She says, when it comes to infectious diseases, General Hospital is as real as it can get.
"When I go to the hospital, I keep an inventory of the problems that I am seeing amongst our patients. The vast majority of those problems are exactly the kinds of things the CDC is trying to prevent."
This year, Gerberding is seeing an alarming number of patients with drug resistant staph infections.
"On my first day, almost all of my patients had staph infections. I've seen patients with e-coli, a particular bacteria that is resistant to almost every antibiotic we have in the hospital."
She worries that a deadly bacteria will eventually develop with no first line treatment.
Gerberding spent 17 years here, treating the first AIDs patients, then as head of epidemiology.
As the director of the CDC, she is always reminding people the epidemic if still very much alive. Last May, she was in Oakland, encouraging people to get tested.
"We used to think, 'oh, we are just buying time until that vaccine is here'. Well, I don't see that vaccine anytime soon and I think we have to now adjust in a dramatic way and say prevention is the vaccine."
Gerberding also spent her time visiting some of the Healthy San Francisco clinics to see what's working and what's not, and saw a model for medical respite that cares for the homeless after getting out of the hospital.
On a larger scale, Gerberding has been working on potential health crisis -- the threat of bioterrorism.
"I don't see anything in the world that tells me that those threats are any lower today that they were five years ago."
She assured us, there is more than enough small pox vaccine for everyone in America, but admits, in the event of an anthrax attack, getting the right antibiotic to everyone, within 48 hours of exposure, is still a challenge for the CDC.
It's always on her mind, but this week, San Francisco has been -- the city and its most vulnerable.