ATLANTA — When the nation's swine flu vaccination program began in early October, health officials predicted it was going to be "messy." They were right.

The program has been plagued with problems and information gaps:

• Health officials have been terrible at predicting when and how much vaccine would be available. Only about 44 million doses have been shipped so far. Initially, officials said more than three times that would be out by now.

• At times, vaccine shipments have been inexplicably lopsided. For example, smaller counties in Illinois and California have received the same amount delivered to counties with seven times as many people.

• Health officials have stressed that people most at risk for swine flu complications should go to the head of the line, but they haven't tried to make sure that is actually happening.

• Despite pledges that they would be transparent about the vaccine program, some health officials have refused to disclose where all the doses are going, and they have held back on public service announcements telling people who should be coming in for shots. Also, many states were slow to establish Web sites that give vaccination locations.

To be fair, health officials say, the government deserves credit for a herculean effort to develop and distribute a safe and effective vaccine against a deadly virus that was first identified only seven months ago.

"You have a brand-new disease that gets identified in April. By October, you have a vaccine for it. By any standards, it's a miracle," said Dr. Diane Helentjaris, director of the Virginia Department of Health office that is handling swine flu response.

But complaints have been mounting, with lawmakers this week holding hearings in Washington and elsewhere, pressing for explanations.

People are frustrated everywhere, said Sen. Susan Collins, R-Maine. At a hearing in Washington on Tuesday, she complained of "layers of misinformation and miscommunication."

Arthur Caplan, director of the University of Pennsylvania's Center for Bioethics, said health officials should have done more to make sure limited doses get to the people most at danger from the virus. And he said they should have been tougher on nurses and other health care workers who are putting their patients at risk because they declined to get a shot.

"It is not working right at all," Caplan said.

In their defense, officials at the U.S. Centers for Disease Control and Prevention have said that the main issue is insufficient vaccine from manufacturers – something the CDC can't control – and that health authorities are doing the best they can.

"A lot of this is a function of not having as much vaccine as we would like to have," said Dr. Anne Schuchat, who heads the agency's immunization section.

The new swine flu, also called 2009 H1N1, has not turned out to be the deadly global disaster that experts have long feared. But it has sickened an estimated 22 million Americans, hospitalized about 98,000 and killed 4,000. It has proved to be similar to seasonal flu, but a much bigger threat to children and young adults.

There was no vaccine to protect against the new virus, so manufacturers had to create a new one. In July, a government health official estimated 120 million vaccine doses would be available by late October. Later, the government backed away from that estimate when manufacturers couldn't crank out vaccine so rapidly.

The CDC has been coordinating the vaccine campaign, but it is not fully in charge. As a matter of tradition and law, states have had more public health authority than the federal government. Each state health department has made decisions about which clinics, doctor's offices and other sites get vaccine from a federally contracted distributor.

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