Histoplasma capsulatum will grow in soil enriched by bird droppings (guano). Before disturbing an area contaminated by bird droppings in a region endemic for histoplasmosis it may be necessary to perform environmental sampling with culture to determine if and where decontamination may be required.


Area in Square Feet

Number of Sampling Areas

Area for Each Sample

< 100


< 50

100 – 399


25 - 100

400 – 899


67 - 150

900 – 7,199


75 - 600

7,200 – 14,400



14,401 – 28,800



28,801 – 57,600



>= 57,601




Sampling of area <= 7,199 square feet: A single specimen should consist of small soil samples are taken at many points throughout the area.


Sampling of area >= 7,200 square feet: A single specimen should consist of small soil samples taken from an area 2 feet in diameter. These are taken from points designated on the survey map at standard intervals. These can be marked for later repeat resampling.


General instructions for sampling:

(1) Workers should wear respirators and other personal protective equipment as needed.

(2) A survey of the area should be performed with each collection site designated. This same survey will be needed for environmental samplings before and after decontamination.

(3) Top litter should be removed, with samples taken of the top 1-2 inches of soil and guano.

(4) Each specimen should be collected using a sterile spoon or scoop to collect soil into a sterile bag or container.

(5) A separate sterile collection tool should be used for each collection area.

(6) Each specimen should be properly labeled with the site and time of collection designated.

(7) The specimens are sent to a laboratory experienced in fungal isolations.


Timing of samples in a contaminated area:

(1) initial, before decontamination

(2) 1 month after decontamination

(3) 2 months after decontamination

(4) 3 months after decontamination

(5) 6 months after decontamination

(6) 1 year after decontamination


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