Bacterial contamination monitor

Economical, simple, and fast method uses apparatus which detects bacteria by photography. Apparatus contains camera, film assembly, calibrated light bulb, opaque plastic plate with built-in reflecting surface and transparent window section, opaque slide, plate with chemical packages, and cover containing roller attached to handle

Bacterial and Fungal Contamination of Air conditioners filters and Carpets

Background: Objective: To study the level of colonization by bacteria, and fungi/molds in air conditioners and carpets used in homes, offices,university classrooms, prayer room and laboratories. Methods: A total of 25 different settled dust samples from air conditioners, and carpet vacuum cleaners were investigated in this study. One gram of each sample was emulsified into 9.0mL sterile normal saline. 10-fold dilutions were made in normal saline and 100 µL of each suspension was inoculated onto 2 plates of SabouraudDextrose Agarincubated at 25 °C for 48-72hrs, while 50 µLwas inoculated onto MacConkey and Blood agar plates which were incubated at 37 °C for 48hrs. Results: of the settled dust samples examined, 72 % were found to harbor molds, bacteria and yeasts. Of the total bacteria isolated, Bacillus spp. comprised 60.3%, S.epidermidis (20.7%), S. aureus (17.2%), Gram negative bacilli (1.7%). On the other hand, Aspergillusspp. made up 26.9%, of the total mold isolates, followed byPenicillium spp. (20.9%), Yeast (13.4%), Rhizopus spp. (7.5%), Zygomycetes spp. (3%), Aspergillusniger (3%), Lichtheimiacorymbifera (3%), Microsporum spp. (1.5%) and Unidentified mold in 20.8%. The mean bacterial concentration found was 1.33 x 105Cfu/g of dust. Conclusion: The presence of potentially pathogenic bacteria and molds in the dust samples of the air conditioner filters, and home carpets indicated that our environment is full of microorganism that may affect people's health and expose them to different diseases, this mandates regular cleaning and safe removal of dust from A/C filters and carpets

Services provided in support of the planetary quarantine requirements, January - March 1969

Heat shock effects on bacterial spore recovery and Apollo 9, 10, and 11 microbial contamination dat

Quantifying bacterial transfer from patients to staff during burns dressing and bed changes : implications for infection control

Routine nursing activities such as dressing/bed changes increase bacterial dispersal from burns patients, potentially contaminating healthcare workers (HCW) carrying out these tasks. HCW thus become vectors for transmission of nosocomial infection between patients. The suspected relationship between %total body surface area (%TBSA) of burn and levels of bacterial release has never been fully established. Bacterial contamination of HCW was assessed by contact plate samples (n = 20) from initially sterile gowns worn by the HCW during burns patient dressing/bed changes. Analysis of 24 gowns was undertaken and examined for relationships between %TBSA, time taken for activity, and contamination received by the HCW. Relationships between size of burn and levels of HCW contamination, and time taken for the dressing/bed change and levels of HCW contamination were best described by exponential models. Burn size correlated more strongly (R2 = 0.82, p < 0.001) than time taken (R2 = 0.52, p < 0.001), with levels of contamination received by the HCW. Contamination doubled with every 6–9% TBSA increase in burn size. Burn size was used to create a model to predict bacterial contamination received by a HCW carrying out bed/dressing changes. This may help with the creation of burn-specific guidelines on protective clothing worn by HCW caring for burns patients

A study on staphylococcus aureus and bacillus cereus contamination in pastry products in Gorgan

Background and purpose: Pastry products are an important part of food products in Iran. They are highly consumed now and there is high risk of bacterial contamination in these products. The present study investigated bacterial contamination of creamy pastries with Staphylococcus aureus and Bacillus cereus. Materials and methods: A total of 945 pastry cream (jelly, fruit and plain) samples were randomly taken. All samples were tested according to Iran national standards for microbial tests and data was analyzed in SPSS V.18. Results: The highest level of contamination was found to be with Staphylococcus aureus in summer in pastries with fruit cream (19%). No significant difference was observed in contamination of pastry cream (jelly, fruity and plain) in different seasons (P≥0.05). Conclusion: High level of bacterial contamination in pastry cream calls for more personal and workplace hygiene. © 2015, Mazandaran University of Medical Sciences. All rights reserved

Viruses and drinking water

There is no evidence to indicate that there is a risk of acquiring a virus infection through the consumption of properly treated drinking water, provided the integrity of the distribution system is maintained and there is no post-treatment contamination. The consumption of inadequately treated, untreated or post-treatment contaminated water is, however, associated with a risk of hepatitis A, hepatitis E and viral gastroenteritis. The use of the standard bacterial indicators for water monitoring provides an adequate safeguard against viral contamination

E. coli "super-contaminates" narrow ducts fostered by broad run-time distribution

One striking feature of bacterial motion is their ability to swim upstream along corners and crevices, by leveraging hydrodynamic interactions. This motion through anatomic ducts or medical devices might be at the origin of serious infections. However, it remains unclear how bacteria can maintain persistent upstream motion while exhibiting run-and-tumble dynamics. Here we demonstrate that E. coli can travel upstream in microfluidic devices over distances of 15 millimeters in times as short as 15 minutes. Using a stochastic model relating the run times to the time bacteria spend on surfaces, we quantitatively reproduce the evolution of the contamination profiles when considering a broad distribution of run times. Interestingly, the experimental data cannot be reproduced using the usually accepted exponential distribution of run times. Our study demonstrates that the run-and-tumble statistics determine macroscopic bacterial transport properties. This effect, that we name "super-contamination", could explain the fast onset of some life-threatening medical emergencies.Comment: 9 pages, 9 figure

Optimization of 15 parameters influencing the long-term survival of bacteria in aquatic systems

NASA is presently engaged in the design and development of a water reclamation system for the future space station. A major concern in processing water is the control of microbial contamination. As a means of developing an optimal microbial control strategy, studies were undertaken to determine the type and amount of contamination which could be expected in these systems under a variety of changing environmental conditions. A laboratory-based Taguchi optimization experiment was conducted to determine the ideal settings for 15 parameters which influence the survival of six bacterial species in aquatic systems. The experiment demonstrated that the bacterial survival period could be decreased significantly by optimizing environmental conditions

Fluorescence characterization of clinically-important bacteria

Healthcare-associated infections (HCAI/HAI) represent a substantial threat to patient health during hospitalization and incur billions of dollars additional cost for subsequent treatment. One promising method for the detection of bacterial contamination in a clinical setting before an HAI outbreak occurs is to exploit native fluorescence of cellular molecules for a hand-held, rapid-sweep surveillance instrument. Previous studies have shown fluorescence-based detection to be sensitive and effective for food-borne and environmental microorganisms, and even to be able to distinguish between cell types, but this powerful technique has not yet been deployed on the macroscale for the primary surveillance of contamination in healthcare facilities to prevent HAI. Here we report experimental data for the specification and design of such a fluorescence-based detection instrument. We have characterized the complete fluorescence response of eleven clinically-relevant bacteria by generating excitation-emission matrices (EEMs) over broad wavelength ranges. Furthermore, a number of surfaces and items of equipment commonly present on a ward, and potentially responsible for pathogen transfer, have been analyzed for potential issues of background fluorescence masking the signal from contaminant bacteria. These include bedside handrails, nurse call button, blood pressure cuff and ward computer keyboard, as well as disinfectant cleaning products and microfiber cloth. All examined bacterial strains exhibited a distinctive double-peak fluorescence feature associated with tryptophan with no other cellular fluorophore detected. Thus, this fluorescence survey found that an emission peak of 340nm, from an excitation source at 280nm, was the cellular fluorescence signal to target for detection of bacterial contamination. The majority of materials analysed offer a spectral window through which bacterial contamination could indeed be detected. A few instances were found of potential problems of background fluorescence masking that of bacteria, but in the case of the microfiber cleaning cloth, imaging techniques could morphologically distinguish between stray strands and bacterial contamination