The concept is lost, due to a lack of medical degree among them, but the effect is not.
Cures, innoculation against disease, programs to combat everything from disease spreading mosquitoes to parasitic worms, wells, dams, and canal building, schools, and various infrastrucure, handing out lost cost gadgets (70% of all people on Planet Earth own a cell phone) oh, and them free bags of wheat and corn courtesy of Good Ol' Uncle Sam, has caused and maintained an ever increasing world population of 7,000,000,000 and counting.
You're welcome.