The pictures that comprise this image were taken in parkland, in Queensland, in a wet, humid area. These conditions are ideal for the growth of environmental fungi. Fungal organisms are indispensable in the natural ecosystem and to life on this planet. They benefit humans, plants and animals, but they also interact in pathological ways. Of the many thousands of identified fungi only a dozen or so are “life-threatening” to humans, indeed many benefit humans such as penicillin. There are very few “primary” human fungal pathogens, e.g. coccidiomycosis and histoplasmosis.
Fungi can however cause devastating disease in plants and animals, though very few can do both. Cryptococcus gattii is one that infects both humans and animals but is non-pathogenic in plants. Humans are largely resistant to fungal disease, possibly due to the high basal temperature of mammals which fungi do not like.
The incidence of fungal disease in humans is however increasing, most likely due to the growing population of immuno-compromised people e.g. people who have received organ transplants, people on long term steroid treatment, and of course HIV/AIDS, and once established these diseases are difficult to treat.
The X-ray, which is hardly visible in this image, is from a woman who contracted Cryptococcus gattii in South-East Asia. This causes a deadly infection of both lung and brain. It was initially a disease of tropical and sub-tropical regions of Asia and Australia but is recognized as an emerging disease in Canada.