Friday, October 28, 2011
Do all Cordyceps grow on insects? - Part 2
In the post “Do all Cordyceps grow on insects?” (August 7, 2011) I briefly mentioned that some insect fungi can infect humans. I casually made comparison to the movie Alien where an alien developed in the character played by John Hurt and then burst out of his stomach - yuk. Bahra made a comment to this post asking if the fungus can make use of us by producing a mycelium and spreading spores.
The insect fungi that have opportunistically 'attacked' us struggle to grow much above 35C. As a result they do not form deep-seated mycoses. When they do infect they infect skin and eyes mainly. The cornea appears to be a particular favourite. Purpureocillium lilacinus (formerly known as Paecilomyces lilacinus) is the most well-known of this group.
I don't think anyone has looked at whether these infections can propagate themselves on humans by developing and spreading spores. However, I think I can safely say that they could not result in an epidemic in human society. They are 'nuisances' for immuno-compromised individuals.
Luangsa-ard, J.J, Houbraken, J., van Doorn, T., Hong, S.B., Borman, A.M., Hywel-Jones N.L. & Samson, R.A. (2011). Purpureocillium, a new genus for the medically important Paecilomyces lilacinus. FEMS Microbiological Letters. 321: 141-149.