Will Man be the Creator of a Zombie Apocalypse?

When a Zombie Apocalypse occurs, why will it happen? What will be the cause of this threat to humanity?

The human race itself will be responsible for the "rise of the dead" not literally of course, but with some form of disease or virus. Some sort of mind or body altering substance. The zombie movies all show some kind of contaminating exposure to humans which is behind zombie creation and transformation of normal people, into these monsters.

It may not be intentionally done, but sometimes the unexpected is unbelievable. A conflict between countries may allow a test of chemical weapons to be used on a large population of the enemy. The results may be unknown for certain lengths of time. This can easily be something that will spark a population of infected humans. They may be seen as zombies if they are carrying contagious viruses and appear to act "undead" or violently attacking others in wild ways.

Another possibility is that a virus or disease can just evolve out of nature and begin its course onto mankind, a sickness that can transform the mind in such a way that someone may become violent and "hungry" for other humans or live animals.

Cannibals have been recognised in the past as having psychological and mental instability. Most people seem to think these are reasons we can expect a zombie apocalypse to happen. Nobody knows for sure, do they?...

Center for Disease Control Mentions Zombie Apocalypse Regarding Recent Zombie Attacks

The CDC, Center for disease control in the U.S. has come out and announced that there is no such zombie virus or disease spreading around. All of the recent zombie like and cannibal attack incidents are cause of something else on an individual case by case basis.

Some say it's spiritual and evil or the devil is among us, some say it's drug related and the incidents happened as a result of narcotics or the popular rumor of  "bath salts", and some have just called them psychotic episodes of crazy or mentally ill individuals who have gone mad.

We shouldn't be alarmed since a zombie apocalypse is not likely.
Can someone give an explanation of all the recent incidents of people eating each other? If something were going on, and it was a small situation, it would be kept top secret by the government and health officials to prevent a nation wide panic situation from occurring.

For now, maybe we'll just keep a close eye on future events and see how they compare to the past craziness we've witnessed.