Aspergillus Air Pollution in Operating Theatres

Aim of this paper is to present the results of a survey, performed in a teaching hospital of Rome, in order to evaluate the fungal air pollution of operating theatres (OTs) in which also high risk patients underwent an operation. The study was performed in 14 OTs. In each OT, 9 air samples were collected, using an active sampler SAS-PBI. Rodac plates with Sabouraud cloramphenicol and nutrient agar were used; the CFU were counted after incubation for 48h at 37°. Eight (57%) OTs showed at least one sample positive for Aspergillus. 12 (9,5%) of the 126 samples collected were positive. 33,4% of positive samples were collected near the air conditioning system outlet (A. fumigatus, A. flavus, A. niger) and a further 33,4% near the surgical table (A. niger, A fumigatus, A. nidulans, A. flavus). The remaining strains were isolated away from such critical places. All Aspergilli isolated were thermo-resistant. INDEX TERMS Aspergillus, air pollution, operating theatres, monitoring, pathogenicity INTRODUCTION In the last two decades several studies have shown an increase of hospital infections due to opportunistic fungi (Fraser et al, 1979, Pertowski et al, 1995, Groll et al, 1996). The most frequently involved species are Candida (Pfaller, 1988) and Aspergillus (Bodey and Vartivarian, 1989). The rising incidence of these infections is mainly due to the widespread use of aggressive cancer chemotherapy regimes, the increasing number of transplant programs and the occurrence of AIDS epidemic (Bodey, 1988, Drohuet E, 1989, Manuel and Kibbler, 1998). Despite the development of new therapeutic approaches there infections are still responsible for a high mortality that exceeds 50% of cases (Hospenthal, 1998); therefore it is important to introduce effective control measures to avoid further risks for patients. Aspergillus spp are common environmental saprophytes, often found in soil, water, fomites, ventilation systems, building materials, potted plants and other sources like foods. Aspergillus species account for up to 40% of the fungal flora in hospital and home environment (Manuel and Kobbler, 1998). There exist about 180 Aspergillus species and about 30 of them are potentially pathogens for man and animals; in particular: A. fumigatus, A. flavus and A. niger (Chabasse et al, 1995). * Contact Author: [email protected] Proceedings: Indoor Air 2002