Can you help identify this unknown pathogen?

A protist found in the brain of a sick green and gold bell frog tadpole


We have recently run this intriguing query on our main Microscopy UK Index but we are also pleased to display it in Micscape this month. If you can offer any help, please contact Rick Speare as suggested below. Thanks!


Rick Speare of the School of Public Health and Tropical Medicine, James Cooke University, Australia writes:

I have an image of an unknown pathogen that I would very much appreciate you putting in Micscape for comment by experts. This was made by my colleague and PhD student, Dr Lee Berger. Lee and I work together on amphibian diseases and declining frogs in Australia.

TEM of protist in the brain of a sick green and gold bell frog tadpole, Litoria aurea, from Taronga Zoo, Sydney, Australia.

Click here for 1181x791 pixel 215kByte master image.

Scientist: Dr Lee Berger, CSIRO Australian Animal Health Laboratory, Geelong.


Problem: We have been unable to identify what the microorganism is apart from calling it a "protist". It did appear to be pathogenic to the tadpole.

Questions: Does anyone know what it is? Has anyone seen something similar - even if they do not know the identity?


Rick Speare
School of Public Health and Tropical Medicine
James Cook University
Australia 4811

Visit the amphibian diseases home page at James Cooke University.


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