My understanding is that the disease was already wiping out entire families before authorities recognized what was going on and sent in the space aliens. Patie

My understanding is that the disease was already wiping out entire families before authorities recognized what was going on and sent in the space aliens. Patient Zero for this outbreak is thought to have died in December of 2013. Local authorities didn't recognize an outbreak of something until mid-March, and it was't until late March that WHO started sending people in. By that time there were already 70 dead. So it is more like "Year after year, you have some people get sick, some die, some live. One day somebody gets sick and dies fast and painfully. A few weeks later the rest of their tribe/family is dead or dying. A few weeks after that, the space aliens start coming in, but people continue to die."