Rats!!! I think you have Tuberculosis

Gambian pouched rat before ID rounds

We recently reported that the WHO endorsed the use of Cepheid's rapid TB test that carries a $17,000 fixed device cost and $17/test cost in developing countries.  The device would cost $64,000 in the US.  In yesterday's NY Times there was an article discussing a recent report in The American Journal of Tropical Medicine and Hygiene by Alan Poling at Western Michigan University that found that the Gambian pouched rat was far better than standard microbiological tests for TB diagnosis. In 10,523 patient, the rats trained to smell the sputum samples found 44% more cases. Sensitivity was reported as 86.6% and specificity was 93%.

Wow.  I hope these results can be validated in other settings.  If these rats are equally or more accurate than standard or rapid TB tests with minimal costs, there is no reason why they would have to be limited to resource-poor settings, right? Compared to a $64k rapid test plus test costs, I bet the rats would be very cost-effective; especially if they are more effective. It would be pretty cool to see ID clinicians carrying 15 pound rats around with them on rounds. 

Poling A. et al AJTMH, December 2010
NY Times article, January 3, 2010