All that data on all those people she was in contact with ... and no idea where she contracted it. But if one little detail comes to light, it could connect all the dots... and lead to an entirely different population of infected.
Did she stop at a food cart and buy an apple? or a coffee? Use a public restroom in a busy place like a train station? Man... working the data on an epidemiological outbreak must be fascinating, electrifying, and terrifying.