It turns out that viruses evolve from each other, like everything else. So if you look at the evolutionary tree of viruses, you can find parts of their genome that haven't changed over evolutionary time. You can recognize what may be a new virus by identifying this little piece of their genome that hasn't changed and is represented on the chip.
When I came to University of California, San Francisco to work on infectious disease, I looked around to different options, and malaria was particularly interesting and fascinating to me. It's amazing that after 100 years of study of this little parasite, we've not been able to effectively control it.
Surveying the way viruses have been discovered in the past, I came to the conclusion that I could use my technology that I developed as a graduate student - DNA microarray technology - to create a chip that would simultaneously screen for all viruses ever discovered, and furthermore have the built-in capability of discovering new viruses.