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Qualitative Analysis of Indoor and Outdoor Airborne Fungi in Cowshed  [PDF]
R. Pavan,K. Manjunath
Journal of Mycology , 2014, DOI: 10.1155/2014/985921
Abstract: Air pollution is one of the most serious problems to human health. Fungi are the causal agents for different diseases in animals, plants, and human beings. Otomycosis, chronic bronchitis, emphysema, asthma, allergy, and systemic mycosis are among the fungal diseases caused. The present study was conducted to analyze the monthly incidence of airborne fungi, seasonal variation, and influence of meteorological parameters in indoor and outdoor fungi of cowshed at Hesaraghatta village, Bangalore. An aeromycological survey of indoor and outdoor area of cowshed at Hesaraghatta village in Bangalore city was carried out using the Andersen two-stage sampler onto a petri dish containing malt extract agar from January 2011 to December 2011. Altogether, 29 species belonging to 13 genera from indoor and 26 species belonging to 12 genera were recorded from outdoor environment of the cowshed; the dominant fungal species identified were Cladosporium sp., Aspergillus sp., and Alternaria alternata. Seasonal occurrence of fungal spores in both indoor and outdoor of the cowshed revealed that maximum spores were recorded in summer season followed by winter and rainy season. 1. Introduction Airborne particles are present throughout the environment. Despite the fact that atmospheric air does not favour growth of microorganisms due to lack of nutrients, the microorganisms are present in aerosol form, suspended in the air. The basic sources of microbes are soil, water, animals, and humans and they originate in many different forms and affect visibility, climate, human health, and the quality of life [1]. Airborne microbial quantity and quality vary with time of day, year, and location [2]. Fungi are common in indoor and outdoor environment. Nearly 10% of people worldwide have fungal allergy [3]. Numerous studies have shown that exposure to fungi may be associated with acute toxic effects, allergies, and asthma [4]. Researchers believe that more than 80 genera of fungi are associated with symptoms of respiratory tract allergies [5]. Over 100 species of fungi are involved with serious human and animal infections, whereas many other species cause serious plant diseases [6]. Many fungal spores are involved in respiratory allergies and different kinds of infections [7]. Fungal aerosols produced in animal rearing houses may threaten caretakers and external environment. Respiratory infection or damage may occur in caretakers as well as in animal rearing houses with prolonged exposure to the environment at high microorganism levels [8]. Microbial aerosols of high levels are also
Airborne Microorganisms in Commercial Shell Egg Processing Facilities  [PDF]
J.K. Northcutt,D.R. Jones,K.D. Ingram,A. Hinton
International Journal of Poultry Science , 2004,
Abstract: Total aerobic bacteria, molds/yeasts, coliforms and pseudomonads in the air in three shell egg processing operations (in-line, off-line and mixed operations) were determined using MicroBio MB2 Air Samplers. Sites were sampled from each facility on three different days (replication) during the same week. Four air samples (1000 L each) were drawn from each sampling site on a given day. Sampling sites, included areas in or near the following on-site locations: hen house (in-line and mixed operations), farm transition room (in-line and mixed operations), egg washers, egg dryer, packer heads, post-processing cooler, nest-run cooler (off-line and mixed operations), loading dock and dry storage. Type of operation (in-line, off-line or mixed), sampling site and the interaction between operation and site had a significant effect on the number of total aerobic bacteria, molds/yeasts, coliforms and pseudomonads recovered (P < 0.05). Highest counts for total aerobic bacteria (5.9 log10 cfu/ml air), molds/yeasts (4.0 log10 cfu/ml air) and coliforms (2.5 log10 cfu/ml air) were found in the hen house. Highest counts for pseudomonads were found in the hen house (3.2 log10 cfu/ml air) and behind the egg washer (3.5 log10 cfu/ml air). Lowest counts for total aerobic bacteria (2.5 log10 cfu/ml air) and molds/yeast (2.7 log10 cfu/ml air) were found in the post-processing cooler. Few samples in the post-processing coolers, nest-run coolers, loading docks and dry storage areas tested positive for coliforms (0/36, 2/24, 1/36 and 0/36, respectively) and pseudomonads (1/36, 2/24, 5/36 and 6/36, respectively). Data gathered during this study has been useful in identifying the sources and levels of airborne contaminates in commercial shell egg processing facilities.
Airborne Fungi in Indoor and Outdoor of Asthmatic Patients’ Home,Living in the City of Sari
Mohammad Taghi Hedayati,Saba Mayahi,Reza Aghili,Kayvan Goharimoghadam
Iranian Journal Of Allergy, Asthma and Immunology , 2005,
Abstract: The aim of this study was identification of fungi in indoor and outdoor of asthmatic patients′ home environment. Opened plates (containing of Malt extract agar media) were used for isolation of fungi in the air of indoor (n=360) and outdoor (n=180) of 90 asthmatic patients home living in the city of Sari at the level of breathing height. Plates were incubated in room temperature for 7-14 days. Then grown fungi were identified by standard mycological techniques. A total of 1876 colonies with 31 and 1692 colonies with 27 genera of fungi were identified from indoor and outdoor of asthmatic patients’ home respectively. The most common fungi isolated were Cladosporium, Aspergillus and Penicillium. Stachibotyris, Oedocephalum, and Stemphillium showed the least frequencies among the isolated fungi. Cladosporium, Aspergillus, Penicillium, and Alternaria as the most common allergenic moulds had the most frequencies in indoor air of the houses of asthmatic patients.
The Efficient Method for Simultaneous Monitoring of the Culturable as Well as Nonculturable Airborne Microorganisms  [PDF]
Barbara Hubad, Ale? Lapanje
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0082186
Abstract: Cultivation-based microbiological methods are a gold standard for monitoring of airborne micro-organisms to determine the occupational exposure levels or transmission paths of a particular infectious agent. Some highly contagious microorganisms are not easily culturable but it is becoming evident that cultivation and molecular methods are complementary and in these cases highly relevant. We report a simple and efficient method for sampling and analyzing airborne bacteria with an impactor-type high-flow-rate portable air sampler, currently used for monitoring culturable bacteria or fungi. A method is reported for extraction of nucleic acids from impacted cells without prior cultivation and using agarose as a sampling matrix. The DNA extraction efficiency was determined in spiked samples and, samples taken from a wastewater treatment plant and an alpine area. The abundance, diversity and quantity of total bacteria were analysed by a quantitative polymerase chain reaction, and by construction and analysis of clone libraries. The method does not interfere with downstream PCR analysis and can cover the gap between traditional culture and molecular techniques of bioaerosol monitoring.
A Metagenomic Framework for the Study of Airborne Microbial Communities  [PDF]
Shibu Yooseph, Cynthia Andrews-Pfannkoch, Aaron Tenney, Jeff McQuaid, Shannon Williamson, Mathangi Thiagarajan, Daniel Brami, Lisa Zeigler-Allen, Jeff Hoffman, Johannes B. Goll, Douglas Fadrosh, John Glass, Mark D. Adams, Robert Friedman, J. Craig Venter
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0081862
Abstract: Understanding the microbial content of the air has important scientific, health, and economic implications. While studies have primarily characterized the taxonomic content of air samples by sequencing the 16S or 18S ribosomal RNA gene, direct analysis of the genomic content of airborne microorganisms has not been possible due to the extremely low density of biological material in airborne environments. We developed sampling and amplification methods to enable adequate DNA recovery to allow metagenomic profiling of air samples collected from indoor and outdoor environments. Air samples were collected from a large urban building, a medical center, a house, and a pier. Analyses of metagenomic data generated from these samples reveal airborne communities with a high degree of diversity and different genera abundance profiles. The identities of many of the taxonomic groups and protein families also allows for the identification of the likely sources of the sampled airborne bacteria.
A Model for the Early Identification of Sources of Airborne Pathogens in an Outdoor Environment  [PDF]
Jeroen P. G. van Leuken, Arie H. Havelaar, Wim van der Hoek, Georgia A. F. Ladbury, Volker H. Hackert, Arno N. Swart
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080412
Abstract: Background Source identification in areas with outbreaks of airborne pathogens is often time-consuming and expensive. We developed a model to identify the most likely location of sources of airborne pathogens. Methods As a case study, we retrospectively analyzed three Q fever outbreaks in the Netherlands in 2009, each with suspected exposure from a single large dairy goat farm. Model input consisted only of case residential addresses, day of first clinical symptoms, and human population density data. We defined a spatial grid and fitted an exponentially declining function to the incidence-distance data of each grid point. For any grid point with a fit significant at the 95% confidence level, we calculated a measure of risk. For validation, we used results from abortion notifications, voluntary (2008) and mandatory (2009) bulk tank milk sampling at large (i.e. >50 goats and/or sheep) dairy farms, and non-systematic vaginal swab sampling at large and small dairy and non-dairy goat/sheep farms. In addition, we performed a two-source simulation study. Results Hotspots – areas most likely to contain the actual source – were identified at early outbreak stages, based on the earliest 2–10% of the case notifications. Distances between the hotspots and suspected goat farms varied from 300–1500 m. In regional likelihood rankings including all large dairy farms, the suspected goat farms consistently ranked first. The two-source simulation study showed that detection of sources is most clear if the distance between the sources is either relatively small or relatively large. Conclusions Our model identifies the most likely location of sources in an airborne pathogen outbreak area, even at early stages. It can help to reduce the number of potential sources to be investigated by microbial testing and to allow rapid implementation of interventions to limit the number of human infections and to reduce the risk of source-to-source transmission.
Removal of airborne microorganisms emitted from a wastewater treatment oxidation ditch by adsorption on activated carbon

Lin Li,Min Gao,Junxin Liu,Xuesong Guo,

环境科学学报(英文版) , 2011,
Abstract: Bioaerosol emissions from wastewater and wastewater treatment processes are a significant subgroup of atmospheric aerosols. Most previous work has focused on the evaluation of their biological risks. In this study, however, the adsorption method was applied to reduce airborne microorganisms generated from a pilot scale wastewater treatment facility with oxidation ditch. Results showed adsorption on granule activated carbon (GAC) was an efficient method for the purification of airborne microorganisms. The GAC itself had a maximum adsorption capacity of 2217 CFU/g for airborne bacteria and 225 CFU/g for fungi with a flow rate of 1.50 m3/hr. Over 85% of airborne bacteria and fungi emitted from the oxidation ditch were adsorbed within 80 hr of continuous operation mode. Most of them had a particle size of 0.65-4.7 μm. Those airborne microorganisms with small particle size were apt to be adsorbed. The SEM/EDAX,BET and Boehm's titration methods were applied to analyse the physicochemical characteristics of the GAC. Relationships between GAC surface characteristics and its adsorption performance demonstrated that porous structure, large smrface area, and hydrophobicity rendered GAC an effective absorber of airborne microorganisms. Two regenerate methods, ultraviolet irradiation and high pressure vapor, were compared for the regeneration of used activated carbon. High pressure vapor was an effective technique as it totally destroyed the microorganisms adhered to the activated carbon. Microscopic observation was also carried out to investigate original and used adsorbents.
Diversity and Distribution Patterns of Airborne Microfungi in Indoor and Outdoor Hospital Environments in Khorramabad, Southwest Iran  [cached]
Masoomeh Shams-Ghahfarokhi,Asghar Sepahvand,Abdolamir Allameh,Mehdi Razzaghi-Abyaneh
Jundishapur Journal of Microbiology , 2013,
Abstract: Background: Nosocomial fungal infections could arise from independent exposure to airborne spores of filamentous fungi existing in the hospital environment..Objectives: The present study aimed to determine the mycoflora of indoor and outdoor environments of five major hospitals in Khorramabad, Iran. .Materials and Methods: Sampling of air was done from indoor and outdoor environments of wards, surroundings and green space of hospitals by settle plate method. To obtain the sample from surfaces, pre-moistened swabs with cotton-tipped sticks were applied on different surfaces (floor, the walls, windows, beds, trolleys, laryngoscope and angiography devices). Culture plates of air and surfaces on Potato Dextrose Agar (PDA) and Malt Extract Agar (MEA) were incubated in the dark at 28 oC and examined daily for fungal colonies for two to three weeks. Fungal isolates were identified by a combination of their macroscopic and microscopic criteria after purification on isolation culture media..Results: A total of 707 fungal colonies including, Penicillium (29.14%), Cladosporium (24.04%), Aspergillus (20.65%), Fusarium (9.05%), Alternaria (3.96%), Rhodotorula (1.69%), Cryptococcus neoformans (0.7%) and other fungi (10.77%) were isolated. All the examined high-risk parts of the hospitals were found to be contaminated by various fungi. .Conclusions: Aspergillus was the most prominent genus in Intensive Care Unit (ICU) and surgery, Cladosporium in Critical Care Unit (CCU), emergency and thalassemia, and Penicillium in orthopedic, emergency and neonatal sections. Among pathogenic yeasts, C. neoformans was isolated from ICU, surgery and orthopedic sections. The dimorphic fungal pathogen, Sporothrix schenckii, was reported from CCU. The isolated fungi specially the genera Aspergillus and Penicillium are potential threats for immunocompromised patients in the hospitals.
Resolving the abundance and air-sea fluxes of airborne microorganisms in the North Atlantic Ocean  [PDF]
Eva Mayol,María A. Jiménez,Gerhard J. Herndl,Carlos M. Duarte,Jesús M. Arrieta
Frontiers in Microbiology , 2014, DOI: 10.3389/fmicb.2014.00557
Abstract: Airborne transport of microbes may play a central role in microbial dispersal, the maintenance of diversity in aquatic systems and in meteorological processes such as cloud formation. Yet, there is almost no information about the abundance and fate of microbes over the oceans, which cover >70% of the Earth's surface and are the likely source and final destination of a large fraction of airborne microbes. We measured the abundance of microbes in the lower atmosphere over a transect covering 17° of latitude in the North Atlantic Ocean and derived estimates of air-sea exchange of microorganisms from meteorological data. The estimated load of microorganisms in the atmospheric boundary layer ranged between 6 × 104 and 1.6 × 107 microbes per m2 of ocean, indicating a very dynamic air-sea exchange with millions of microbes leaving and entering the ocean per m2 every day. Our results show that about 10% of the microbes detected in the boundary layer were still airborne 4 days later and that they could travel up to 11,000 km before they entered the ocean again. The size of the microbial pool hovering over the North Atlantic indicates that it could play a central role in the maintenance of microbial diversity in the surface ocean and contribute significantly to atmospheric processes.
Airborne Microorganisms During the Commercial Production and Processing of Japanese Quail  [PDF]
J.K. Northcutt,D.R. Jones,M.T. Musgrove
International Journal of Poultry Science , 2004,
Abstract: Total aerobic bacteria, molds/yeasts, E. coli and Enterobacteriaceae in the air during the commercial production and processing of Japanese quail were enumerated at twelve different sites. Production-related sampling sites included the breeder and grow-out houses along with the hatchery setter, hatcher, egg room and chick room. Processing-related sampling sites included the hanging/stunning area, scalding/defeathering room, evisceration line, chiller exit, further processing area and shipping room. Sampling site had a significant effect on the log10 counts for total aerobic bacteria, molds/yeasts, E. coli and Enterobacteriaceae and (P < 0.0001). Moreover, significant correlation was found between airborne bacteria counts and both environmental temperature and humidity (P < 0.05). During production, highest counts for total aerobic bacteria (8.1 log10 cfu/ml air), molds/yeasts (3.6 log10 cfu/ml air), E. coli (1.9 log10 cfu/ml air) and Enterobacteriaceae (2.3 log10 cfu/ml air) occurred in the grow-out house. Lowest production-related counts for total aerobic bacteria (3.5 log10 cfu/ml air), molds/yeasts (2.5 log10 cfu/ml air) and Enterobacteriaceae (2.0 log10 cfu/ml air) occurred in the chick room at the hatchery. At the processing facility, highest counts for total aerobic bacteria (6.8 log10 cfu/ml air), E. coli (1.4 log10 cfu/ml air) and Enterobacteriaceae (1.5 log10 cfu/ml air) occurred in the areas where quail are hung/stunned and scalded/defeathered. E. coli was not found at any of the sampling sites in the hatchery (setter, hatcher, egg room, chick room) or at the chiller exit, further processing area or shipping room at the processing facility. Data gathered during this study may be useful in identifying the sources and levels of airborne contaminates in commercial production and processing of quail so that effective intervention practices may be established or strengthened.
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