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Flu research could bring better vaccine for old and young

Flu research could bring better vaccine for old and young
"Anyone who has had a full-blown case [of the flu] can tell you how terrible it is," said Andrew Pekosz, an associate professor in the molecular microbiology and immunology department at Hopkins’ Bloomberg School of Public Health. (Kim Hairston / Baltimore Sun)

Every year, thousands of seniors across the U.S. die of flu complications. But Johns Hopkins University researchers say they are developing a way to boost the power of the seasonal influenza vaccine for elderly patients.

"This is a very vulnerable population, and this may be a better way to protect them," said Andrew Pekosz, an associate professor in the molecular microbiology and immunology department at Hopkins' Bloomberg School of Public Health and the lead researcher on the project.

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Pekosz's work involves retooling the existing FluMist vaccine and is still in early stages. In addition, other studies underway nationwide may improve production and eventually lead to a so-called universal vaccine that wouldn't change from season to season. Pekosz and others say progress in the next few seasons should not only help seniors, but make the flu vaccine more consistently effective for everyone.

"Anyone who has had a full-blown case can tell you how terrible it is," said Pekosz, whose study was published recently in the journal Vaccine.

Pekosz's vaccine would increase its power without increasing side effects. For that, he's altering the FluMist "backbone," the part that doesn't change with the season. He hopes to begin testing the vaccine in people within the year.

FluMist is made by AstraZeneca's research and development arm, Gaithersburg-based MedImmune, and is considered more effective than the standard injectable vaccine because it's still made from live flu virus, though weakened. It's not approved for seniors, who don't respond properly to it, and for children under 2 for safety reasons. Pekosz believes his method may benefit both groups.

He's been adjusting nine mutations in the weakened virus that he's been growing in human nasal tract cells in his lab, and making the virus stronger or weaker to produce the appropriate immune response in all people — analogous to a "dimmer switch."

Pekosz couldn't say when there would be new vaccines on the market, but regulatory approvals would be simpler because FluMist is already federally approved. Officials at the National Institutes of Health who fund research are optimistic about this and other incremental improvements to the vaccine and process.

For example, some researchers are working on growing the vaccine in cell cultures rather than eggs, a technical change that could produce more consistent vaccine batches that aren't dependent on herding so many healthy chickens.

However, the biggest advances aren't focused on the production, but on making the vaccine work better. The flu vaccine is less effective than vaccines for other diseases.

At NIH, that means developing a universal vaccine. The vaccine must currently be matched months ahead of the flu season to circulating strains, which is something of a "guessing game," said Dr. Anthony S. Fauci, director of NIH's National Institute of Allergy and Infectious Diseases.

"Most of the time we guess correctly," he said. "But not always."

Last year, the most common strain, known as H3N2, "drifted" — it changed over time. The shift caused a mismatched vaccine and an earlier and harsher flu season. Fauci couldn't yet say if officials this year got it right for the flu season, which typically runs from fall to early spring and infects up to 20 percent of the population with respiratory illness.

Typically, three strains are included in the vaccine, but a universal vaccine would eliminate the need to choose. It would incorporate four larger subtypes of an influenza virus protein called hemagglutinin. Two of them, H1 and H3, are known to cause seasonal flu in people, and two more, H5 and H7, are found in avian flu viruses that can also infect people, NIH has said.

Fauci said such a vaccine wouldn't be available soon, but there are likely to be incremental steps boosting coverage and strength, like Pekosz's vaccine.

"We need more powerful vaccines that protect more people, particularly older people," Fauci said. "We're not getting a universal vaccine in the next year or two. … But I expect advances."

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Patty Bayne of Pigtown said she'll take whatever protection she can get. A few years ago, the 63-year-old was diagnosed with chronic obstructive pulmonary disease, a lung disease that causes difficulty breathing and makes it especially dangerous for her to get the flu.

She began getting flu shots and even helped persuade her 80-year-old mother, Lena Campbell, to get vaccinated last year for the first time in her life. Campbell said she's always been healthy and "never considered" it.

But Bayne said, "I've known people who have had the flu, even young people, and it's knocked them out of commission for a week. I had my first grandchild about the same time as I was diagnosed with COPD, and I decided I wanted to be around."

She welcomed the possibility of a vaccine that was even better. So did Dr. Norman H. Edelman, senior scientific adviser for the American Lung Association, which has been pushing older people to be vaccinated against the flu during National Immunization Awareness Month in August.

Edelman called the flu a "very serious infectious disease" that can lead to deadly complications such as pneumonia.

He said even vulnerable seniors can be lax about getting the vaccine, and some refuse because they still falsely believe the vaccine causes flu, isn't likely to be effective or has a high probability of causing dangerous side effects.

"People absolutely don't take the flu seriously enough," said Edelman, also a professor of preventive and internal medicine at the State University of New York at Stony Brook. "Vaccination rates are not nearly as high as we would like. It's very frustrating."

For now, seniors' best bet is to get a double dose of the annual vaccine, or get a shot containing an additive to make it stronger , as well as a one-time pneumonia shot.

Eventually, new flu vaccines that work better could encourage more people to get vaccinated.

"There is a lot of exciting stuff going on in vaccine research," Edelman said. "In general, prevention of disease is far more effective than treatment. We ought to be spending more money in finding novel ways to prevent disease, instead of spending $3 trillion to treat it."

Treating the flu often falls to Dr. Tyler Cymet, an emergency room doctor and president of MedChi, the state medical society, which also has been encouraging older people to be vaccinated.

The U.S. Centers for Disease Control and Prevention recommends that anyone over 6 months old get a flu vaccination. Agency officials last year published a study that found the flu vaccine prevented tens of thousands of hospitalizations nationwide in seniors even during seasons when the vaccine effectiveness was low.

However, seniors do only a bit better in getting their flu vaccine than Americans in general, the CDC reports. Fewer than half of all people typically get a flu vaccine and an average of 30,000 die each year of complications from the flu, researchers estimate.

In Maryland last flu season, hospital emergency departments reported that 36,178 people came in with influenza-like illnesses, and doctors volunteering data said they had 6,123 visits from patients with flu symptoms. Most people are not tested for the flu, and health officials believe many sick people do not seek medical attention.

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Cymet said by the time he sees people with flu-like symptoms, they often have trouble eating or functioning.

"Once people see how sick they can get, they are much more likely to get vaccinated," he said.

Instead of treating flu patients, he'd like to save the emergency space for disease complications and injuries that aren't easily prevented. "That would be nice," he said.

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