Number Of Airborne Bacteria Research Articles

A Correlation between the Number of Airborne Bacteria and Fungi using the Settle Plate Method with Temperature and Relative Humidity at the Clinical Microbiology Laboratory of Dr. Soetomo Regional General Hospital Surabaya, Indonesia

Air is an important part of human life. However, air can be contaminated with microorganisms such as airborne bacteria and fungi. Temperature and relative humidity in a room can have an impact on the quantity of airborne bacteria and fungi. This study aims to figure out the correlation between the number of airborne bacteria and fungi with temperature and relative humidity. In 15 rooms of Microbiology laboratory, NA and SDA Petri plates were placed, after incubation, the number of colonies in each plate was counted. Pearson test was conducted with SPSS to determine the correlation between temperature and relative humidity to the number of airborne bacteria and fungi. The highest number of airborne bacteria was in the reading room (352 CFU/m3), while the lowest number was in the laundry room (13 CFU/m3) and the highest number of airborne fungi was in the Mycology room (156 CFU/m3), while there were no airborne fungi found in the urine and laundry rooms. Based on the results of the Pearson test, it was found that the value of p = 0.668 (p> 0.5) showed that there was no correlation between temperature and the number of airborne bacteria and fungi. Based on the results of the Pearson test, the value of p = 0.745 (p> 0.5) showed that there was no correlation between relative humidity and the number of airborne bacteria and fungi. There is no correlation between temperature and relative humidity with the number of airborne bacteria and fungi.

Effect of radiant catalytic ionization on environmental conditions in rodent rooms and the haematological status of mice

High stocking densities, closed animal houses, and elevated concentrations of bacteria, fungi, and the products of their activity, including ammonia and hydrogen sulphide, have adverse health effects. Active techniques used to reduce unfavourable environmental conditions, such as ventilation, sprinkling, bedding sorbents, and nutritional treatments, are not always sufficient to improve the animals’ living environment. The current paper aims to evaluate the effect of radiant catalytic ionization (RCI) on airborne microorganisms, cage microbiological status, gaseous ammonia concentrations, and the haematological status of mice in animal houses. After one week of operation of an RCI system, the number of airborne bacteria and fungi in the experimental room decreased in comparison to the first day of the experiment (p < 0.05 and p < 0.05 respectively), as did the concentrations of ammonia (p < 0.01) and dust. At the same time, the basic health parameters of the mice, determined in the blood, were very similar between the control and experimental room. RCI seems to be an ideal solution to ensure high hygiene standards in animal rooms and houses with limited use of disinfectants or antibiotic treatment of sick animals. An additional, environmental benefit is the limited amount of nitrogen released.

Bacterial community in commercial airliner cabins in China

ABSTRACTConsidering the amount of time that crew members and passengers spend on airliners and the potential health impact of pathogenic bacteria, it is important to understand the population of bacteria inside airliners and the factors affecting the bacterial concentration. This study recorded the species of airborne and cabin surface culturable bacteria inside various airliner. Seven flights ranging from 3 to 5 hours in duration on different types of airliner were chosen. Multiple species of bacteria in the air of the airliners, such as Brachybacterium paraconglomeratum, were identified by means of the 16S ribosomal RNA gene sequencing method, and most of the bacteria were Gram-positive. This study found that the bacterial concentration in the airliners decreases as the relative humidity increases. The decrease in the number of airborne bacteria may be the reason for the reduced occurrence of unwanted symptoms exhibited by passengers.

A study of the energy consumption and airborne microbe concentration in the Sapporo underground walkway, in a cold region of Japan

The present study sought to evaluate the energy consumption, indoor air quality and concentration of airborne bacteria and fungi in the Sapporo underground walkway, which is in a cold region of Japan. The energy consumption, temperature, relative humidity, and carbon dioxide concentrations of the underground walkway were investigated for 4 years from its opening in 2011 (until 2014). The temperature, relative humidity, and carbon dioxide concentrations were automatically detected using sensors and data from Sapporo city hall. To evaluate the microbial contamination in the ventilation system and indoors, the concentrations of airborne bacteria and fungi were measured on 2 days (a weekday and a weekend day) during opening hours in both summer and winter. The concentration of airborne microbes in the supply air, indoor air, and outside air was compared. Species of airborne bacteria were identified using 16S rDNA sequence analysis. The energy use intensities were decreased in 2013, when the walkway temperature was changed during both winter and summer. The carbon dioxide concentration in the walkway was maintained below 1000 ppm. The number of airborne bacteria and fungi in the supply air from the ceiling diffuser was lower than those in the outdoor and indoor air. These results indicate that both energy consumption and indoor air quality were maintained in the walkway throughout the 4-year period. This study could be helpful for developing the related standards for indoor air quality and for developing control strategies to properly operate air conditioning and ventilation systems in underground spaces.

Paper Towels Best for Drying Hands

According to this study: * Jet-air and warm-air hand dryers increased the number of airborne bacteria in the bathroom environment and may not be suitable for use in health care settings. * Visualization tests also showed that droplet dispersal was greatest with the jet-air dryer.

Differences in the correlation between microbiological air sampling and particle counting in operating theatres and hospital cleanrooms

The process of environmental monitoring in cleanrooms of clinical pharmacy and operating theatres is difficult, the measurement of bio burden is time consuming and the result is available several days after the operation. This study examines the correlation between the number of airborne bacteria and particles in operating theatres and cytostatic compounding cleanrooms in order to evaluate if applying solely particle monitoring is sufficient for hygienic-microbiological risk assessment.

Capability of air filters to retain airborne bacteria and molds in heating, ventilating and air-conditioning (HVAC) systems

The capability of air filters (filterclass: F6, F7) to retain airborne outdoor microorganisms was examined in field experiments in two heating, ventilating and air conditioning (HVAC) systems. At the beginning of the 15-month investigation period, the first filter stages of both HVAC systems were equipped with new unused air filters. The number of airborne bacteria and molds before and behind the filters were determined simultaneously in 14 days-intervals using 6-stage Andersen cascade impactors. Under relatively dry (< 80 % R. H.) and warm (> 12 °C) outdoor air conditions air filters led to a marked reduction of airborne microorganism concentrations (bacteria by approximately 70 % and molds by > 80 %). However, during long periods of high relative humidity (> 80 % R. H.) a proliferation of bacteria on air filters with subsequent release into the filtered air occured. These microorganisms were mainly smaller than 1.1 μm therefore being part of the respirable fraction. The results showed furthermore that one possibility to avoid microbial proliferation is to limit the relative humidity in the area of the air filters to 80 % R. H. (mean of 3 days), e. g. by using preheaters in front of air filters in HVAC-systems.

An examination of the air pollution in a dental hospital, with special reference to air-borne bacteria.

The environmental problems in dental clinics claim our attention because of the special nature of dental treatment such as cutting and grinding of the teeth and prosthetic material. In recent years, the air turbine engine developed as a super high speed apparatus for the cutting of teeth has come to be widely used in dental treatment. But because the cutting of teeth has become highly effective, dental cuttings, saliva and bacteria from the mouth of patients cause pollution of the air inside dental clinics.The present study was made of the air-borne bacteria in various clinics at dental hospital N. Pure cultures were made of the bacteria and their bacteriological characteristics were investigated. The following conclusions were obtained.1. Bacterial counts in the clinics were 0.41-2.13/l in April, 0.41-1.41/l in July and 0.30-2.27/l in December. The bacterial count in clinic A for five days was 0.26-1.12/l. The number of air-borne bacteria during dental treatment was to 3.1 to 7.6 times more than during the pre-treatment stage.2. The correlation between the number of patients and bacterial counts in the various clinics was 0.406-0.777. The correlation for five days in clinic A was 0.971. Thus a high correlation was observed between the density of patients and bacterial counts.3. Bacteriological characteristics.1) The air-borne becteria at dental hospital N consisted of 12.4% Myces, 34% bacilli, and 53.6% cocci.2) From the pure cultures of air-borne bacteria, we found that gram-positive cocci were 117 (51.5%), gram-negative cocci were 22 (9.7%), gram-positive bacilli were 71 (31.3%), and gram-negative bacilli were 17 (7.5%).3) Those which proved to be positive in hemolytic reaction either to human or horse blood were 70 (30.8%). Of them, a hemolytic types were 12 and 9 hemolytic types were 55, and 3 proved to be a hemolytic to human blood and β hemolytic to horse blood.4) 5 Gram-positive bacilli were proved to from spores, accounting for 7.0%.5) Among the air-borne bacteria in the clinics, the existence of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Micrococcus, Bacillus subtilis and Serratiawas confirmed.

Hygienic and clinical study of elective and acute hip operations

The effect of hygienic measures in two groups of hip operations was compared. Forty patients had total hip replacement operations (THR) representing elective surgery, and 38 patients had open osteosynthesis of pertrochanteric fractures (PFO) representing acute surgery. THR was performed on non-infected cases after careful skin disinfection whereas PFO was often performed after less effective patient preparation. No patient had antibiotic prophylaxis. The surgical team was dressed in gowns of conventional type. The operating theatre had a so-called zonal ventilation system. The number of airborne bacteria in the operating theatre during operation varied from 6 to 160 cfu/m 3. The mean values were significantly higher during THR than during PFO and the operation time was longer. The operation wound area contained significantly higher levels of airborne bacteria than other parts of the room. Cultures from adhesive drapes showed growth in 33 out of 40 THR and in 24 out of 38 PFO. In the latter group clostridia were found on the drapes more often than in the THR group. Swabs from the wounds taken at the end of the operation showed growth in five THR and in six PFO. The rate of superficial infection was 13 per cent in the THR group and 15·8 per cent in the PFO group. The deep infection rate was 5·4 and 0 per cent, respectively. Most of the infections seemed to be endogenous.

全熱交換器を設置した動物実験施設の空中細菌とアンモニアガス濃度について

The number of air-borne bacteria in air ducts and barrierred laboratory animal rooms with the so-called econovent rotary heat exchanger, were checked monthly during a year by the pin-hole sumpler method for air ducts and Koch method for animal rooms. Also, concentration of ammonia was checked with the same samples by gas impinger. No significantly difference in number of air-borne bacteria was seen between before and after passing the econovent. Those passing through HEPA filter was not detected. There were more air-borne bacteria in animal rooms, outside locker room and shower room than in the corridor, utensil storage, inside locker room and pass box. No ammonia were detected in the outdoor, but exhaust air duct after passing the econovent contained very small amount of ammonia. On the other hand, high concentration of ammonia were preserved in the supplying air duct, exhaust air duct and mice and rats rooms, about 86% of ammonia in exhaust air duct returned back into the supplying air duct. No influences on reproduction in mice and rats were recognized.

Variations of air-borne bacteria in a department of oral surgery.

The variation in the number of airborne bacteria before and after the reconstruction of an oral surgery department was determined in the policlinic and the operating theatre by means of sedimentation plates with bloodagar. The sedimentation plates were kept in analogous locations in both parts of the study and exposed for determined periods during the day. Along with the reconstruction, the hygienic standard was improved by introduction of several changes, such as obligatory use of oral/nasal mask, separated treatment units in the policlinic, decreased movement during surgical procedures, a better isolation of the operating theatre and overpressure ventilation with filtrated air. The results showed a generally significant variation (p<0.01) in the bacterial level correlated with the rate of activity in both parts of the study. Further results showed a very clear decrease in the number of bacteria for both localities. The percentage reduction was found to be 65 per cent in the operating theatre and 50 per ...

実験動物施設における空中細菌について

Some investigations were carried out on airborne bacteria in different parts of laboratories. The results are summarized as follows:1) The numbers of air-borne bacteria were much different among animal rooms under different conditions. (Fig. 2) .2) Bacterial number in the experimental room attained its maximum at daytime and its minimum at night (Fig. 5) . The mean number of air-borne bacteria in animal room however, was larger at night than at daytimes (Fig. 4) . The daily changes of bacterial number in the vestibule were similar to those in the experimental room (Fig.3) .3) The numbers of bacteria in animal rooms before and after introduction of animals was considerably different. (Fig.6 & 7) .4) The numbers of air-borne bacteria in the animal rooms differs with the species of animals. The highest contamination was observed in the rabbit room.5) The difference in number of bacteria between the levels of 170 cm and 20 cm distant from the floor was obserbed (Fig. 6 & 7) .6) Over 90 per cent of the contaminated bacteria were of underf fined micrococci, and the rests were of diphtheroids, coliforms and fungi (Table. 2) .

USE OF ULTRAVIOLET RADIATION IN REDUCTION OF RESPIRATORY CROSS INFECTIONS

Following the installation in this hospital of a new operating room equipped with a battery of eight Westinghouse Sterilamps and an air changing system, counts were made of the bacteria in the air of this room. Either of these agents reduced the number of air borne bacteria. and the combination of the two was very effective.1This suggested the possibility of using similar means to reduce the number of cross infections in the infant ward. In order to test the efficacy of various barriers to the spread of air borne bacteria, an experimental room was set up in the laboratory.2It consisted of a series of open door cubicles the entrances of which were 4 feet wide and 6 feet 2 inches high. Around the cubicle entrances, General Electric Ultraviolet Germicidal lamps (15 watt, T8) were mounted with baffles in front and behind them so that a narrow