I found your post to be a relief, but I wish it would just burn out already.
Truthfully, biologically speaking many pathogens are natural controls on animal, and human, populations. While people have had some success in holding epidemics back for the last about 70 years, it has just insured that when they do punch through our defenses, a lot more people are going to die.
By far, the worst threat is Influenza, and by all appearances H5N1 showed (and still shows) prospects for becoming the most lethal epidemic in human history. And why it has not accomplished easy human to human transmission is a great mystery.
Ebola could naturally only produce a very limited epidemic, outside of 3rd and 4th world nations, because modern nations have the infrastructure to halt it in its tracks. A combination of quarantine, personal and clinical hygiene and sanitation, and a population that generally understands infectious diseases, make it extremely hard for a gigantic epidemic here.