A 1 micron droplet released from 5 feet stays airborne for 12 hours. Is that airborne enough for you?
That is the kind of droplet nucleus used by viruses like chicken pox and measles, and maybe influenza, to spread. As I have explained many times, you do not need to be near an infected person, either in distance or in time, to catch an airborne disease.
The kind of particle that can stay airborne is small enough that it dries almost instantaneously. Ebola is fragile and cannot tolerate being dried out; it is also susceptible to a number of environmental factors. It is also large enough (it is several times the size of airborne viruses) that an infectious dose is highly unlikely to be contained within a particle. One micrometer = 1000 nanometers; an Ebola virus is 80 nanometers in diameter and anywhere from 970 to 14,000 nanometers in length. Clearly, there is a size incompatibility there.
Droplets are large enough to fall to the ground before they dry out. Droplet nuclei are particles that dry out before they hit the ground, which allows them to remain airborne. Some airborne viruses can travel for long distances and remain infectious. For example, a veterinarian friend told me that the virus that causes hoof and mouth disease can travel for miles, which is why every susceptible animal in entire counties is culled if a single case of hoof and mouth is found.