Killer fungus that grows on trees

A teenaged girl has helped scientists discover that a deadly fungus that generally attacks HIV/AIDS patients grows on trees.

As part of her science project, Elan Filler, 13, spent the summer gathering soil and tree samples from areas around Los Angeles.

Her father Scott Filler, an infectious disease specialist at University of California, Los Angeles, helped her send the samples to Duke University School of Medicine for analysis.

The samples were analysed in the lab of Deborah J. Springer, a postdoctoral fellow at the Center for Microbial Pathogenesis at Duke University's School of Medicine.

Springer was surprised to find that three of the tree fungus specimens were genetically almost indistinguishable from the cryptococcus gatti specimens she had seen in AIDS patients.

Cryptococcus is a family of fungus that causes life-threatening infections of the lungs and brain and is responsible for one third of all AIDS-related deaths.

"Three tree species - Canary Island pine, Pohutukawa and American sweetgum - can serve as environmental hosts and sources of these human infections," Springer added.

"We had thought it would be fun to send her (Elan) out in search of fungi living in the greater Los Angeles area," she added.

"People who visit areas like California, the Pacific Northwest and Oregon need to be aware that they are at risk of developing a fungal infection," Springer cautioned.

The study appeared in the journal PLOS Pathogens.