Children ages 2 to 5 should get flu shots, an advisory panel said Wednesday, widening the group of Americans urged to seek protection from a virus that kills thousands in this country each year.

The recommendation, which covers 5.3 million healthy U.S. children, was unanimously approved by the Advisory Committee on Immunization Practices. The panel's advice is routinely adopted by the federal Centers for Disease Control and Prevention, which issues vaccination guidelines to doctors and hospitals.

Flu shots are already recommended for children ages 6 months to 23 months, pregnant women, people 65 and older, and people of all ages with chronic health conditions, along with a few other groups.

The new recommendation was cheered by Alissa Kanowitz of New York City, the mother of a 4-year-old girl who died from the flu in 2004.

"It's too late for us to do anything for Amanda now. But hopefully this will help other children," said Kanowitz, 37, member of a group called Families Fighting Flu who spoke to the committee before the vote.

The panel also considered encouraging all Americans to routinely get flu shots. However, committee members narrowly defeated the proposal, saying more study and planning are needed.

Research data shows the flu virus can put children with certain risky health conditions at grave risk of death or hospitalization. But scientists have debated how dangerous the flu is to healthy children older than 2, and how effectively vaccination prevents flu and flu-like illnesses in such children.

Typically the committee looks for evidence that such a measure would reduce deaths and hospitalizations. But in this case, they gave heavy consideration for reducing visits to doctor's offices and emergency rooms.

Wednesday's decision marks "a paradigm shift" in how the committee makes vaccination recommendations, in that the panel is focusing not only on how vaccination helps individuals, but also how it helps society by blocking the spread of infectious disease, said Dr. William Schaffner, a Vanderbilt University preventive medicine expert.

Immunizing children against hepatitis A and other infectious diseases has led to fewer illnesses in the children's parents and grandparents, he noted.

"The kids were giving the hepatitis A virus to mom, dad and Uncle Tom. And so if they didn't get the disease, the parents were protected," explained Schaffner, a board member for the National Foundation for Infectious Diseases.

The foundation gets money from a vaccine manufacturer, Sanofi Pasteur. Families Fighting Flu gets funding from another vaccine manufacturer, MedImmune Inc.

About 180 million Americans are in population groups currently recommended to receive flu vaccinations, and yet manufacturers are expecting to throw away some of the 100 million doses produced for this current flu season.

Health officials have been concerned about periodic shortages of flu vaccine, and are encouraging manufacturers to commit to substantial annual dose production. A recommendation to expand flu shots will reassure manufacturers, said CDC Director Dr. Julie Gerberding.

"Obviously, if there's an expanded recommendation for using the vaccine, the market increases," Gerberding said.

The committee's action allows a government program, Vaccines for Children, to pay for flu shots for kids ages 2 to 5. That could mean coverage for roughly 2 million more children in that age range who are uninsured, under-insured or meet other criteria.