A patient being tested for bacterial infection. Source
One problem with identifying bacterial infections is that samples must be taken, grown in a culture, and finally exposed to various antibiotics in order to identify which bug has gotten into a person. New research, however, is working on identifying these bacterial infections by their "smell" in a person's breath. Bacteria in lung infections produce certain chemicals that are present in breath and even get exhaled themselves, this new research is using complex and sensitive machines to identify these footprints. There are still some challenges to overcome, but if all goes well we could be diagnosing ailments much, much faster.
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