The bird flu virus can be compared to a monkey with a typewriter. And that's why it's getting more and more dangerous.

You may have heard the old observation that if you give enough monkeys a keyboard, eventually one will -- just by random chance -- type out the complete works of Shakespeare.

Of course, the odds against one monkey doing this are extremely high. The universe might implode before one monkey could do this.

But give a trillion monkeys a keyboard and maybe one will do it in a few million years. Give as many trillion monkeys as it takes to stretch from here to the next galaxy a keyboard, and chances are one out of those gazillions of monkey will actually type out the complete works of Shakespeare.

I'm comparing monkeys to the bird flu virus or A/H5N1.

The bird flu virus doesn't have to do anything comparable to a monkey typing out Shakespeare. It just has to mutate or recombine genetic material to become high contagious to people. That's the start of a pandemic.

For viruses, that's a lot easier to do than for a monkey to type out the complete works of Shakespeare. There're many strains of influenza viruses in the world which are highly contagious to people. Most of us have suffered from the flu, caught from a child or coworker, so we know that.

The more A/H5N1 viruses there are this world, the higher the probability that one of them will become highly contagious, human to human, just as ordinary flu is now.

Just as with monkeys -- the more viruses, the faster one of them becomes highly contagious.

Yes, A/H5N1 "hid out" in chickens in China and wild ducks from the December 1997 massacre of chickens in Hong Kong until bird flu started killing chickens in South Korea.

It spread through most countries of Southeast Asia without becoming a pandemic. It's spread into Europe and Africa without becoming a pandemic -- so far.

The more people or animals bird flu infects, the more H5N1 viruses there are. Replicating, mutating and recombining with ordinary flu viruses.

Whether it's chickens in Thailand, cats in Germany or little girls in Turkey . . . the more viruses, the greater the probability it will become highly contagious.

And because it's now so widespread, there's little chance that it will be contained soon. Scientists expect it to land in the New World by autumn.

It's out of control and spreading fast.

How long before one out of those many countless trillions of viruses becomes highly contagious?