Every company is in the health care business, no matter its industry. So says John Quelch, a professor at both the Harvard Business School and the Harvard T.H. Chan School of Public Health, where Quelch has devoted an entire class to the intersection of business and health care called “Consumers, Corporations and Public Health.” The course uses cases on a wide range of subjects, from HealthCare.gov to Royal Caribbean Cruises, to medical marijuana, to dig into issues of corporate strategy, employee safety, and how to solve health problems through research and innovation.