Did you have any sense of what you wanted to do in the field of health?

I wanted to be in public health. I went to Calcutta, India, after my first year of medical school, and then I went to Africa a few other times. And I really began to think about how to impact public health on a large scale. Somewhere in the journey, I decided that I did not want to impact health by working with individual patients. I wanted to have a bigger impact on populations. The question was: Do you do that through public health? Do you do that through private business?

So you decided to join McKinsey. What happened?

I promptly got put on M&A projects. That’s what happens. And I had an aptitude for translating medicine into valuation models. It was a skill set that I still use today. Frankly, the fact that I can build my own model is something useful in a job like this. I don’t want to criticize McKinsey. It’s often portrayed that I was at McKinsey for an extended period of time. I was there for about 18 months.

You’ve had a variety of roles at Novartis. Which were the most formative?

The real trial by fire for me was leading our response to the H1N1 pandemic in 2009. Novartis had become the largest supplier of H1N1 vaccines to the U.S. government. We were behind, as were all companies, because we were trying to develop these vaccines in, like, six months, something that usually takes about six years. We were far enough behind that I was on calls with Kathleen Sebelius, the health secretary, and the White House, under huge amounts of pressure to figure out how to make this all happen.

It became clear that the only way to get the organization to deliver 150 million doses of vaccines was to inspire people. It was such an audacious thing to try to get all of this done. And in the end we did pretty well. We were only a couple of months later that we needed to be to get the full supply in.

Did that experience leave you hopeful or concerned about our ability to respond to a pandemic?

I remain deeply concerned. In that instance we were incredibly fortunate that the virus was not deadlier. But I think we are not at all prepared for a pandemic.

There are a couple of challenges. One is that the industry cannot make it financially sustainable to have the capacity to be ready for a pandemic, because it just sits idle . But the governments lose interest, right? So you have to invest in the long run from a public sector standpoint. If there are no pandemics for a while, then people don’t want to invest in this. So I think that remains a challenge, whether it’s pandemic influenza, Ebola, Lassa fever, Zika. We are ill prepared, and are just dodging bullets .

You’re relatively young to be the C.E.O. of such a large company. How did you prepare for the role?

I spoke quite a bit with other C.E.O.s and former C.E.O.s. I remember one of them telling me that the larger organizations will fight change through all of their inherent systems. Whether they realize it or not, organizations will resist really fundamental change. Another one said, “Be careful. Everyone’s going to try to kill your dreams.”