As we assemble this afternoon for the final session, permit me, ladies and gentlemen, to express our gratitude to the organizers of the Symposium—the Government of El Salvador, the Center for Disease Control, the Pan American Health Organization—for bringing together scientists, field workers, and administrators of various programs to discuss the many aspects of malaria research and the results obtained so far. I am sure everyone shares my view that the Symposium has been a real success and that we shall leave El Salvador feeling more optimistic about the future of malaria programs in this part of the world.

All of us were impressed with the results coming from certain areas of malaria research, especially the findings on immune phenomena. Already, developments in the field of malaria serology may make new techniques available to supplement surveillance and facilitate epidemiological evaluation. At the same time, the intensive research on immunization possibilities and procedures and the results obtained so far are making our hopes not too far from reality.