Almost 5000 people die from tuberculosis every day and drug -resistant TB is spreading quickly to alarming levels.  In sub-Saharan countries, fewer than 50% of existing TB cases are currently detected.  In addition to the harm caused to her or him, each person whose TB is not detected and treated infects an average of 10 to 15 other people per year.

Case detection in developing countries mainly depends on smear microscopy, a slow and unreliable technology that has not changed over the last 100 years.  Despite major research efforts worldwide, no new diagnostic method for TB has provided the combined virtues of speed, accuracy and reliability.

But APOPO has provided proof of principle that rats can do the job.  They are fast, reliable and cheap.  In less than 10 minutes on rat evaluates the same number of samples a microscopist can handle in a full day.   And the rats work with high accuracy and sensitivity.  The ongoing APOPO Rat Detection Program, in which rats analyze samples provided by collaborating TB clinics, has increased the TB detection rate in patients of those clinics by more than 30% - and the rats’ speed and high throughput result in a cheaper diagnosis.  Although some are sceptical of “Doctor Rats,” APOPO’s standardized, out of the box method for detecting TB is rapidly gaining acceptance in view of such promising results, which are being reported in scientific journals, as well as in the news media.

As a screening tool, the rats could be used for pro-active case finding, or in combination with more expensive or slower methods, to screen out the bulk of negative samples, which are a major burden to the reference labs.  Both of these applications are invaluable weapons in the struggle against TB.