The use of formalin to kill Histoplasma capsulatum at an epidemic site.

Early attempts to eliminate Histoplasma capsulatum from known positive sites were either unsuccessful or rendered the soil unfit for growth of vegetation (1, 2). Recently, formaldehyde solution (formalin) and cresol compound have been shown to be effective decontamination agents in the laboratory and in field experiments under natural conditions (3). The promising results with formaldehyde solution led to its large-scale field trial to decontaminate a 5-acre site in Mason City, Iowa, which had been the source of 2 epidemics of histoplasmosis (4, 5). The present paper describes the methods used and the results of the decontamination project.