Here's my non-shitty point. It must hurt them to not do something. They must suffer, and I choose that word specifically, consequences for NOT doing it. And not the moral consequence of causing harm to other people, but real, hard consequences. Like impeachment, or jail time, or a public flogging. I find that unlikely to happen because again, nobody making these decisions cares about poor people. As another example, the deaths of all of the workers constructing the Fifa stadiums in Qatar.but world leaders might.
I think there are two points here, both valid. 1) Rich people will be harmed in the long term as the Zika virus will end up hurting them by causing the society to overall be injured and less efficient in the long run, and while fewer rich people will be effected some will be. 2) Rich people are too shortsighted and self-absorbed to care, and won't care until the disease starts directly effecting them. By then it will be too late.