial and Confocal Microscopic analysis of the efficacy of Triple Antibiotic and Toluidine Blue (TBO) loaded chitosan nanoparticles (chnp) activated with photodynamic therapy (PDT) against Enterococcus faecalis (Ef).Methodology:105 single-rooted extracted teeth were decoronated, cleaned and shaped, and incubated with Ef. The roots were randomly divided into three groups: Group I-Control, Group II-Triple Antibiotic Paste (TAP), Group III: Triple antibiotic-loaded chitosan nanoparticles (tachnp), and Group IV: Tachnp and TBO loaded chnp activated with PDT. Ten specimens from all the groups were subjected to antimicrobial analysis and five specimens were observed under the confocal microscope after 24 h and 7 days. Group IV was additionally analyzed after 24 h and 7 days of laser activation.Results:Group IV C showed the least colony-forming units followed by Group IVB, Group IIIB, Group IVA, and Group IIIA. Group II showed more colony-forming units. On intergroup comparison of mean colony count in control and experimental groups at 24 h and 7 days using one-way ANOVA F test was highly significant P < 0.001. The confocal microscopic images of IV C showed the increased intensity of fluorescent red indicating dead bacteria.Conclusion:Within the limitations of this study, TAP loaded chitosan nanoparticles activated with PDT showed a significant reduction in colony count.

Antimicrobial Efficacy of Triple Antibiotic Paste and Propolis as an Intracanal Medicament in Young Permanent Teeth: An In Vivo Study.

Aim and objectiveTo evaluate the antimicrobial efficacy of triple antibiotic paste and propolis extracts as an intracanal medicament in young permanent teeth.Materials and methodsA total of 30 single-rooted non-vital young permanent teeth with open apex were selected randomly from the children aged between 7 years and 14 years with no systemic complications. Group I—triple antibiotic paste and group II be propolis allocating 15 teeth in each group. After access opening, the first sample (S1) was collected by inserting paper point into the root canal, the second sample (S2) was collected immediately after irrigation, and the third sample (S3) was collected after post-intracanal medication after 3–4 weeks. Samples were sent for microbiological analysis to assess the bacterial count, and for the obtained data, statistical analysis was done.ResultsThe mean colony count among the triple antibiotic paste group was 1906.75. After access opening, which was reduced to 315.12 after irrigation, and after 3–4 weeks, it was 817.25. There was a significant difference between sample 1, sample 2, and sample 3 (p value = 0.008). The mean colony count among the propolis group was 1427.87 after access opening, which was reduced to 436.00 after irrigation, and after 3–4 weeks, it has reduced to 252.37. There was a significant difference between sample 1, sample 2, and sample 3 (p value = 0.032). Intergroup comparison between the groups showed no statistical difference between the samples.ConclusionPropolis exhibited similar antimicrobial efficacy, which is comparable to triple antibiotic paste. So, propolis can be utilized as an intracanal medicament in young permanent teeth with an open apex.Clinical significancePropolis is a naturally occurring flavonoid-rich resinous product with antibacterial, antifungal, antiviral, immunomodulatory, and antioxidant effects. It is safe without any drug allergies and bacterial sensitivity and is a promising alternative to triple antibiotic paste for disinfecting non-vital young permanent teeth.How to cite this articleLillygrace E, Kethineni B, Puppala R, et al. Antimicrobial Efficacy of Triple Antibiotic Paste and Propolis as an Intracanal Medicament in Young Permanent Teeth: An In Vivo Study. Int J Clin Pediatr Dent 2021;14(2):243–248.

Toxigenic mycoflora, aflatoxin and fumonisin contamination of poultry feeds in Ghana

The study was undertaken to identify the major mycotoxigenic fungi, aflatoxin and fumonisin levels in prepared poultry feeds in Ghana. Three hundred and fifty (350) prepared feed samples were randomly collected from 133 commercial poultry farms, 76 feed processors and eight (8) feed vendors in three major poultry producing regions of Ghana over two seasons. Fungi were isolated using the serial dilution method on potato dextrose agar and identified using standard methods of identification. Total aflatoxin and fumonisin levels were quantified using AgraStrip® Total Aflatoxin and Fumonisin Quantitative test Watex® from RomerLab, USA. Eight (8) different fungi were isolated from the feed samples with isolation frequency as follows: Aspergillus flavus (47%), A. niger (24%), A. fumigatus (17%), A. oryzae (3%), A. tamarii (2%), Penicillium sp. (3%), Colletotrichum sp. (4%) and Rhizopus sp. (0.1%). Feed samples collected during the rainy season recorded higher mean colony counts (3.39 ± 0.29) than that of the dry season (1.10 ± 0.18). Total aflatoxin and fumonisin levels ranged from 0 to 118 ppb with a mean of 57.25 ± 2.55 ppb, and 0.28–15 ppm with a mean of 1.54 ± 0.12 ppm, respectively. The study revealed co-occurrence of aflatoxin and fumonisin in all the feed samples. Significant correlations (r = 0.298, r = 0.694) (p < 0.05) were observed among the aflatoxin and fumonisin levels and the fungi isolated. Seventy-four percent (74%) of all the feed samples exceeded the 15 ppb Ghana Standards Authority threshold, the EU regulatory limit of 20 ppb and the FAO/WHO recommended maximum permissible limit of 30 ppb for poultry feeds. Although fumonisin levels were less than the EU guidance values of 20 ppm for poultry feeds, 20% of the samples were higher than the FAO/WHO maximum tolerable daily intake limit of 2 ppm. Proper handling of prepared feeds and ingredients could prevent or minimize toxigenic fungi contamination and lower the likelihood of mycotoxin development in poultry feeds.