ABSTRACT
Fungal elements represent a significant part of the biological contaminants that could be detected in the air of animal facilities. The aim of this study was to assess the relative efficiencies of two air sampling methods and three culture conditions for the quantification of airborne culturable fungi in a poultry farmhouse in France. Air samples were collected every week throughout a 15-week period. Two devices were simultaneously used-a rotative cup air sampler (CIP 10-M, Arelco, France) and an air sampler based on filtration (AirPort MD8, Sartorius, Germany). Culture of airborne viable fungi was performed on malt extract agar (ME) and dichloran glycerol-18 (DG18) at 25 or 37°C. CIP 10-M and AirPort MD8 were shown to display comparable performances but significant differences were observed between culture conditions for Aspergillus spp. (p<0.01), Scopulariopsis spp. (p=0.02) and unidentified molds (p<0.01).
Subject(s)
Air Microbiology , Air Pollution, Indoor/analysis , Environmental Monitoring/methods , Fungi/growth & development , Alternaria/classification , Alternaria/growth & development , Alternaria/isolation & purification , Animal Husbandry , Animals , Aspergillus/classification , Aspergillus/growth & development , Aspergillus/isolation & purification , Cladosporium/classification , Cladosporium/growth & development , Cladosporium/isolation & purification , Colony Count, Microbial , Culture Techniques , Environmental Monitoring/instrumentation , France , Fungi/classification , Fungi/isolation & purification , Mycological Typing Techniques , Penicillium/classification , Penicillium/growth & development , Penicillium/isolation & purification , PoultryABSTRACT
Information obtained from fungal air samples can assist in the assessment of health hazards and can be useful in proactive indoor air quality monitoring. The objective of the present study was to evaluate the PCR-TTGE technique for the analysis of fungal diversity in the air. Eleven air samples were collected in five different sites using the bioimpactor CIP 10-M (Arelco). After a 2 hours sampling period, the collection liquid was recovered for subsequent cultivation and PCR-TTGE. A set of three fungi-specific primers (Fungcont 1, Fungcont 2+GC and Fungcont 3) was designed for the partial amplification of the 18S rRNA gene. The amplification was obtained in a single reaction tube by a semi-nested PCR. For identification, the TTGE bands were extracted and sequenced. PCR-TTGE allowed the clear separation of amplicons corresponding to distinct fungal species (both Ascomycota and Basidiomycota) that may be encountered in air. The number of fungal taxa detected after culture was systematically higher than the number of taxa found using PCR-TTGE. However, few fungal species were detected by PCR-TTGE and not by cultivation, suggesting that the combination of these approaches may provide a better analysis of fungal diversity in air samples than either method alone.
Subject(s)
Air Microbiology , DNA, Fungal/genetics , Electrophoresis, Polyacrylamide Gel/methods , Fungi/classification , Polymerase Chain Reaction/methods , Aerosols , Biodiversity , DNA, Fungal/isolation & purification , DNA, Ribosomal/genetics , DNA, Ribosomal/isolation & purification , Fungi/genetics , Fungi/growth & development , Fungi/isolation & purification , Hot Temperature , Nucleic Acid Denaturation , RNA, Ribosomal, 18S/genetics , Sequence Analysis, DNAABSTRACT
To date, investigations of Pneumocystis jirovecii circulation in the human reservoir through the dihydropteroate synthase (DHPS) locus analysis have only been conducted by examining P. jirovecii isolates from immunosuppressed patients with Pneumocystis pneumonia (PCP). Our study identifies P. jirovecii genotypes at this locus in 33 immunocompetent infants colonized with P. jirovecii contemporaneously with a bronchiolitis episode and in 13 adults with PCP; both groups of patients were monitored in Amiens, France. The results have pointed out identical features of P. jirovecii DHPS genotypes in the two groups, suggesting that in these groups, transmission cycles of P. jirovecii infections are linked. If these two groups represent sentinel populations for P. jirovecii infections, our results suggest that all persons parasitized by P. jirovecii, whatever their risk factor for infection and the form of parasitism they have, act as interwoven circulation networks of P. jirovecii.
Subject(s)
Dihydropteroate Synthase/genetics , Pneumocystis carinii/enzymology , Pneumonia, Pneumocystis/microbiology , Adult , Aged , Female , Genotype , Humans , Immunocompetence , Immunosuppression Therapy , Infant , Male , Middle Aged , Polymerase Chain Reaction , Retrospective StudiesABSTRACT
Pneumocystis jirovecii ITS and DHPS genotypes were identified in 3 patient groups developing diverse forms of P. jirovecii infections: 13 patients with Pneumocystis pneumonia, 8 patients merely colonized by the fungus, and 19 immunocompetent infants with bronchiolitis developing mild P. jirovecii infection. Common P. jirovecii genotypes were found in the 3 patient groups, suggesting that common sources of P. jirovecii were involved in the fungus acquisition, and that transmission cycles of P. jirovecii infections in these patient groups are not independent. Parasitized patients, whatever the form of parasitism they present, may be part of a common reservoir for P. jirovecii.
