Sep 19, 2007 (CIDRAP News) – Predicting that this year's supply of influenza vaccine will be the largest ever, national health officials today called on healthcare professionals and the public to improve the "alarmingly low" vaccination rates of recent years.
The Centers for Disease Control and Prevention (CDC) said up to 132 million doses of flu vaccine are expected to be available this year. Last year about 121 million doses were produced, of which 102.5 million were distributed, leaving at least 18 million unused, CDC officials said.
"We expect to have the largest supply we've ever seen," CDC Director Dr. Julie Gerberding said at a news conference today from the National Press Club in Washington. She said the production and distribution delays that hurt vaccination coverage last year are not expected this year.
CDC officials complained of persistently low vaccination coverage rates in many groups who should be immunized. In 2005-06, for example, only 18% of children aged 6 to 23 months received shots, and the immunization rate for healthcare workers has been stuck at about 40% for the last 10 years.
FluMist approved for small children
The call for broader flu immunization came as the Food and Drug Administration (FDA) approved the nasal-spray flu vaccine FluMist for children aged 2 to 5 years, except those who have asthma or wheezing. Until now, FluMist has been licensed only for healthy people between the ages of 5 and 49.
Three clinical trials involving a total of 6,400 children showed the effectiveness of FluMist, made by MedImmune, the FDA said. But the vaccine was not approved for children younger than 2 years, because the trials indicated an increased risk of hospitalization and wheezing for that age-group, the agency said.
At today's news conference, Gerberding said, "Year after year we come together knowing that we have not achieved the vaccination coverage rates that we need. . . . We're still failing to protect a large proportion of people, not just our seniors, who are at highest risk, but people of every age" who have a high risk of serious flu complications.
The CDC specifically recommends flu immunization for children from 6 months to 5 years of age; people with chronic medical conditions such as asthma, diabetes, heart disease, and HIV; pregnant women; people age 50 and older; healthcare professionals; and anyone who has close contact with high-risk groups.
Surveys show low coverage
Jeanne Santoli, MD, MPH, of the CDC reported some flu immunization survey data for the 2005-06 flu season. She said only about a third of children aged 6 to 23 months received at least one dose, and only about two thirds of those were fully immunized (two doses). "So only about a fifth of them were protected fully against flu," she said.
Santoli, deputy director of the CDC's Immunization Services Division, said 69% of people over 65 reported getting a shot, adding, "That's a high level, but it's far below our national goal, which is 90%."
She said 37% of 50- to 64-year-olds and 31% of high-risk people between ages 18 and 49 received shots. And the coverage among healthcare workers has remained at about 40% for the last 10 years, she added.
"It's unconscionable that a healthcare worker would not receive this vaccine," commented Gerberding.
During the question-and-answer part of the conference, a man who identified himself as a Service Employees International Union member said more education is needed to promote flu immunizations among healthcare workers.
"The biggest issue for our members is the education piece, and we don't really see it happening in a lot of places," he said. "There's a lot of fear about this among our members."
He added that many healthcare workers were fearful of the hepatitis B vaccine, but education efforts helped to boost the vaccination rate above 70%.
Helathcare workers have influence
Ardis Hoven, MD, a Kentucky infectious-disease specialist and board member of the American Medical Association (AMA), said healthcare workers should use their influence to persuade patients to get flu shots.
"Studies show that a healthcare worker's recommendation is one of the strongest factors influencing a person to get vaccinated," she said. The AMA and other medical societies "urge healthcare personnel to use every interaction to talk to people about flu vaccine," she added.
As in past years, officials spoke of the goal of stretching the flu vaccination season well beyond its traditional end at Thanksgiving in order to get the vaccine into more people. On average, US flu activity peaks in February.
Santoli said the CDC is designating the week after Thanksgiving—Nov 26 to Dec 2—as "National Vaccination Week." "We must use opportunities in December, January, and beyond in order to protect more Americans against flu," she said.
"The message to providers is, don't go cold turkey and stop vaccinating" after Thanksgiving, said William Schaffner, MD, of Vanderbilt University, vice president of the National Foundation for Infectious Diseases. "The message to patients is, give thanks that you can still get the vaccine in December and January."
Staying home isn't enough
Schaffner said some people think staying home from work when sick with the flu is sufficient for protecting others from the virus. He warned against that assumption: "The day before you become sick, when you're still feeling robust, you're already excreting the virus. So you're inoculating your family and your colleagues at work."
Gerberding noted that the flu vaccine works better some years than others, depending on how well the strains used in the vaccine match circulating strains. "But even when it's not a perfect match, we still see protection."
One strain that is now circulating in the southern hemisphere but is not in the northern hemisphere vaccines is an H3N2 strain called the Brisbane-like lineage, she said.
"It's very unpredictable as to whether that's important or not important," Gerberding said. "Picking the future strains is an art, not a science. The one thing we don't have in our Strategic National Stockpile is a crystal ball." But in 15 of the last 18 years, all three strains in the vaccine have been excellent matches with circulating strains, she added.
Shots free for Medicare patients
Also at the press conference, Kerry Weems, acting administrator of the US Center for Medicare and Medicaid Services, stressed that both flu and pneumococcal pneumonia shots are free for Medicare recipients.
"In this case, free should be cheap enough," Weems said. Yet, "In any given state, at least 20% of people with Medicare aren't getting the flu shot."
Pneumococcal pneumonia is the most common bacterial pneumonia, Weems noted. People over age 65 need to get the pneumococcal shot only once, and they can do it when they get their flu shot, he added.
Those who have flu have a much higher risk of contracting pneumococcal pneumonia, said Dr. Robert Hopkins Jr, MD, of the University of Arkansas for Medical Sciences. "When deaths due to flu and pneumonia are combined, it's the eighth leading cause of death in this country," he said.
Antiviral drugs continue to play an important role in treating and preventing flu, the CDC said. For this season, the agency recommends use of oseltamivir (Tamiflu) and zanamivir (Relenza), the newest of four available flu antivirals. The two older flu drugs, amantadine and rimantadine, are not recommended because of high levels of resistance. The CDC first made this recommendation in January 2006, after finding that more than 90% of H3N2 isolates were resistant to the two older drugs.
CDC recommendations on flu prevention and control for 2007-08
Sep 19 FDA news release about FluMist for small children