APOPO rats

Magawa, The Heroic Landmine-Sniffing Rat, Has Died

The hardworking rodent found more than 100 mines and other explosives in Cambodia, and was awarded a prestigious medal for his lifesaving efforts.
By 

These Rats Can Detect Tuberculosis With Almost 100% Accuracy

A trained rat can screen 100 samples in 20 minutes.
By Kizito Makoye, Reuters