Decontamination of a Histoplasma capsulatum-infested bird roost in Illinois.

Histoplasma capsulatum was isolated from 27 of 34 soil specimens collected from a 3.23-hectare (8-acr) estate in illinois that had been the site of a bird roost for more than 10 yr. When the estate was sold to a developer for for the construction of a shopping center, it was feared that disturbing the roost would cause airborne transmission of spores of H. Capsulatum and thus create a public health hazard for the workmen and surrounding community. To prevent this, the bird roost was decontaminated with the application of 3,785 ml (1 gallon) of 3% formalin per square foot of soil. Safety precautions were taken to minimize the inhalation of dust and formalin by the decontamination team. Thirty-five soil specimens collected after application of the formalin were negative for H. capsulatum. No cases of histoplasmosis occurred among the decontamination workers, construction crews, or the general population. The total cost of the decontamination project was $75,000.