New approach to study the real exposure to fungi in cork industry: nasal swabs mycobiota investigation coupled with screening on fungal resistance to azoles

摘要

The permanent contact with cork may lead to constant exposure to fungi, raising awareness as a potential occupational hazard in the cork industry. In fact, the presence of fungi belonging to the Penicillium glabrum complex has been associated with the development of respiratory diseases such as suberosis, one of the most prevalent diseases among workers from cork industries, besides occupational asthma. The aim of this work was to characterize fungal distribution and to evaluate the incidence of isolates resistant to azoles present in nose swab samples from the cork industry workers. Nose swab samples were collected from 305 workers from two cork industries. Samples were plated onto malt extract agar (MEA) media (for morphological identification of the mycobiota present) and also onto screening media of Itraconazol and Voriconazol (to detect azole-resistant Aspergillus isolates). Plates were incubated at 27°C during 5 to 7 days. Using macro- and microscopic analysis of the colonies, fungal contamination was evident in 267 from the 305 samples collected (87.5%). From 267 contaminated samples, 109 presented countless units of Chrysonilia sytophila (40.8%). The most prevalent genus found was Penicillium sp. (73.6%), followed by Cladosporium sp. (9%), Chrysonilia sp. (2.9%) and Acremonium sp. (2.6%). From the 305 samples collected, 161 belong to workers from the cork yard. Penicillium sp., Cladosporium sp., Acremonium sp. and A. niger complex were the most commonly found species. Itraconazole resistant isolates of the Aspergillus genus were found in nose samples from two workers of the cork yard, belonging to the Nigri and Fumigati sections. This approach allowed knowing the real contact with fungi of the workers of cork industry. Additionally, was possible to obtained data regarding the fungal mycobiota present that can result in negative health effects. Ongoing studies on this population are being performed in order to assess possible health implications related to fungal exposure in this occupational setting.