typically in nature a population explosion event occurs when top-down forces, predation, go away for some reason, like parvovirus in wolves (or extirpation by humans) can result in moose, deer, or caribou population explosion. Invariably, bottom-up forces will then kick in like sickness and starvation. The whole ecosystem takes a big hit in indirect ways. Humans have staved this off to some degree by our technological abilities to feed and heal ourselves. At the expense of many other species of course. But make no mistake. Things are getting worse. We can run, but we can't hide from it. Cheers.