“A friend of mine once said the way to stop smoking is to close your eyes, think about the person you dislike the most,” Bloomberg, 75, told me. “Now, do you want to be at their funeral or you want them to be at yours?”

He was making a point about how difficult it can be for people to change their behavior, which is a big part of foiling noncommunicable diseases. It’s also one reason those diseases don’t always generate the concern that something like Zika or Ebola does. They’re regarded as the sufferer’s fault.

There are other reasons, too. A communicable disease can spread fast and far and kill indiscriminate of age.

But heart disease, respiratory ailments and diabetes — all among the world’s top 10 causes of death — also end the lives of many people still in their prime. And they’re often abetted by environmental factors within government’s influence.

We’ve used taxes to lessen the appeal of cigarettes and can take a similar approach with sugary beverages. We can construct parks and bike lanes.

We can clean the air. We can improve road safety; traffic injuries were the 10th leading cause of death globally in 2015, according to the World Health Organization.

Bloomberg is advocating all of this in a new role as the W.H.O.’s global ambassador for noncommunicable diseases. And his charitable organization’s Partnership for Healthy Cities provides money and other support to local governments around the world that implement policies to prevent noncommunicable diseases, road injuries or both. A decade ago, his organization funded two programs along these lines; now it funds nine. He has committed more than $800 million over the next six years to these efforts.