They try out this gene, they try out that gene, pretty soon they've gotten around the block. One and a half million die from tuberculosis. The realities of the modern world are partly to blame. The world is getting smaller, tighter, more interconnected. People and products are on the move, as never before.
Air travel means a disease can be halfway around the world, in a matter of hours.
There's no barrier that you can put up against a virus. It can just move continuously across countries and across areas. And the answer to that is yes. Anyone who's traveled to the Indian subcontinent or Africa knows that one of the things to be careful about is malaria. As we mentioned, about a million people a year who get it die.