National emergency, words sure to get your attention.

We know vaccines are taking longer to distribute than first expected.

So what's the hold up?

Health and Human Services Secretary Kathleen Sebelius says vaccine for H1N1 is coming out the door as fast as it comes off the production line but she says it's unfortunate supplies are not where officials intended them to be at this juncture.

The Centers for Disease Control explain how the vaccine is created.

"This is a really frustrating situation. Influenza vaccines are produced through biological staffs, like baking bread. You're growing viruses in eggs and each egg is cracked and you try to see how much virus you've gotten. The manufacturers haven't gotten as much as they would have expected. We're really seeing a big delay," says Dr. Anne Schuchat, Centers for Disease Control and Prevention.

Senator Mitch McConnell said Sunday that Congress would be happy to provide additional support and money on a bipartisan basis, if the need arises.