Vaccination rates among the young and old are improving, but infectious disease experts still urge everyone over the age of six months to get a flu shot.

The U.S. has a higher supply of influenza vaccinations—135 million doses—than ever before, and usage rates are increasing. But experts continue to urge vaccinations for all who qualify.

While flu seasons are unpredictable, experts are attempting to prevent another flu season like last year’s. The 2012 flu season struck early and was one of the most intense ever recorded, lasting 15 weeks and causing 164 pediatric deaths, the highest in recorded history.

To prevent a further outbreak, experts recommend that people get vaccinated early, as it takes two weeks after vaccination to build up the antibodies needed to fight the flu.

Altering the Flu Virus’ Sense of Time Could Yield New Vaccines

“We know a lot about the flu. We know how unpredictable and deadly it can be. This was evident last year,” Dr. William Schaffner, immediate past-president of the National Foundation of Infectious Diseases told reporters Thursday morning. “Last year we had the earliest onset of the flu season in the last decade.”

As far as the best prediction for this year’s flu season, Schaffner said the flu season “will be here and it will cause illness.”

Nationally, there was a 5.1 percentage increase in child vaccinations and 2.7 percent increase in adults during last year’s flu season, according to the U.S. Centers for Disease Control.

Rhode Island leads the nation with 82 percent of all children becoming vaccinated. For adult vaccinations, South Dakota leads with 53 percent receiving a vaccination. Nationally, 51 percent of pregnant women were vaccinated last year.

While that gives experts optimism, they noted that the best way to ensure that pregnant women become immunized is for doctors to recommend and provide vaccines in their practices. When that occurs, up to 71 percent of expecting mothers get the vaccine. Only 16 percent become immunized if their doctor doesn’t recommend it or offer it.

Dr. Laura Riley, medical director of Labor and Delivery at Massachusetts General Hospital, said last year’s flu epidemic highlighted the dangers of expecting mothers not being vaccinated. Those dangers include premature birth weights and hospitalizations. While mothers are right about worry of the safety of vaccinations, data from the 2009 H1N1 virus proves they are safe.

“We really need pregnant women to get vaccinated,” Riley said.

Pregnant? Get a Flu Shot to Protect Your Baby

Expecting mothers, small children, seniors, and people with compromised immune systems are at the greatest risk of complications related to the flu. The CDC reports that while only 66 percent of adults over the age of 65 were immunized last year, that’s still the highest rate ever.

More vaccination options have made vaccination a new national standard, fully covered by law under the Affordable Care Act, according to Dr. Howard Koh, assistant secretary for health at the U.S. Department of Health and Human Services.

“Too many Americans are not receiving the protective services they need,” Koh, who received a flu vaccination at the press conference, said. “Overall, the best vaccine is the one that’s delivered.”

In addition to the standard vaccination, there is a high-dose version for people 65 years and older, one with a much smaller needle for adults 18 through 64 years old, an egg-free version for adults 18 through 49 years old, and a nasal spray.

“You don’t have to think about it anymore,” Schaffner said. “Vaccination is recommended to everyone—everyone—over the age of 6 months.”

Earlier this month, researchers at Imperial College London announced that they were closer to a universal flu vaccine. Professor Ajit Lalvani and other researchers from the National Heart and Lung Institute followed cellular activity from 342 staff and students at Imperial during the 2009 flu pandemic. Their research was published in the journal Nature Medicine.

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