What if there’s a sudden, massive flu outbreak and people need to get a vaccine fast? How quickly can Colorado health officials respond? It’s a question — and a scenario — Colorado began preparing for three years ago. Saturday, officials put their plan to the test.

Forty-five minutes after the first needle was plunged into a Coloradan’s arm Saturday, more than 6,000 people statewide had received flu shots in an exercise to prepare for a large-scale flu outbreak. The exercise by the Colorado Department of Health and Environment targeted 26,000 people throughout the state at 28 sites, including a parking lot at Coors Field. “We expect to have at least 20,000 shots given by noon,” said Katherine Davis, spokeswoman for the health department.

That’s good news. And a reminder, this is going to be a bad year for the flu. So don’t forget to get your shot.