Dusts containing H. capsulatum spores can be aerosolized during construction, excavation, and demolition. Once airborne, spores can be carried easily by wind currents over long distances. Such contaminated airborne dusts can cause infections not only in persons at a work site, but also in others nearby. Such activities were suggested as the causes of the three largest outbreaks of histoplasmosis ever recorded. All three outbreaks took place in Indianapolis, Indiana during the fall of 1978 and the spring of 1979. An estimated 240,000 people were infected, and 30 people died. AIDS patients accounted for nearly 50% of culture-proven cases. Water sprays or other dust suppression techniques should be used to reduce the amount of dust aerosolized during construction, excavation, and demolition in regions where H. capsulatum is endemic.
During windy periods or other times when typical dust suppression techniques are ineffective, earth-moving activities should be interrupted. All earthmoving equipment (e.g., bulldozers, trucks, and front-end loaders) should have cabs with air-conditioning (if available) to protect their operators. Air filters on air-conditioners should be inspected on a regular schedule and cleaned or replaced as needed. During filter cleaning or replacement of exceptionally dusty air filters, respiratory protection should be worn. Water sprays and other suppression techniques may not be enough to control dust aerosolized during demolition of a building or other structure.
Consequently, removal of accumulations of bird or bat droppings before demolition may be necessary in some situations. Factors affecting decisions about pre-demolition removal of such accumulations include the quantity and locations of the material, the structural integrity or soundness of the building, weather conditions, proximity of the building to other buildings and structures, and whether nearby buildings are occupied by persons who may be at increased risk for developing symptomatic histoplasmosis (e.g., schools, day-care facilities, hospitals, clinics, jails, and prisons.)