Today, the University of Colorado at Boulder made an announcement regarding a very promising technology:

Known as optical frequency comb spectroscopy, the technique is powerful enough to sort through all the molecules in human breath and sensitive enough to distinguish rare molecules that may be biomarkers for specific diseases

Combined with other rapid-response technologies, this could be part of the detection side of a BioShield, a technological immune system for humanity.

The optical frequency comb is a very precise laser for measuring different colors, or frequencies, of light, said Ye. Each comb line, or “tooth,” is tuned to a distinct frequency of a particular molecule’s vibration or rotation, and the entire comb covers a broad spectral range — much like a rainbow of colors — that can identify thousands of different molecules.

Source: University of Colorado at Boulder