Anyone who has ever noticed that a sick person can sometimes have bad breath will be interested to learn that this concept has been translated into real-world diagnostics:
Recently, a group of researchers from the University of Vermont saw this idea [a breathalyzer detecting blood alcohol levels] and had another: What if a device could be designed to detect a chemical signature that indicates a bacterial infection in someone’s lungs? Their result, revealed yesterday in the Journal of Breath Research, is a quick and simple breath test—so far used only with mice—that can diagnose infections such as tuberculosis.
In their study, they focused on analyzing volatile organic compounds (VOCs) in mouse breath to distinguish between different strains of bacteria that were infecting the animals’ lungs. They hypothesized that these bacteria produce VOCs not normally present in the lungs, thus allowing their test to differentiate between a healthy animal and a sick one.
[…] Their test was a success: There was a significant difference between the chemical signatures of healthy and infected mouse breath, and their test was even able to indicate which type of bacteria were the source of the infection.
Fabulous. Go to your doctor, blow into a breathalyzer and get near-instant results (as opposed to culturing bacteria for testing, which can take days to weeks). This has great potential.
It should have been on Star Trek.


This phenom is a reason some dogs trained to do so can pick up on certain human illness through smelling the persons breath and or body scent.
Good point! I hadn’t thought of that, but now that you mention it I remember reading something about dogs being trained to sniff out one of those awful hospital-induced infections…the one that kills so many people who otherwise should have been fine. Apparently the dogs’ accuracy rate is better than lab tests, and of course it’s instant.
Apparently they can also detect cancer. (if memory serves)