@joemphelps when bugs get beach head like the zika carrier they do not go away and are not eradicated, they mutate as part of our ecology, the primary mosquito carrier species will cross to other species even as the virus will change and adapt. Some humans might become immune or resistant with in or after a generation. This the natural history of disease no one is talking about. Note no one talks about HIV/AIDS or Polio any more because it's being better managed but it's still here but not killing as many as it did years ago.