LOS ANGELES, CA (Catholic Online) - Last year was the mildest flu season on record - but that's no reason to become complacent, officials say. 

Last year's flu shot won't shield you this year. There are two new strains of influenza that have begun circling the world. The current vaccine appears to work well against them, government officials say.

"People cannot become complacent this year," Dr. Howard Koh, assistant secretary of the Department of Health and Human Services says.

Doctors say that the only people who shouldn't get vaccinated are babies younger than six months and people with severe allergies to eggs, which are used to make the vaccine.

Strains from the H3N2 family tend to be harsher than some other flu types, and a new H3N2 strain is included in this year's vaccine because it is circulating in parts of the world.

Flu specialist Dr. Daniel Jernigan, with the Centers for Disease Control and Prevention, explained that because of that strain, the coming flu season will probably be a more traditional flu season than last year. "People won't have had any real exposure to that," he said.

One ingredient in this year's flu vaccine has been retained from last year's, protection against the H1N1 strain that caused the 2009 swine flu pandemic and has been the main kind of influenza circulating since.

Also in this year's shot is protection against a different Type B strain.

An annual vaccination is recommended for nearly everybody, but new figures released show that last year 52 percent of children and just 39 percent of adults were immunized.

Three-quarters of tots ages 6 to 23 months were vaccinated turned out to be the best protected. That's a significant jump from the previous year, when 68 percent of those youngsters were immunized.

While seniors are at especially high risk of severe illness or death if they catch the flu, just 66 percent of them were immunized, a number that has been slowly dropping for several years.

Older adults got a little lost in the recent public health push to explain that flu vaccine benefits all ages. Child deaths from flu have made headlines in recent years. The U.S. counted 34 pediatric deaths in 2011, which has raised parents' awareness of the risk.

© 2012, Distributed by NEWS CONSORTIUM.