Day 7: 6:00 AM - 7:00 AM - S7-E23
Factual error: The head scientist tells Tony that the pathogen can survive 2 hours and longer after to host's death. Assuming it is either virus or prion (a protein), it wouldn't be alive to begin with and could effectively remain in Jack's body indefinitely.
Answer: According to Jack in season 5, Nina was "deep cover" before the pair ever met, so it's safe to assume she was recruited before she joined CTU. As for what her primary mission was, who knows? Perhaps it was to gather sensitive intel and pass it on to her superiors. Given that she worked for an intelligence agency, it's not a stretch. Or perhaps we may find out in season seven.
Cubs Fan ★