If we can contain and monitor animal viruses at an earlier stage - when they're first entering human populations, preferably before they've had a chance to become human-adapted, certainly before they've had a chance to spread - we can head off pandemics altogether.
The reality is: By the time swine flu got on the radar screen of global public health, it had already spread. It was already in the States, it was in Mexico, it was in New Zealand. By the time it reaches that point, you've lost the ability to contain it.