Federal health officials are urging that more Americans than ever before get flu shots, including, for the first time, children age 6 months through 18 years.
Experts say they are also concerned about adults over 50. While two-thirds of those over age 65 were vaccinated against the flu last year, only 36 percent of those between 50 and 64 were immunized. Experts urged health care providers to get their patients vaccinated.
"The message is not getting out to those in the 50-plus category," said Dr. Cora L. Christian, a member of the AARP board of directors, who spoke yesterday on a panel sponsored by the National Foundation for Infectious Diseases. "Many myths exist about influenza vaccination, but the evidence is clear - vaccines, regardless of age, offer the best method to prevent disease."
Local health authorities say they are ready, and most public vaccination clinics will launch their fall schedules in October, with some beginning Oct. 1.
"We're flush with vaccine. We got our supplies the earliest ever," said Dr. Anne Bailowitz, chief of the Baltimore City Bureau of Child Health and Immunization.
The recommendation for flu vaccinations for all children ages 6 months through 18 years - except those with a serious egg allergy - adds roughly 30 million children to the list of those who should be vaccinated. Last year, the recommendation was for all children ages 6 months to 5 years.
School-age children have the highest rate of flu infection. Nevertheless, last year only 21 percent of children were vaccinated against the disease, said Julie L. Gerberding, director of the Centers for Disease Control and Prevention.
Getting vaccinated early is important for children ages 9 and younger, who need two doses of the vaccine if they are receiving it for the first time, said Daniel B. Jernigan, deputy director of the CDC's influenza division.
"The time to get vaccinated is now," he said.
Officials also urged shots for pregnant women, people with chronic illnesses, people 50 and older, health care workers and caregivers. All together, the CDC is recommending vaccines for about 261 million people, or nearly 85 percent of Americans.
Complications from seasonal influenza kill an average 36,000 Americans each year and send 200,000 to the hospital. The season typically lasts from December through March, peaking in January and February. But it's not too early to be immunized, officials said. A vaccination in October will provide immunity within two to three weeks and last throughout the flu season.
The CDC said manufacturers have produced more than 143 million doses of vaccine this year, more than ever before. But many more Americans will have to roll up their sleeves to use up that much.
"Never in the history of America have we given out anywhere near that," said Dr. Peter L. Beilenson, the health officer for Howard County, where public flu clinics begin next month.
Part of the push to get more people vaccinated is simply to keep more people healthy, he said. For example, "There has been some evidence that for seniors it may not have been as effective as originally thought. However, there is nothing better to prevent the flu. It is still better than nothing."
And for younger people it's clearly important, both to protect their health and to prevent them from becoming "vectors," spreading the virus to more vulnerable groups, including the elderly and those with compromised immune systems, Beilenson said.
Another reason to push for more vaccinations, he said, is "to keep the vaccine companies making these large numbers. If year after year you waste 10 million doses, it's harder to get them to do that."
Last year, Americans used only 113 million of the 140 million doses of flu vaccine that were manufactured, according to the CDC.
This year, the CDC's goal is to have 90 percent of people over age 65 vaccinated. Only a third of young adults with chronic illnesses, such as asthma, heart disease or a weakened immune system, were vaccinated as recommended in the 2006-2007 season. Only half of those ages 50 to 64 with those conditions were immunized.
Once again this year, Americans have two types of vaccine available - the familiar shots and a nasal spray. Both are protective against the three influenza strains that experts determined we are most likely to confront this season.
The injections are made from killed viruses, so they are incapable of transmitting the disease, although soreness, minor aches and a low fever are possible side effects, according to the CDC. The shots are recommended for people older than 6 months, whether they are healthy or immune-compromised.
The second vaccine is the nasal-spray, called FluMist. It's made from a live, weakened virus, that can produce mild symptoms. It is approved for healthy people ages 2 to 49 who are not pregnant.
Bailowitz, of the Baltimore health department, said it's important to maximize the percentage of people who are immunized because of the influenza virus' uncanny ability to mutate and dodge the defenses of the human immune system.
"With the flu, it's a moving target," she said. The viral genes shift, and annual flu vaccines provide only partial and temporary immunity. Immunity across the population is harder to establish without more widespread vaccination. "A 20- to 30-percent vaccination rate doesn't cut it."
Public health officials say they're also fighting a common and persistent myth about flu vaccines - the often repeated complaint that "I got the shot and it made me sick," or "I got the flu anyway."
The first complaint is "clearly a fallacy," Bailowitz said. "The shot in the arm is killed virus. There are no live 'bugs.' ... That is an unfortunate myth we have every year to combat."
The second myth is likely perpetuated by the fact that the flu vaccine does not protect against other respiratory diseases that circulate in the winter, and that the vaccine is not 100 percent effective, said Dr. Robert Edelman, associate director of clinical research at the Center for Vaccine Development at the University of Maryland School of Medicine.
Critical to protecting the most vulnerable populations from the seasonal flu, Edelman said, is immunizing as many young children as possible.
"The kids bring it home first," Edelman said. Their immune systems are "naive," so they more easily catch the flu, and they get sicker. "They have a lot of virus. They're sneezing, they cough in their hands and then they come and kiss Grandpa ... or share a cup of root beer with Grandma."
The elderly tend to be partially immune, thanks to their long years of exposure to similar flu strains, and they put out less virus than kids.
"Nevertheless, they can get quite sick from it," Edelman said, especially those with chronic heart or lung conditions, cancer, or those taking drugs to suppress the immune system, including steroids used to control asthma.
To find a flu immunization clinic near you, visit www.findaflushot.com