Occurrence of fungal spores in the respiratory tract and homes of patients with positive skin test to fungi

The occurrence of fungal spores in the upper respiratory tract and in the homes of 86 patients with allergic manifestations and positive skin tests for fungi has been investigated.Alternaria tenuis andCladosporium herbarum have been more frequently found to give positive reactions, followed byAspergillus mix,Candida albicans andPenicillium notatum. Cladosporium andAlternaria represented also the most common moulds isolated from nasal specimens. The prevalent fungi isolated from patients' environments wereCladosporium, Penicillium andAlternaria, occurring respectively in 93%, 78% and 72% of the homes sampled. An examination of individual cases have revealed a surprisingly close correlation, in 47 out of 86 patients, between positive skin test response and presence in high amount of the same fungi in patient's respiratory tract and home. In the majority of cases the fungi involved wereAlternaria and/orCladosporium.     

Occurrence of fungal spores in the respiratory tract and homes of patients with positive skin test to fungi

The occurrence of fungal spores in the upper respiratory tract and in the homes of 86 patients with allergic manifestations and positive skin tests for fungi has been investigated.Alternaria tenuis andCladosporium herbarum have been more frequently found to give positive reactions, followed byAspergillus mix,Candida albicans andPenicillium notatum. Cladosporium andAlternaria represented also the most common moulds isolated from nasal specimens. The prevalent fungi isolated from patients' environments wereCladosporium, Penicillium andAlternaria, occurring respectively in 93%, 78% and 72% of the homes sampled. An examination of individual cases have revealed a surprisingly close correlation, in 47 out of 86 patients, between positive skin test response and presence in high amount of the same fungi in patient's respiratory tract and home. In the majority of cases the fungi involved wereAlternaria and/orCladosporium.     

Mould biodiversity in homes I. Air and surface analysis of 130 dwellings

Summary Air and surface sampling to quantify and identify fungi were conducted over a 10-year period in 130 Belgian homes, including flats and houses. Homes were selected based on the medical files of allergic, mostly asthmatic patients to assess possible mould responsibility in the aetiology of the disease. Air sampling was done with Reuter centrifugal air sampler using different sampling times and incubation temperatures to detect mesophilic and thermotolerant or thermophilic fungi. More than 50 genera were detected, withCladosporium, Penicillium andAspergillus being the most common. The main species detected wereAspergillus versicolor, several species ofPenicillium, Cladosporium sphaerospermum andCladosporium herbarum. Surface sampling was conducted concomitant with air sampling. Surfaces with and without visible mould growth were tested equally by Rodac contact plates or swabs. AlthoughCladosporium herbarum was shown to be a common species in indoor environments by air sampling, it was not detected by surface sampling from visible mould growth. This finding suggests that its presence in dwellings is from an outdoor origin and not indicative of indoor proliferation.Aspergillus versicolor, Cladosporium sphaerospermun, andPenicillium chrysogenum were the most common species isolated from surfaces showing visible mould growth.     

Prevalence of culturable and non-culturable airborne fungi in a grain store in Delhi

Fungal spores are important aeroallergens and proper knowledge of their qualitative and quantitative prevalence in indoor and outdoor environments is of paramount importance in the study of allergic disorders. The present investigation was aimed at the study of seasonal and annual prevalence of fungi inside a large grain storage facility. Sampling was carried out from September 1989 to August 1991. Although fungal spores occurred throughout the year there was seasonal variation.Aspergillus flavus. Cladosporium spp.Epicoccum nigrum and basidiospores had a definite seasonal pattern.Aspergillus flavus andUstilago (smuts) were the most predominant fungi in the facility. Their concentration was significantly higher (P<0.05) than in outside air. The need to reduce fungal concentration in grain storage is emphasised.     

Airborne fungi in an Italian rice mill

Summary Studies employing volumetric spore trap (VSP) and gravity settling culture plates (GSC) were conducted in order to analyse the air spora of a rice mill at Pavia, Italy, from October-December 1988. Results revealed a variety of fungal spores belonging to different genera and including recognized rice pathogenic fungi. The most frequent genera by GSC method includedAcremonium, Alternaria, Aspergillus, Aureobasidium, Cladosporium, Epicoccum, Fusarium, Helminthosporium, Mucor, Nigrospora, Penicillium, Rhizopus, Trichoderma, Trichothecium, and some unidentified fungi. Environmental assessment of fungal spores by VSP revealed that the most prevalent fungi were:Alternaria, Cladosporium, Epicoccum, Helminthosporium, Nigrospora, Pyricularia, Tilletia and hyaline, dark and coloured types of ascospores and basidiospores. Airborne fungal spore concentrations were particularly high (5,000–6,000 spores/m³) in the rooms of the rice mill where the initial stages of rough rice transformation take place, and dropped to 2,500 spores/m³ in the last room, where workers are. During a temporary interruption of the working processes, air spora concentration dropped below 1,000 spores/m³.Cladosporium, Epicoccum andNigrospora spores were predominant in all subdivisions of the indoor environments of the rice mill.     

Status of airborne spores and pollen in a coir factory in Kerala,India

The prevalence of airborne fungal spores and pollen grains in the indoor and outdoor environments of a coir factory in Thiruvananthapuram district of Kerala state, India was studied using the Burkard Personal Sampler and the Andersen 2-stage Sampler for 2 years (September 1997 to August 1999). The concentration of pollen grains was remarkably lower than that of fungal spores (ratio of 1:28). There was no large difference in the concentrations and types of fungal spores between the indoor and outdoor environments, with 26 spore types found to be present indoors and 27 types outdoors; of these, 22 were common to both the environments. Aspergillus/Penicillium, Cladosporium, ‘other basidiospores’ and ascospores were the dominant spore types. The total spore concentration was highest in February and lowest in September, and it was significantly higher in 1998–1999 than in 1997–1998. Twenty viable colony-forming types were isolated from inside the coir factory. The most dominant viable fungi isolated were Penicillium citrinum, Aspergillus flavus and Aspergillus niger. The total pollen concentration was higher in the outdoor environment of the coir factory than indoors, with 15 and 17 pollen types, respectively. Grass and Cocos nucifera pollen types were dominant. The dominant spore and pollen types trapped in the two environments of the coir factory are reportedly allergenic and, consequently, workers are at risk of catching respiratory/allergic diseases.     

Occurrence of mites and fungi in the homes of patients with allergic manifestations

This survey was carried out to evaluate mites and moulds concentrations in the homes of patients with allergic manifestations and positive skin-test for mites and/or fungi. The home environments of 277 patients were evaluated by questionnaire, by sampling of airborne fungal spores and by determining the occurrence of mites and moulds in dust samples. Among the 277 patients examined, 83% reacted positively to house dust mites. The fungal allergen most frequently responsible for skin positivity was Alternaria tenuis. The prevalent airborne fungi were Cladosporium, Penicillium and Alternaria, followed by Aspergillus and Aureobasidium. The other genera were found in less than 50% of the homes. The presence of domestic mites in dust was documented in more than 85% of the homes sampled. The occurrence of fungi in dust was generally higher than in the air. The most common genera recovered were Penicillium, Candida, Aspergillus, Aureobasidium, Alternaria and Cladosporium. The homes investigated were divided into two groups, damp and dry, on the basis of the reported presence of wet or damp spots on inside surfaces and moulds growing inside the home. Our results showed that the concentration of mites and moulds in dust was significantly higher (p < 0.01) in damp homes as compared to dry ones.In general, a good agreement between skin positivity and presence of the same allergens in patients' home environment was observed for mites and, among fungi, for Alternaria, Cladosporium and Aspergillus. Our results seem to confirm that the study of mycoaeroflora and the quantification of mites and moulds in dust samples of allergic patients' homes could lead to more precise diagnoses and therefore to better prophylactic and therapeutic programs for each individual patient.     

Enumeration of airborne molds in some indoor environments of Madras city (India) by cultural and non-cultural volumetric samplers

The air mycoflora of six indoor environments in Madras city (India) has been investigated by sampling air with an Andersen sampler and a Burkard personal sampler. Forty-eight species assignable to 24 genera were recorded by Andersen sampler. Spores belonging to 14 genera in addition toPenicillium andAspergillus were identified from Burkard trap slides. Species ofAspergillus, Penicillium, Mucor andRhizopus were most frequently isolated in considerable numbers. As a single genusAspergillus ranked first followed byPenicillium at some sites, andCladosporium at some other sites. The predominance ofPenicillium andAspergillus was also confirmed by Burkard trap data. Spores belonging toGanoderma, Nigrospora, Epicoccum, andTetraploa were recorded only by Burkard sampler, thereby suggesting the necessity of using two complimentary spore traps, cultural and non-cultural, in any aerobiological investigation.     

Detection and identification of moulds in dutch houses and non-industrial working environments

The mycoflora of indoor non-industrial environments is reported from “case” studies in The Netherlands. Both air sampling by a RCS-Reutcr centrifugal air sampler and surface sampling by swabs and cellotape preparations were carried out in homes, archives and libraries, musea, offices and schools. Common species encountered in these indoor environments are Aspergillus versicolor, Penicillium brevicompactum, P. chrysogenum, Cladosporium spp. and the xerophilic fungi Eurotium spp. and Wallemia sebi. Aspergillus fumigatus, Scopulariopsis spp. and Stachybotrys chartarum were occasionally isolated. It is not always possible to detect the mycoflora growing on surfaces by air sampling. Therefore direct microscopical examination and sampling from surfaces in addition to air sampling is strongly recommended for the detection of viable moulds in indoor environments. Selection of the most suitable media for isolation of fungi is discussed.     

The incidence of fungal spores in the ambient air and inside homes: Evidence from London

Little research has been carried out in London concerning fungal spore prevalence yet this information may help to elucidate geographical patterns of asthma and hay fever. Although many types of spore reach peak concentrations outdoors in late-summer, the incidences in the indoor environment may be more important through the winter because of heating and poor ventilation. Daily average concentrations of fungal spores in the ambient atmosphere were monitored with a Burkard volumetric spore trap on an exposed roof in North London from autumn 1991 until the summer of 1992. Indoor spore measurements were taken in 19 homes in the vicinity through the winter months, both by direct air sampling using a portable Burkard sampler and by dust culture. Trends in the occurrence and concentrations of fungal spores indoors and outdoors were examined. Relationships between the abundance of selected allergenic fungi and features of the houses were analysed including age of dwelling, dampness, cleanliness and presence of pets.Aspergillus andPenicillium were the most frequently occurring spore types in the homes. Overall, high spore incidence was associated with dampness and dust accumulation. The outdoor spore samples revealed generally low concentrations through the winter until March when concentrations of many types includingCladosporium, Epicoccum andAlternaria increased in abundance in response to the warmer weather. Even during the late-spring and early-summer, concentrations of most fungal spores were notably below those reported for rural sites.     

Penicillium andAspergillus species in the habitats of allergy patients in the Tulsa, Oklahoma area

Penicillium andAspergillus have been recognized as important aeroallergens for more than 30 years, and are especially significant in indoor environments. There are over 400 species ofPenicillium andAspergillus combined, but there is little information on which species occur most frequently in the environment, or if each exhibits unique allergenic properties. A preliminary study showed no overlap between those species isolated from an outdoor site in Tulsa, Oklahoma and the species used in immunotherapy at allergy clinics in the Tulsa area. Pursuing this line of research, air samples were collected as three seasonal samples (over a 6 month period) in the homes or offices of ten allergy patients known to be allergic toPenicillium and/orAspergillus. Twenty three species ofPenicillium and 12 species ofAspergillus were identified from these samples through isolation, macroscopic, and microscopic examination.Penicillium corylophilum, P. glabrum, Aspergillus niger, andA. flavipes were the most abundant species isolated, supporting the data obtained in a preliminary study. At least in the Tulsa area, it appears that atopic patients are being tested and treated with extracts ofPenicillium andAspergillus species that are either not present or not abundant in the local indoor or outdoor environments. Additional research is necessary to determine if the environmental isolates share allergens with those species used in immunotherapy.     

Peanut-pod mycoflora and kernel infection

Summary The mycoflora in soil clinging to dry pods of peanuts of the Spanish variety Argentine was sampled in 2 experiments by serially washing pods for increasing periods in changes of sterile water. Of the 9 principal fungi found,Aspergillus niger, A. flavus, A. terreus, Rhizopus spp. andSclerotium bataticola were present initially in relatively small numbers and decreased rapidly in subsequent dilutions. This decrease paralleled a decrease in weight of suspended material and in percentage of soil and organic particles greater than 0.016 mm in size.Penicillium funiculosum, P. rubrum, P. citrinum, andFusarium spp. were found in large numbers and increased or slowly decreased in numbers in subsequent dilutions. In some instances variations in numbers followed trends of percentages of soil and organic particles less than 0.016 mm in size.When dry pods with this known mycoflora were allowed to hydrate over a 6-day period at 26°, 32°, or 38°C, there was extensive pod penetration and kernel infection byA. niger, A. flavus, S. bataticola andRhizopus spp. but not by other fungi. The degree ofA. flavus andA. niger infection increased with increasing temperatures.Approved by the Director as Journal Series Paper No. 135.     

The mycobiota from seeds of Shrunken-2 (sh2) Sweet Corn

Sixteen species of fungi were isolated from the pericarp, endosperm, scutellum, and embryo of low (<75% germination), moderate (75–89%), and high vigor (>89%) seedlots of supersweet sweet corn (sh2) hybrids over two years. Most frequently isolated species werePenicillium oxalicum, Rhizopus arrhizus (14.5%), andRhizopus spp (17.4%).Fusarium moniliforme, a common inhabitant in field or dent corn, was isolated from only 2.4% of the samples. The low mean isolation values may be the result of poor conditions for infection or the data may reflect the methods used including sterilization techniques or random tissue selection.Aspergillus niger, F. moniliforme, andP. oxalicum, were isolated at a significantly greater level than other fungi from the high vigor hybrids at 0.89, 0.46 m and 4.46 respectively compared to 0.04, 0, and 1.82 for the low vigor hybrids. When Total Fungi were compared mean isolations were significantly greater from the high vigor hybrids at 11.96, the moderate 8.79, or low 4.86 vigor groups. When data from seed sources for all vigor groups were compared, significantly greater mean isolations were obtained from Illinois Foundation Seed hybrids forCladosporium sp,R. arrhizus, andRhizopus spp., but greater rates were obtained forFusarium oxysporum from the Asgrow hybrids. Isolation frequencies for the 16 species were not significantly different between the seed tissue types from any of the hybrids evaluated during this investigation. Results from this study showed that there is a diverse group of fungi present within thesh2 seed and seed treatments must be developed which will minimize seed rot and seedling blight from both internal seedborne and external pathogens.     

Isolation,identification and testing for allergenicity of fungi from air-conditioned indoor environments

Twelve fungi were isolated and identified from air-conditioned rooms. Of the 12, 7 were species of Aspergillus, viz. A. niger, A. oryzae, A. fumigatus, A. terreus, A. nidulans, A. versicolor and A. parasiticus. Other fungi were Penicillium citrinum, Fusarium oxysporum, Trichoderma viride, Neurospora crassa and Alternaria alternata. A. niger was present in 80% of the locations. Some of the fungi isolated in this study could be opportunistic fungal pathogens, like A. fumigatus, A. niger and Penicillium citrinum, and were found to be allergenic. Results of this study indicate that air-conditioned rooms could be reservoirs of fungi and may cause allergic problems or infections in healthy or immunocompromised individuals living in these environments.     

Fungal spores are an important component of library air

The airborne fungal spore types were studied in different libraries in Delhi, using an Andersen sampler and a Burkard personal sampler, for culturable and non-culturable fungi respectively. The concentration inside the libraries, before and after the agitation of books, were compared with outside air. The major contributors to the library air areCladosporium, aspergilli/penicillia, smuts andAlternaria, varying from 50 to 14%. Some fungi (Cladosporium, Alternaria, smut,Penicillium chrysogenum andnigricans) showed seasonal occurrence, corresponding to their occurrence in the extramural environment. Aspergilli/penicillia,Drechslera, Curvularia andAspergillus flavus had a significantly higher concentration (P<0.01) inside the library, and recorded a significant increase in concentration after agitation of books. Air-conditioned libraries have low fungal spore concentrations, as compared to naturally ventilated libraries.     

Airborne fungi in the hospitals of metropolitan Delhi

Summary The fungal airspora of a large hospital in Delhi Metropolis was studied from May 1989 – April 1991, using Andersen Six Stage Volumetric Sampler and Burkard Personal Slide Sampler. Simultaneously, samples were also collected from outside the hospital to act as a control. Samplers were operated for 10 min. each time, at 10 - day intervals. Additional samples were also collected from different sections of 3 other hospitals. Some of the dominant forms encountered wereCladosporium spp.,Aspergillus flavus, Smut,Fusarium spp.,Aspergillus niger, Alternaria spp.,Penicillium citrinum, Aspergillus versicolor, andPenicillium oxalicum. Aspergillus flavus showed significantly high concentration inside hospital (n=66, x=53 CFU m^–3, p<0.05) as compared to outside air. The peak period for fungi was observed to be from June – September. The spore concentration was much lower in hospital units receiving filtered air as compared to control environment, but in naturally ventilated hospitals the concentration was similar to that of outside air.     

On factors influencing fruit-set and sterility in arecanut (Areca Catechu Linn.)

Summary (1) Histological studies on the stigmas of female flowers of areca indicate the possibility of the stigmatic surfaces being impacted upon by air spora. The presence of spores or hyphae together with pollen grains has been shown in stigmatic surface.(2) Air spora of arecanut plantation chiefly consist ofAspergillus, Penicillium, Actinomycetes, Mucor, Alternaria, Cladosporium andBacteria.(3) The types of fungi, bacteria and actinomycetes adhering to the stigma are isolated.(4) The metabolites of the fungi, bacteria and actinomycetes isolated from the stigmas of arecanut flowers inhibit,in vitro, considerably the germination of pollen grains and rate of growth of pollen tubes. In certain instances there is no germination of the pollen grains in the metabolites of fungi, bacteria and actinomycetes. In view of the results the significance of the air spora in affecting the normal course of pollination and fertilization is discussed.     

Indoor air quality in schools: exposure to fungal allergens

This study examined indoor air quality within schools in Kansas City, Spokane, Santa Fe, and Orlando. Air sampling was undertaken with both Andersen Single Stage Samplers and Burkard Personal Air Samplers. The data show a wide range of indoor exposures ranging from less than 100 colony forming units (CFU/m³) for viable fungi and 100 spores/m³ for total spores in Spokane and Santa Fe to concentrations over 6000 CFU/m³ for viable fungi and 15 000 spores/m³ for total fungi in Orlando and Kansas City, respectively. In the majority of sites the indoor airspora reflected the outdoor taxa withCladosporium the most abundant genus identified; however, several indoor locations had elevated levels ofPenicillium andAspergillus indicating possible sources of indoor contamination. Airborne basidiospores and smut spores were also fairly abundant in the schools and were among the top five taxa identified. The data also indicated that the airborne concentrations vary significantly during the day and between classrooms within each school. Continued studies in schools are needed to fully assess both the exposure levels and the clinical significance to atopic children allergic to these spores.     

Indoor airbornePenicillium species in Taiwan

Penicillium species, well-known indoor airborne fungi, are considered to be important causative agents of extrinsic bronchial asthma. For selecting the proper species for clinical investigations, it is important to know which are found indoors. In the present study, 176 plates of modified Mehrlich's Medium were exposed for 20 min in living rooms and bedrooms of 88 homes in Taipei, Taiwan. A total of 5897 colonies of fungi were isolated, varying from one to 329 per house. Of the total, 910 colonies (15.4%) were identified asPenicillium spp. The three most frequently encountered species wereP. citrinum, P. crustosum andP. implicatum. Penicillium citrinum accounted for 40.5% (369 from 28 houses);P. implicatum, for 5.2% (47 from three houses); andP. crustosum, for 2.1% (19 from seven houses).Penicillium citrinum was judged to be the most prevalent airborne fungus in Taiwan. The allergenic significance of this mold is under further investigation.     

Dispersal of fungal spores from three types of air handling system duct material

Exposure to airborne microorganisms in indoor environments may result in infectious disease or elicit an allergic or irritant response. Air handling system components contaminated by fungi have been implicated in the dispersal of spores into the indoor environment, thereby serving as a route of exposure to occupants. This study was conducted to provide quantitative data on the dispersal of spores from fungal colonies growing on three types of duct material. Galvanized metal, rigid fibrous glass ductboard, and fiberglass duct liner were soiled and contaminated with a known concentration of Penicillium chrysogenum spores. The duct materials were incubated in humidity chambers to provide a matrix of growing, sporulating fungal colonies at a contamination level of 109 colony forming units (CFU) per duct section, consistent for all materials. For each experiment a contaminated duct section was inserted into the air handling system of an experimental room, and the air handling system was operated for three 5-minute cycles with an air flow of 4.2 m3 min–1. The duct air velocity was approximately 2.8 m sec–1. The airborne concentration of culturable P. chrysogenum spores (CFU m–3), total P. chrysogenum spores (spores m–3), and total P. chrysogenum-sized particles (particles m–3) were measured in the room using Andersen single-stage impactor samplers, Burkard slide impactor samplers, and an aerodynamic particle sizer, respectively. The highest airborne concentrations (104 CFU m–3; 105 spores m–3; 104 particles m–3) were measured during the first operating cycle of the air handling system for all duct materials with decreasing airborne concentrations measured during the second and third cycles. There was no significant difference in spore dispersal from the three contaminated duct materials. These data demonstrate the potential exposure for building occupants to high concentrations of spores dispersed from fungal colonies on air handling system duct materials during normal operation of the system.