Nobody ever thanks you for saving them from the disease they didn't know they were going to get.
Vaccines are the tugboats of preventive health.
People are beginning to understand there is nothing in the world so remote that it can't impact you as a person. It's not just diseases. Economists are now beginning to say if we are going to have good markets in Africa, we're going to have to have healthy people in Africa.
Science is beginning to catch up with global health problems.
Finally, develop tenacity and an optimistic outlook. It doesn't mean that everything will always work out or that you won't suffer. But pessimism seems to be designed to force you to suffer before the fact!