The race to get the H1N1 vaccine out, has hit a major hurdle.

The problem, drug makers can't churn it out fast enough. The federal government is urging states to brace for a three week delay for more of the vaccine. Michigan expected to have several million doses by now. But at this point, health providers have only about 400,000.

Dr. Dean Sienko, Ingham County Medical Director: "We're weeks behind where we anticipated being."

It's an unpredictable virus keeping drug makers busy and health officials guessing.

Dr. Dean Sienko, Ingham County Medical Director: "The vaccine supply picture changes almost daily."

Just as health officials gear up to protect the population, they say the H1N1 flu is now widespread across the state.

Dr. Eden Wells, Michigan Department of Community Health: "We are going to have more sick people and potentially more problems with deaths, hospitalizations, and what we're really worried about right now, children."

Doctor Eden Wells is the state's swine flu expert. She says the virus thrives among children and their environments. Health officials are scrambling to protect as many as possible. But without enough vaccine, it may be slow going.

Dr. Dean Sienko, Ingham County Medical Director: "It puts us in a very difficult position. We want to vaccinate as we can as quickly as we can, but if the supply is going to be limited, we will vaccinate those who are most at risk."

Dr. Eden Wells, Michigan Department of Community Health: "I don't think there should be panic. I don't think there should be intense worry. I think there should be awareness."

Health officials say, until more vaccine arrives, the best way you can protect yourself, is to practice good hygiene, and stay home if you're sick.

Dr. Dean Sienko, Ingham County Medical Director: "Certainly anyone who has a fever, greater than 100 degrees. We would be very concerned that that would be H1N1."

A virus on the move, closing schools, packing emergency rooms, and keeping health officials focused on the weapon they need to fight it.

Health officials say the vaccine delay may force them to postpone some school immunizations, but they'll wait until next week to make those decisions.

Right now, they're focusing on high risk groups: pregnant women, caregivers of children 6 months and younger, children aged 6 months through 4 years old, and children with medical conditions.