Jo Anna,
This had to look up online:

Caged birds (parrots, canaries, etc.):
Low to moderate risk
A regularly cleaned indoor bird cage usually does not create ideal conditions for this fungus.
* Risk increases if:
* Droppings accumulate for long periods
* The material dries out and becomes airborne dust
* Cleaning involves sweeping or scraping without dampening

Smart precautions:

* Lightly mist surfaces before cleaning (prevents dust)
* Use gloves and a mask (even a simple one helps)
* Avoid dry sweeping or vacuuming droppings
* Wash hands well afterward

Chicken and Coops:
Higher risk of transmission than caged birds—but still situational.

* Histoplasma is more associated with soil contaminated by bird or bat droppings over time, not the birds themselves.
* Chicken coops can become a concern when:
* Droppings build up in soil or bedding
* Areas stay shade and undisturbed
* Old material becomes dry and dusty, then gets disturbed

Mexico - Histoplasmosis does exist in parts of the country, particularly in rural areas, caves, old buildings, and places with bird/bat accumulation
* Backyard chickens can contribute to the right conditions, but they are not the primary source (bats are often more implicated)

Smart precautions:

* Wet down the coop/ground before cleaning
* Wear a mask (ideally N95 if lots of dust) and gloves
* Avoid stirring up dry, dusty manure
* Clean regularly to prevent buildup
* If possible, improve ventilation and sunlight exposure

So the bottom line:

* Caged birds: very low risk if you clean routinely and avoid dust
* Chickens/coops: moderate risk only if droppings accumulate and become dusty
* The real issue is inhaling spores from contaminated dust, not the animals themselves

Hope that helps! I learnt a lot too!