Decontamination Procedures Research Articles

Microorganisms isolated from thermoplastic masks and storage racks in head and neck cancer patients with radiation dermatitis.

Healthcare-associated infections (HAIs) remain a critical public health issue, as they contribute to prolonged treatment duration, increased healthcare costs, and heightened risks of morbidity and mortality. In head and neck cancer patients undergoing radiotherapy, thermoplastic masks (TMs), which come into direct contact with the skin, represent a potential vector for infection. Additionally, the storage racks where these masks are kept may also facilitate microorganism transmission. Our study aimed to isolate and identify microorganisms from infective skin lesions secondary to radiation dermatitis in head and neck cancer patients, as well as from the TMs and storage racks, and to evaluate the antibiotic resistance profiles of the isolated microorganisms. The study included 71 locally advanced head and neck cancer patients who underwent radiotherapy between August 2022 and November 2023. Patients were monitored daily, and their skin evaluations were made according to Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Grade 2 and 3 radiodermatitis was observed in 29 of these 71 patients. Samples were collected using sterile swabs from the skin lesions on the head and neck area, the inner surfaces of the TM, and the storage rack from 29 patients. Samples were inoculated into enrichment and selective media. After the growing microorganisms were identified, antimicrobial susceptibility was evaluated using conventional methods and automated systems according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. At least one type of microorganism was isolated from the skin samples of infected patients, and double growth was detected in two patients. Among the samples, 2 were methicillin-resistant coagulase-negative Staphylococcus (MRCNS), 1 was methicillin-resistant Staphylococcus aureus (MRSA), 1 was Candida albicans (C. albicans), 15 were methicillin-sensitive coagulase-negative Staphylococcus (MSCNS), 1 was methicillin-sensitive Staphylococcus aureus (MSSA), 1 was Bacillus subspecies (Bacillus spp.) and 3 were Corynebacterium diphtheriae (C. diphtheriae). Coagulase-negative Staphylococcus strains were isolated from the skin of 14 of 19 patients with grade 2 radiation dermatitis, whereas CNS strains were isolated from only 2 of 10 patients with grade 3 radiation dermatitis. Among the gram-negative bacteria, 3 Pseudomonas aeruginosa (P. aeruginosa), 2 Enterobacter cloacae (E. cloacae), 1 Klebsiella pneumoniae (K. pneumoniae) and 1 Moraxella catarrhalis (M. catarrhalis) strain were isolated. Sixteen (55.1%) of the TMs used in 29 patients and 20 (68.9%) of the storage racks harbored microorganisms, including HAI agents and flora bacteria. Bacteria colonize TMs and storage racks where they are risk factors for secondary skin infections in radiation dermatitis lesions that develop on the skin of head and neck cancer patients. Decontamination procedures should be meticulously applied to surfaces such as TMs and their storage racks during the course of radiotherapy.

Existing operational standards for field deployments of rapid response mobile laboratories: a scoping review

IntroductionRapid response mobile laboratories (RRML) play an important role in responding to emergencies such as outbreaks and humanitarian crises, working in coordination with national authorities. This scoping review aims to provide evidence to support the development of minimum operational standards for the deployment of RRMLs across the five key workstreams: operational support and logistics, biosafety and biosecurity, laboratory information management system, quality management systems and interoperability and coordination.MethodsWe searched PubMed, MEDLINE, EMBASE and the grey literature focusing on RRML deployment missions. Study characteristics such as year, country, objectives, methods, and findings were extracted and summarized to identify common themes, gaps, and patterns. The results were presented in a narrative format. We ensured methodological rigor by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines throughout the review process.ResultsOut of 163 full-text studies assessed for eligibility, 46 met the inclusion criteria and were analyzed. Six studies addressed the five RRML workstreams. Operational support and logistics are most commonly addressed during pre-deployment phases with a focus on personnel, transport and cold chain management. The application of biosafety and biosecurity protocols is most addressed during the mission execution phase, particularly in the use of personal protective equipment and the implementation of decontamination and disinfection procedures. The laboratory information management system procedures most frequently reported include sample identification and result dissemination protocols. The quality management system workstream overlaps significantly with the other four workstreams, with a strong emphasis on internal and external quality assurance measures. Coordination and interoperability aspects involve maintaining multiple collaborations, ranging from coordinating with local authorities to establishing international partnerships. Common field challenges included interrupted data transfer in areas characterized by poor connectivity and difficulties caused by extreme weather conditions.DiscussionThis review highlights RRML deployment procedures and addresses some critical challenges concerning their deployment. It suggests the provision of a pre-deployment logistics checklist, the use of a pre-determined standardized dataset for inputs to reduce data entry errors and the application of standardized internal and external quality assurance measures.

An Etiology of Sputum Culture Contamination and their Drugs Susceptibility Patterns among TB-suspected Patients at Epicentre Mbarara Research Centre, Uganda

Aims: Contamination in TB cultures is problematic as it allows the growth of non-target bacterial or fungal species in sputum samples, potentially concealing M. tuberculosis. This study aimed to determine the prevalence, characterization, and drug susceptibility patterns of contaminants in sputum cultures from TB-suspected patients. Methods: A laboratory-based cross-sectional study was conducted from October 2023 to June 2024 at the Epicentre Mbarara Research Centre, involving 81 sputum samples from TB-suspected patients. Conventional decontamination procedures were used, and both solid Lowenstein Jensen (LJ) and liquid Mycobacterium Growth Indicator Tube (MGIT) culture methods were applied. Standard culture techniques and physicochemical analyses were employed. Bacteria were incubated at 37°C in O2 and Co2 incubators, with growth observed within 24 to 48 hours and up to three days for yeast contaminants. Sabouraud Dextrose Agar cultures were monitored for two weeks for filamentous fungi. Antibiograms for bacterial isolates were determined using the Kirby-Bauer, while broth microdilution was used for fungal isolates. Results: Of 81 samples, 14(17.28%) were contaminated. The most common bacterial contaminants were Staphylococcus aureus, Bacillus subtilis, Streptococcus viridans, Staphylococcus epidermidis, and Escherichia coli. Fungal contaminants included Aspergillus flavus, Penicillium species, Candida albicans, Cryptococcus neoformans, and non-albican Candida species. High resistance to erythromycin (73%) and tetracycline (50%) was noted among bacterial isolates, with sensitivity to vancomycin (67%), gentamycin (60%), and chloramphenicol (58%). Yeast isolates showed (87.5%) susceptibility to itraconazole and (75%) to amphotericin B but (50%) resistance to 5-flucytosine. Mold isolates exhibited (100%) susceptibility to itraconazole, amphotericin B, and 5-flucytosine but complete resistance to caspofungin. Conclusion: The level of contamination in TB cultures was noted, and Staphylococcus aureus and Candida albicans were observed as the most common contaminants. Bacterial isolates resisted erythromycin and tetracycline, while fungal isolates were generally susceptible to itraconazole and amphotericin B. We recommend Strengthening decontamination and monitoring common resistant contaminants.

Evaluation of emergency nurses’ knowledge of medical response in nuclear and radiological emergencies : a cross-sectional study

BackgroundEvaluating emergency room nurses’ knowledge of radiation protection, health effects, and decontamination procedures is crucial for preparedness in nuclear and radiological emergencies. This study aims to evaluate the level of knowledge among emergency nurses in Saudi Arabia regarding medical responses to nuclear and radiological emergencies.MethodsA multicenter cross-sectional study was conducted via a self-structured questionnaire with 15 true‒false questions divided into three domains, namely, radiation protection measures, radiation health effects, and decontamination procedures, each with five items and a possible score of 1 point per correct answer. The collected data were analyzed via descriptive and inferential statistics. The study followed the STROBE checklist for methodological rigor.ResultsA total of 594 emergency nurses participated in this study, with the majority being young (64.50% aged ≤ 30), female (68.69%), bachelor’s degree-holding (67.68%), single (63.64%), having ≤ 4 years of experience (56.06%), working in public health facilities (88.89%), and lacking training in medical response (85.35%). The mean knowledge scores for participants were highest for radiation exposure effects (3.27 ± 0.91), followed by radiation protective measures (2.32 ± 0.99), and lowest for decontamination procedures (1.46 ± 1.07). Overall knowledge was measured at a mean score of 7.06 ± 1.68, with 97.47% of the nurses categorized as having poor knowledge level. Nurses in private hospitals scored higher (7.77 ± 1.82) than those in public hospitals (6.97 ± 1.65) on overall mean knowledge (P = 0.034). Concerning findings include emergency nurses’ misconceptions about the protection provided by dense materials, the effectiveness of increasing distance from a radiation source, and prioritizing decontamination of victims over life-saving measures. Additionally, they were unaware of the immediate symptoms following radiation exposure and misunderstood that the primary threat in a radioactive bomb event is the explosion rather than the radiation itself.ConclusionThis study revealed poor knowledge among emergency nurses regarding medical responses to radiation emergencies and highlighted the critical need for enhanced and standardized training in radiation emergency preparedness among nurses. The gaps in knowledge identified in this study could significantly impact the effectiveness of healthcare responses in radiation emergency scenarios. Therefore, targeted educational interventions and policy changes are recommended to address these shortcomings.

Prevalence of acute kidney injury and outcome in cats treated as inpatients versus outpatients following lily exposure.

To investigate the prevalence of acute kidney injury (AKI) and outcome in cats treated for lily exposure as inpatients (IPs) or outpatients (OPs). Medical records of cats with lily exposure were retrospectively evaluated; 112 cats were included. Signalment, type of exposure, time from exposure to presentation, decontamination procedures, treatment group (IPs vs OPs), creatinine and International Renal Interest Society AKI grade at specific time points (initial presentation, 0 to 24 hours, 24 to 48 hours, and 48 hours to 2 weeks), whether an AKI developed at any point, whether AKI grade was static or improved when comparing baseline to last documented AKI grade, and outcome (alive or dead/euthanized) were recorded. There were no significant differences in prevalence of AKI between the IP cats (45 of 96 [46.9%]) and OP cats (7 of 16 [43.8%]). Of the AKI cats, 27 IP cats (60%) and 4 OP cats (57.1%) had a static or improved AKI grade. Inpatient cats had a significantly higher survival compared to OP cats (100% vs 86.5%). Cats exposed to lilies in both groups had a higher prevalence of AKI than previously reported; however, many cats with AKIs had a static or improved AKI grade by the last documented AKI grade. Although the survival was lower in OP cats compared to IP cats, overall survival was excellent. Results of our study suggested that IP cats have a superior outcome than OP cats; however, cats treated as OPs may still have favorable outcomes.

Qualitative Comparison of Hydrogen Peroxide Decontamination Systems: Vapor vs. Aerosol

This study aimed to compare the efficiency of two methods for airborne surface decontamination: hydrogen peroxide vapor (HPV) and aerosolized hydrogen peroxide (aHP). Spores of G. stearothermophilus and B. atrophaeus were exposed to a 35% hydrogen peroxide solution under controlled laboratory conditions, including specific concentrations, exposure durations, humidity levels, and temperatures. Following each decontamination procedure, the spores were incubated for 7 days to evaluate bacterial growth and assess the efficacy of each method. The results indicate that the aHP method achieved biocidal rates of 84.76% for G. stearothermophilus and 89.52% for B. atrophaeus, while the HPV method demonstrated respective rates of 90.95% and 90.48%. These findings suggest that both the aHP and HPV methods are highly effective for microbial decontamination, with HPV showing a slight edge in overall efficacy. However, despite its comparable effectiveness, the HPV method has raised concerns regarding technical and economic factors. Observations highlighted issues such as fluctuations in humidity levels causing surface damage, a problem not encountered with the aHP method. Economically, HPV requires specific devices that can cost up to EUR 50,000, whereas aHP equipment costs do not exceed EUR 10,000. These observations emphasize the importance of critically evaluating the pros and cons of each decontamination method, taking into account factors such as biocidal efficacy, technical feasibility, and the associated costs.

Intratumoral microbiota of pancreatic ductal adenocarcinoma impact patient prognosis by influencing tumor microenvironment

BackgroundPancreatic ductal adenocarcinoma (PDAC) is characterized by a highly metastatic potential and a heterogeneous tumor microenvironment. It exhibits limited sensitivity to conventional therapies, necessitating a deeper understanding of its pathogenesis. The role of the intratumoral microbiome in regulating cancer development in PDAC has been the subject of debate. Previous investigations into intra-tumor microbiomes have yielded uncertain results due to sample size limitations and insufficient decontamination procedures. Further research is imperative to elucidate the intricate relationship between intra-tumor microbiomes, the immune landscape of PDAC, and overall prognosis.ResultsOur findings revealed that the intratumor microbiota in PDAC tissue exhibited lower diversity and distinct communities compared to non-tumor tissues. The top microorganisms distinguishing between patients with long or short survival were used to construct the risk signature. We found that Stenotrophomonas is implicated in short survival of PDAC patients, while Neorickettia and Mediterraneibacter are correlated with long survival. This microbiome-based PDAC subtyping, grounded in prognosis-related signatures, exhibited significant correlations with distinct clinical prognoses and immune microenvironments. Microorganisms associated with negative prognoses were linked to pro-tumor immune activation, while those associated with positive prognoses were linked to anti-tumor immune response activation and a more favorable prognosis.ConclusionsOur PDAC subtyping approach, based on a microbiome-derived prognostic risk signature, unveiled compelling associations between the PDAC microbiota and disparities in both clinical prognosis and the tumor microenvironment. These findings suggest that microbiota may serve as a promising biomarker for predicting the prognosis of PDAC.

Long-term inflammatory outcome after placement of a novel two-piece dental implant in a dog model experimental peri-implantitis.

Evaluate the inflammatory outcome of a two-piece novel titanium dental implant (test article) vs. a one- piece titanium dental implant (control article) inducing experimental peri-implantitis in a dog model. A novel, two-piece pre-assembled implant with a 0.2-thickness sleeve in its coronal 4.2mm part was developed (Test article). Ligature-induced experimental periimplantitis model was applied, followed by decontamination and bone grafting in seven dogs. Four groups were assessed according to decontamination and resurfacing protocol: E1 (Experimental 1): test article- sleeve removed, mechanical and chemical decontamination, new rough surface non-threaded sleeve was inserted; E2 (Experimental 2): test article- sleeve removed, mechanical and chemical decontamination, test article remained denuded presenting a turned non-threaded surface; C1 (Control 1): sleeve remained, mechanical and chemical decontamination in test article, original rough surface, non-threaded sleeve; C2 (Control 2): control article cleaning, mechanical and chemical decontamination of original rough surface, threaded implant. Buccolingual and mesiodistal sections were prepared for each site. Resin qualitative and semi-quantitative histopathologic inflammatory parameters were analyzed. Group C1 showed statistically significant highest signs of residual long-term inflammation, followed by groups E1, and C2. Group E2 displayed the lowest local inflammation. Mesio/Distal aspects displayed increased long-term inflammatory infiltrate albeit not statistically significant. Within the limits of the present study, it may be concluded that - (1) The decontamination procedure is more effective in a commercial one-piece vs. a two-piece dental implant. (2) Mechanical and chemical decontamination outcome is insufficient. Resurfacing improves the decontamination outcome. (3) Decontamination of the turned surface is superior to the rough surface. When choosing the most appropriate dental implant for individuals with a high risk for peri-implant disease, a one-piece dental implant with a turned crestal surface is preferable. Once occurring, the control of peri-implant disease inflammation may be more successful. Decontamination is usually not enough. Resurfacing is highly recommended if possible.

Two-step or one-step – are all methods for neonatal incubator decontamination equal?

Healthcare associated pathogens, including Staphylococcus capitis, can contaminate incubator surfaces and are of significant concern in neonatal intensive care units (NICUs). Effective incubator decontamination is essential for infection prevention and control, with submersion decontamination often recommended. This may not always be achievable, with wipe decontamination seen as an alternative. Here we compare the ability of a two-step (submersion in enzymatic detergent followed by wiping with hypochlorite-based wipes) with a one-step (wiping with quaternary ammonium compound-impregnated wipes) decontamination procedure to remove microbial surrogate markers from neonatal incubator surfaces. Three Cauliflower Mosaic Virus derived microbial surrogate markers were inoculated onto the fan, a mattress seam and the external arm port door clips of two Giraffe™ Omnibed™ Carestation™ incubators. Incubators were decontaminated either by the one-step or two-step decontamination process. Swab samples were collected from 28 sites on each incubator and surrounding environment, with marker presence determined by qPCR. Following two-step decontamination, 3/28 (11%) sample sites were positive for any marker, compared to 12/28 (43%) after one-step decontamination. Markers were transferred to several incubator surfaces and recovered from the originally inoculated sites following one-step decontamination, with the marker inoculated on door clips having the greatest transfer. Markers inoculated onto the mattress persisted through both decontamination strategies. Microbial surrogate markers were not completely removed from incubator surfaces by one-step decontamination alone. Two-step decontamination was the most effective method and removed markers from submergible surfaces, but not from the mattress. These findings indicate microorganisms can persist after incubator terminal decontamination, particularly on mattresses and when a two-step decontamination process is not used. This highlights the importance of effective decontamination practices to mitigate microorganism persistence on incubator surfaces.

The Veterinarian’s Role in Biocontainment Research Animal Facilities and Prevention of Spread of Pathogens: A Case of Nigeria and South Africa

Infections acquired in research laboratories and unintentional pathogen escapes from breaches in biocontainment pose risks to humans and the environment, necessitating the need for effective biosafety and biosecurity management frameworks in biocontainment research animal facilities (BRAFs). We examine key biosafety issues associated with BRAFs, including inadequate decontamination procedures for wastewater and experimental samples, handling high biosafety level pathogens in lower-level laboratories, risks of animal bites and sharps injuries, contamination of bedding and enrichment materials, and improper management and transportation of biohazard samples. Additionally, we discuss the role of veterinarians in research animal facilities and the challenges they encounter in maintaining biocontainment standards. We emphasise the importance of routine monitoring of effluent water to detect possible disease outbreaks. We recommend a thorough investigation of disease outbreaks to identify potential sources of pathogen release from BRAFs, which could serve as hotspots for future disease outbreaks. Findings from such investigations will inform the development of policies aimed at safeguarding human populations from future pandemics and preventing BRAFs from becoming sources of infectious disease outbreaks.

Effect of Blood Decontamination Procedures on the Microshear Bond Strength of Resin-modified Glass Ionomer Cement to Resin Composite.

To investigate the effect of decontamination procedures on the microshear bond strength (μSBS) of blood-contaminated resin-modified glass ionomer cement (RMGIC) bonded to resin composite (RC). Eighty RMGIC disc specimens were allocated into 5 groups (n=16). All groups except Group 2 were contaminated with blood. Group 1 had no decontamination procedure, Group 3 was decontaminated by rinsing, Group 4 was decontaminated by 34% phosphoric acid etching, and Group 5 was decontaminated by 5% sodium hypochlorite application. RMGIC specimens were subsequently bonded with RC using a universal adhesive in self-etch mode. μSBS tests were conducted using a universal testing machine at a crosshead speed of 1 mm/min. Failure mode analysis was conducted on RMGIC fracture surfaces under a scanning electron microscope. μSBS results indicated that Group 4 had the highest mean μSBS value of 6.22 ± 2.14 MPa, while Group 1 had the lowest mean μSBS value of 3.53 ±1.67 MPa. Significant differences were observed in the μSBS of Group 2 with no contamination (p=0.023) and Group 4 with decontamination by phosphoric acid-etching (p=0.003) when compared to Group 1 with blood contamination. No statistically significant differences (p>0.05) were observed between all other groups' μSBS. For all groups, the predominant mode of failure was adhesive failure between the RMGIC-RC interface, with a few mixed failures in RMGIC for Groups 2-5. Blood contamination before adhesive application significantly reduced the μSBS between RMGIC and RC. Phosphoric acid etching was the most effective blood decontamination procedure to improve the μSBS.

A comparison of four decontamination procedures in Reusing healing abutments: An in vitro study

ObjectivesThis study aimed to compare the effect of four decontamination methods on the level of residual contaminants in the re-usage of dental healing abutments. Materials and methodsIn this experimental study, 50 used healing abutments were divided into five groups of ten as follows: 1. Control group: healing abutments were submerged in the ultrasonic device then autoclaved at 121 °C for 15 min; 2. Hypochlorite group: Same procedure as the control group, but the healing abutments were additionally immersed in 3 % hypochlorite for 20 min; 3. Chlorhexidine group: Same procedure as the control group, but the healing abutments were additionally treated with 12 % chlorhexidine; 4. Air polishing group: Same procedure as the control group, but the healing abutments were subjected to air polishing; 5. Hydrogen peroxide group: Same procedure as the control group, but the healing abutments were additionally exposed to 3 % hydrogen peroxide. Then, all healing abutments were stained with a protein-specific stain, Phloxine B. Five photographs were taken of each healing abutment, with four capturing the body (shank)and one capturing the top. All images were analysed, to measure the stained (contaminated) areas of each sample. The obtained data were analysed using statistical software (significance set at p < 0.05). ResultsThe one-way ANOVA test indicated that the average percentage of contamination residues on the occlusal surface did not show a significant difference among the five groups: control: 5.5 ± 2.8, sodium hypochlorite: 4.9 ± 2.5, Chlorhexidine: 5.3 ± 2.5, air polisher: 3.1 ± 1.8 and Hydrogen peroxide: 4.8 ± 3.1. (p = 0.26). The average percentage of residual contamination on the body surfaces (shank part) was significantly lower in the air polisher (1.7 ± 1.1) and sodium hypochlorite (2.4 ± 1.1) groups compared to the other three groups (Control: 6.1 ± 2.3, Hydrogen peroxide: 4.6 ± 0.7, Chlorhexidine: 5.4 ± 2.4) (p < 0.05). ConclusionThe results of this study showed that the use of sodium hypochlorite and air polishing, alongside autoclaving and ultrasonic cleaning, effectively reduced residual contamination on the body surfaces of healing abutments.

Evaluation method investigation of public decontamination time in off-site nuclear emergency under the influence of human factors

Decontamination is an important means to reduce the personnel radioactive contamination under sever nuclear accidents. Public decontamination time estimation with the process simulation is helpful for emergency organizations to improve efficiency. To date, most studies focus on improving personal decontamination technology and decontamination strategies, while research on the overall decontamination process and time estimating is limited. Due to the complex population structure, the unknown contaminated proportion and the complicated psychological emotions, it is hard to quantify the decontamination process and calculate the decontamination time with numerous procedures and diverse facility configurations. Combined with public contaminated proportion, crowd structure and waiting psychology, a public decontamination model based on queuing theory and system dynamics method is established for offsite nuclear emergency to simulate the decontamination process and give an estimate of decontamination time. A hypothetical nuclear leakage accident of Changjiang Nuclear Power Plant in Hainan, China is conducted to simulate the established model. The results show the working status of different facilities at different stages and the changes in waiting queues at different times, which can effectively calculate the duration time of each link and the overall public decontamination progress. A plan for adding devices is provided to meet the decontamination time requirements and control the number of waiting queues within the specified threshold efficiently. The method proposed in this paper could help nuclear emergency decision-makers estimate the public decontamination time, optimize site configuration plans, give guidance on public decontamination procedures and prepare for the subsequent nuclear emergency evacuation.

Contact with Wet Cement-A Preventable Cause of Chemical Burn: Case Report and Discussion.

To review the management of a patient with a chemical burn from wet cement. This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and registered nurses with an interest in skin and wound care. After participating in this educational activity, the participant will:1. Recognize the clinical presentation of a patient with a chemical burn from contact with wet cement.2. Describe features related to the pathophysiology of alkali burns from wet cement.3. Select the proper decontamination procedure after exposure to wet cement.4. Identify steps in the treatment of a patient with a chemical burn from contact with wet cement.

Glove decontamination procedures to prevent pathogen and DNA cross-contamination among frogs.

Working with aquatic organisms often requires handling multiple individuals in a single session, potentially resulting in cross-contamination by live pathogens or DNA. Most researchers address this problem by disposing of gloves between animals. However, this generates excessive waste and may be impractical for processing very slippery animals that might be easier to handle with cotton gloves. We tested methods to decontaminate cotton or nitrile gloves after contamination with cultured Batrachochytrium dendrobatidis (Bd) or after handling heavily Bd-infected Xenopus laevis with layered cotton and nitrile gloves. Bleach eliminated detectable Bd DNA from culture-contaminated nitrile gloves, but gloves retained detectable Bd DNA following ethanol disinfection. After handling a Bd-infected frog, Bd DNA contamination was greatly reduced by removal of the outer cotton glove, after which either bleach decontamination or ethanol decontamination followed by drying hands with a paper towel lowered Bd DNA below the detection threshold of our assay. These results provide new options to prevent pathogen or DNA cross-contamination, especially when handling slippery aquatic organisms. However, tradeoffs should be considered when selecting an animal handling procedure, such as the potential for cotton gloves to abrade amphibian skin or disrupt skin mucus. Disposing of gloves between animals should remain the gold standard for maintaining biosecurity in sensitive situations.

The impact of kit, environment, and sampling contamination on the observed microbiome of bovine milk.

In low-microbial biomass samples such as bovine milk, contaminants can outnumber endogenous bacteria. Because of this, milk microbiome research suffers from a critical knowledge gap, namely, does non-mastitis bovine milk contain a native microbiome? In this study, we sampled external and internal mammary epithelia and stripped and cisternal milk and used numerous negative controls, including air and sampling controls and extraction and library preparation blanks, to identify the potential sources of contamination. Two algorithms were used to mathematically remove contaminants and track the potential movement of microbes among samples. Results suggest that the majority (i.e., >75%) of sequence data generated from bovine milk and mammary epithelium samples represents contaminating DNA. Contaminants in milk samples were primarily sourced from DNA extraction kits and the internal and external skin of the teat, while teat canal and apex samples were mainly contaminated during the sampling process. After decontamination, the milk microbiome displayed a more dispersed, less diverse, and compositionally distinct bacterial profile compared with epithelial samples. Similar microbial compositions were observed between cisternal and stripped milk samples, as well as between teat apex and canal samples. Staphylococcus and Acinetobacter were the predominant genera detected in milk sample sequences, and bacterial culture showed growth of Staphylococcus and Corynebacterium spp. in 50% (7/14) of stripped milk samples and growth of Staphylococcus spp. in 7% (1/14) of cisternal milk samples. Our study suggests that microbiome data generated from milk samples obtained from clinically healthy bovine udders may be heavily biased by contaminants that enter the sample during sample collection and processing workflows.IMPORTANCEObtaining a non-contaminated sample of bovine milk is challenging due to the nature of the sampling environment and the route by which milk is typically extracted from the mammary gland. Furthermore, the very low bacterial biomass of bovine milk exacerbates the impacts of contaminant sequences in downstream analyses, which can lead to severe biases. Our finding showed that bovine milk contains very low bacterial biomass and each contamination event (including sampling procedure and DNA extraction process) introduces bacteria and/or DNA fragments that easily outnumber the native bacterial cells. This finding has important implications for our ability to draw robust conclusions from milk microbiome data, especially if the data have not been subjected to rigorous decontamination procedures. Based on these findings, we strongly urge researchers to include numerous negative controls into their sampling and sample processing workflows and to utilize several complementary methods for identifying potential contaminants within the resulting sequence data. These measures will improve the accuracy, reliability, reproducibility, and interpretability of milk microbiome data and research.

Validation and efficacy of various decontamination solutions in eliminating acephate residues from okra

The experiments were carried out to validate an analytical method and to examine the impact of various decontaminating solutions on the removal of acephate residues from okra. Acephate analysis was performed using HPLC-UV, and sample extraction was done using the QuEChERS method. Method validation encompassed assessing specificity, linearity, precision, accuracy, as well as limits of detection (LOD) and quantification (LOQ). The method exhibited excellent linearity with R2 values ≥ 0.99. LOD and LOQ were determined at 0.5 µg mL−1 and 2 µg mL−1, respectively. The results indicated average recoveries ranging from 80.2% to 83.3% with a % RSD below 5%. The decontamination procedures include rinsing with running tap water, soaking in lukewarm water, 2% CH3COOH, 1% NaCl, 5% NaHCO3, 0.01% KMnO4, and in commercially available decontamination products such as nimwash, veggie clean, and arka herbiwash for a duration 10 minutes. Among all the treatments, soaking in nimwash solution showed remarkable effectiveness (96.75% removal), followed by veggie clean (94.97% removal) and arka herbiwash (95.80% removal). Washing okra samples in running tap water was found to be the least effective compared to other treatments.

Immediate dry decontamination using efficient absorbent materials is beneficial following skin exposure to low-volatile toxic chemicals.

In a chemical mass casualty incident requiring skin decontamination, dry removal using absorbent materials may be beneficial to enable immediate decontamination. The efficacy of absorbent materials has therefore been evaluated, alone or procedures including both dry and wet decontamination, following skin exposure to two low volatile toxic chemicals using an in vitro human skin penetration model. Additionally, removal using active carbon wipes was evaluated with or without the Dahlgren Decon solution. All dry decontamination procedures resulted in a significantly decreased skin penetration rate of the industrial chemical 2-butoxyethanol compared to the control without decontamination. Wet decontamination following dry absorption significantly improved the efficacy compared to dry removal alone. Dry decontamination post-exposure to the chemical warfare nerve agent VX showed no decontamination efficacy. However, dry and wet decontamination resulted in a decreased agent skin penetration rate during the last hour of the experiment. At -15°C, significantly reduced VX skin penetration rates were demonstrated for both dry decontamination alone and the dry and wet decontamination procedure. The Dahlgren Decon solution significantly reduced the amount of VX penetrating the skin, but the active carbon wipe alone did not impact the skin penetration rate. In conclusion, absorbent materials are beneficial for the removal of low-volatile chemicals from the skin, but the degree of efficacy varies between chemicals. Despite the variability, immediate dry decontamination using available absorbent materials prior to wet decontamination is recommended as a general procedure for skin decontamination. The procedure should also be prioritized in cold-weather conditions to prevent patient hypothermia.

Efficacy of common decontamination techniques used in eye care facilities in Ghana

PurposeTo evaluate the efficacy of common methods used in the decontamination of non-critical and semi-critical ophthalmic equipment in Ghana. DesignThis study was conducted in two phases. First, a descriptive cross-sectional study was carried out, followed by a microbiological study MethodsQuestionnaires were distributed online to eye care practitioners. The common decontamination procedures identified from the online questionnaires were used in decontaminating the surfaces of the ophthalmic instruments. Swabs were taken from the instruments both before and immediately after decontamination (within the first 30s), as well as at 10-minute intervals up to 40 minutes after decontamination. The swabs were cultured on nutrient agar for 24 hours at 37 °C, and the contamination levels were estimated. ResultsThe most commonly used disinfection technique in the selected eye clinics in Ghana was the use of Methylated spirit (34 %), and the least, Iso-alcohol swabs (1 %). All the decontamination methods were efficacious in the reduction of contamination levels on the surfaces of ophthalmic instruments. Hand sanitiser, Parazone (sodium hypochlorite), Autoclave, and UV showed highly effective decontamination activity compared to Methylated spirit, Hydrogen peroxide, and Isopropyl alcohol. There was a significant reduction in contamination for each of the time points (p < 0.001), except for 40 minutes after decontamination (p = 0.063ns), when compared to the contamination level before decontamination. ConclusionIn Ghana, commonly used decontamination methods are effective in reducing levels of contamination of ophthalmic instruments, with their recontamination rates comparable to the use of autoclaves and UV germicidal irradiation.

Quantity and Size of Titanium Particles Released from Different Mechanical Decontamination Procedures on Titanium Discs: An In Vitro Study.

Complications such as peri-implantitis could ultimately affect the survival of a dental implant. The prevention and treatment of peri-implant diseases require managing bacterial biofilm and controlling environmental risks, including the presence of pro-inflammatory titanium (Ti) particles in the peri-implant niche. Objectives included the evaluation of the size and quantity of Ti particles released from moderately roughened Ti surfaces during common mechanical surface decontamination methods. One hundred and forty moderately roughened Ti discs were divided into seven groups (n = 20 per group); six groups received mechanical decontamination procedures (ultrasonic scaling (US) with a metal tip and poly-ether-ketone (PEEK) under low and medium power settings, air-polishing with erythritol powder, and Ti brush), and the control group underwent air-water spray using a dental triplex. The rinsing solution was collected for Ti mass analysis using inductively coupled plasma mass spectrometry (ICPMS), as well as for Ti particle size and count analysis under scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). US metal tip instrumentation generated 34.00 ± 12.54 μg and 34.44 ± 6.08 μg of Ti under low and medium power settings, respectively. This amount of Ti generation was significantly higher than other instrumentation methods. The mean Ti particle size of the US groups ranged from 0.89 ± 0.27 μm to 1.25 ± 0.24 μm. No statistically significant difference was found in the particle size among US groups and Ti brush group (1.05 ± 0.11 μm), except for US with the PEEK tip, where a significantly smaller mean particle diameter was found at the low power setting (0.89 ± 0.27 μm). Mechanical instrumentation can produce Ti particulates and modify the implant surfaces. US using a metal tip generated the highest amount of Ti with smaller Ti size particles compared to all other commonly used mechanical surface instrumentations. The EDS analysis confirmed Ti in PEEK US tips. It can be suggested that deterioration from the PEEK US tip and Ti brush, as observed under SEM, is an additional source of Ti release during Ti surface decontamination.