There are still the "deniers" out there who keep parroting the "don't panic" line from the CDC. A recent article even linked "panic'ers" with low math and science skills.
For the record. I have 12 credit hours each of math and chemistry from Georgia Institute of Technology, as well as 12 credit hours of statistics from University of South Florida and Georgia State University. I don't think I'm in the "low math and science skills" category. I'm not panic'd, but I am concerned with our government's handling of the current crisis and it's ability going forward.
The question then is: When is it time to panic?
I couldn't find a clear and concise chart from the CDC, but I took the following (with some editing) from World Health Organization. You might want to customize it as you see fit. This is from a white paper titled, WHO global influenza preparedness plan and while it was mainly addressing influenza virus I think it could be appropriately used with any transmittable malady.
I think we're on Phase 3 bordering on going Phase 4. I believe the time to prepare is now and the time to panic is when we are at full Phase 4 going to Phase 5.
Interpandemic Period
Phase 1. No new subtypes have been detected in humans. A subtype that has caused human infection may be present in animals. If present in animals, the risk of human infection or disease is considered to be low.
Phase 2. No new subtypes have been detected in humans. However, a circulating animal subtype poses a substantial risk of human disease.
Pandemic Alert Period
Phase 3. Human infections with a new subtype, but no human-to-human spread, at most rare instances of spread to a close
contact.
Phase 4. Small clusters with limited human-to-human transmission but spread is highly localized.
Phase 5. Larger clusters but human-to-human spread still localized, (substantial pandemic risk)
Pandemic Period
Phase 6. Pandemic phase: increased and sustained transmission in general population.