Is the histoplasmosis an occupational hazard between the investigators who perform field work?

Abstract

Histoplasmosis is a systemic mycosis caused by Histoplasma capsulatum. Human infection occurs by inhaling the microconidia found in soil contaminated with birds and/or bats excrements. In this study, the potential risk of infection with Histoplasma from practicing professional activities in caves was emphasized. Information on the fieldwork conducted by a group of 15 biologists were obtained through a semi-structured questionnaire; and the presence of antibodies anti-H. capsulatum was evaluated in their serum samples. The data analysis showed that 87% of subjects reported the frequent cave exploration, 53% camping inside the caves, 33% bats capturing activities, and 53% soil samples collection. The majority of the caves are located in the Southeast and Midwest regions of Brazil. By using double immunodiffusion assay, 20% of sera reacted with H. capsulatum antigen. By immunoblotting, it was found 94.1% of specific recognition of 94 kDa fraction, suggesting that the individuals had contact with the fungus. This study strongly suggests that the individuals practicing speleology were prone to fungal species exposure, which inhabit the environment as saprophytes, especially H. capsulatum, and it might characterize a potential risk factor for infections.