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Since April, when the H1N1 flu made its first appearance in Mexico and quickly spread to a worldwide pandemic, health officials in the U.S. have been promising to make a vaccine available as soon as possible.

Now it's here, and there's a new challenge: getting people to take it.

A recent poll by Consumer Reports found that two-thirds of parents plan to delay or skip getting their children the H1N1 shot altogether.

Some believe the vaccine was rushed and not adequately tested. Others just don’t trust flu shots in general and avoid them each winter like the plague.

But government officials say those concerns are irrational. H1N1 flu has hit children particularly hard — 36 youths in the U.S. had died from it through August — so they are advising parents very strongly to do what's best for their kids and get them vaccinated.

“I think many of the concerns by parents are based on the perception that this vaccine has been rushed into production and may not be safe,” said Tom Skinner, spokesman for the U.S. Centers for Disease Control and Prevention.

“And we understand parents' concerns — they want what is best for their children. We often tell people the best antidote for fear is information. And we ask them to really seek out sound and reliable information from sources they trust.”

Skinner said the vaccine was made in exactly the same manner as the seasonal flu vaccine, which has a “very, very good track record as far as safety is concerned.”

Health and Human Services Secretary Kathleen Sebelius made the rounds Tuesday and Wednesday morning, appealing to all Americans to get the vaccine and trust that it is safe.

Sebelius unconditionally vouched for the safety of the vaccine, saying it “has been made exactly the same way the seasonal vaccine has been made, year in and year out.”

Health experts say most fears about the flu vaccine, especially the seasonal vaccine, are unfounded.

The flu shot does not give people the flu. Side effects are generally mild — soreness and swelling at the injection site, headache, occasional fever and body aches (the mark of a healthy immune system responding to something foreign entering the body). Less common side effects include coughing, runny nose and nausea, especially in young children.

The incidence of more severe side effects is extremely low. Guillain-Barré syndrome — an autoimmune disease that attacks the peripheral nervous system and can be fatal — occurs in 10-20 people per 1 million adults, regardless of whether they’ve received a vaccine or not.

According to CDC tracking, there is correlation, although the cause is unproven, of one additional case of Guillain-Barré per 1 million people who have received the flu shot. Health officials say people have a better chance of getting struck by lightning — 1 in 700,000 chance — than they do of getting Guillain-Barré from a flu shot.

Fears about Guillain-Barré and the flu shot stem from a 1976 incident in which there were 500 cases and 25 deaths stemming from a bad batch of swine flu vaccine.

Sebelius this week assured that it will not happen this time around.

Appearing on morning news shows to step up the Obama administration’s campaign for vaccinations, Sebelius said that “the adverse effects are minimal. ... We know it’s safe and secure. ... This is definitely is a safe vaccine for people to get.”

Dr. Peter Welch, an infectious disease specialist at Northern Westchester Hospital in Mount Kisco, N.Y., said it is imperative that people trust the H1N1 shot, as it is the best protection against a virus that has already killed hundreds in the U.S.

“People need to get these vaccines because these illnesses are so much more severe than any side effects they will experience,” he said.

Because the flu is easily transmitted, especially in school and day care settings, Sebelius said, “We strongly urge parents to take precautionary steps. Flu kills every year ... and we’ve got a great vaccine to deal with it.”

Skinner said 1,300 people have died from the flu since the beginning of September, and most of those deaths have been linked to the H1N1 strain of the virus.

“I think what concerns us most is that more children may die this year because they weren’t vaccinated,” Skinner added. “And that would be tragic and we don’t want that to happen.

"We really implore any parent to seek out information that’s reliable and can help them make a decision that’s best for their child.”

The Associated Press contributed to this story.