International health
Governments of rich, "developed" countries are often interested in the health of other countries. They are especially interested in the health of neighbor countries. The reasons for this are many: if they have extra resources, they may want to share them with their neighbors; but also they may want to stop spread of diseases from their neighbor country across the border. For example, the United States is a richer country than Mexico and has little problem with measles (in children) or rabies (in mammals) in the interior, but along the border with Mexico these diseases are more common.