Flu shot much more effective this year, CDC says

by Steven Reinberg, Healthday Reporter

This year's flu shot is already outperforming the vaccine issued during the tough 2017-2018 influenza season, federal health officials reported Thursday.

18 feb 2019--The 2017-2018 flu shot offered just 25 percent effectiveness against the predominant strain of flu that season, H3N2. But this year's shot offers 47 percent protection against all circulating strains, according to researchers at the U.S. Centers for Disease Control and Prevention.

In other words, getting the current vaccinecould nearly cut in half your odds of acquiring a severe case of the flu.

The news was even better for vaccinated kids.

"For children aged 6 months to 17 years, overall vaccine effectiveness was 61 percent," the CDC team reported.

That's based on data up to Feb. 2 on nearly 3,300 children and adults enrolled in the U.S. Influenza Vaccine Effectiveness Network, said investigators led by Dr. Joshua Doyle of the CDC's Influenza Division.

Still, the latest agency statistics show that the United States remains in the grip of the flu and the season may not have peaked yet.

As of Feb. 2, flu is widespread in 47 states, and 24 states are experiencing high levels of the disease. In addition, hospitalizations are increasing, CDC research showed.

"Flu activity has continued to increase," Lynnette Brammer, the lead of CDC's domestic influenza surveillance team, said when the stats were released last Friday.

The most common type of flu around is still the influenza A strain H1N1. But it may be waning, Brammer said, as the level of influenza A H3N2 has increased.

Both of these flu strains are included in this year's vaccine.

The CDC stressed that everyone over 6 months of age should get the flu shot.

Even during last year's brutal season, when the flu shot had relatively low effectiveness, the vaccine saved many lives.

"Vaccination [during 2017-2018] was estimated to prevent 7.1 million illnesses, 3.7 million medical visits, 109,000 hospitalizations and 8,000 deaths," Doyle's team reported.

This flu season is expected to continue for several more weeks, probably well into March, Brammer noted.

"There's still a lot more flu season to come," she said. "I expect activity to continue for several more weeks."

That's why she's urging anyone who hasn't yet been vaccinated to get a flu shot. "It's not too late," Brammer said.

One underrated benefit of the vaccine is that even if you do get sick, your flu will likely be milder than if you haven't been vaccinated. A milder flu can prevent complications like pneumonia that can be deadly, especially to the very young and very old.

Brammer also stressed that getting vaccinated not only protects you, but those around you, as well.

According to the CDC, flu activity is high in New York City, Alabama, Alaska, Arkansas, Colorado, Connecticut, Georgia, Indiana, Kansas, Kentucky, Massachusetts, Mississippi, Nebraska, New Jersey, New Mexico, North Carolina, Oklahoma, Rhode Island, South Carolina, South Dakota, Texas, Utah, Vermont, Virginia and West Virginia.

It's still too early to tell how severe this season will be, Brammer said. So far, the season has been much less severe than last year when the H3N2 virus predominated. Last year, flu sent nearly 1 million Americans to the hospital and killed about 80,000.

This season is still classified as a less severe season, Brammer said. "But we're not finished yet," she said. "We'll have to see how it plays out."

The CDC doesn't track adult deaths from flu, but they do keep tabs on pediatric deaths. As of the latest data, a total to 28 children have died from flu.

If you get the flu, antiviral drugs such as Tamiflu and Relenza can make your illness less severe. But if you're sick, the CDC recommends that you stay home so you don't infect others.

The vaccine effectiveness study was published Feb. 15 in the CDC's Morbidity and Mortality Weekly Report.

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More information: Lynnette Brammer, M.P.H., lead, domestic influenza surveillance team, U.S. Centers for Disease Control and Prevention; Feb. 15, 2019, Morbidity and Mortality Weekly Report

For more about the flu, visit the U.S. Centers for Disease Control and Prevention.

Study makes major advance toward more effective, long-lasting flu vaccine

The team from The Scripps Research Institute and Janssen Pharmaceutical Companies designed a molecule that mimicked the shape of a key part of the influenza virus, inducing a powerful and broadly effective immune response in animal models. Credit: the Wilson lab, The Scripps Research Institute.

25 aug 2015--Scientists from The Scripps Research Institute (TSRI) and the Janssen Pharmaceutical Companies of Johnson & Johnson (Janssen) have found a way to induce antibodies to fight a wide range of influenza subtypes—work that could one day eliminate the need for repeated seasonal flu shots.
"This study shows that we're moving in the right direction for a universal flu vaccine," said Ian Wilson, Hansen Professor of Structural Biology and chair of the Department of Integrative Structural and Computational Biology at TSRI.
The study was part of TSRI's long-term collaboration to strengthen research against infectious disease with the former Crucell Vaccine Institute, now known as Janssen Prevention Center and headquartered in Leiden, the Netherlands.
The research was published online ahead of print on August 24 by the journal Science.
The Need for Better Flu Shots
Seasonal flu typically causes more than 200,000 hospitalizations and 36,000 deaths every year in the United States, according to the U.S. Centers for Disease Control and Prevention. While a yearly flu shot provides some protection, subtypes not covered by the vaccine can emerge rapidly. This phenomenon was evident in the 2009 spread of the H1N1 ("swine flu") subtype that killed an estimated 151,700 to 575,400 people worldwide.
In the last decade, several studies from TSRI, Janssen and other institutions have shown that some people are capable of making powerful antibodies that can fight many subtypes of influenza at once by targeting a site on the influenza virusthat does not mutate rapidly. Unfortunately, these "broadly neutralizing antibodies," or bnAbs, are rare.
Still, the tantalizing existence of broadly neutralizing antibodies led Janssen and TRSI to try creating an influenza vaccine specially designed to elicit them.
Researchers zeroed in on a possible target: a protein on the surface of influenza, called hemagglutinin (HA). HA is present on all subtypes of influenza, providing the key viral "machinery" that enables the virus to enter cells. Most importantly, the long "stem" region of HA, which connects the virus to cells, plays such a crucial role that mutations at the site are unlikely to be passed on.
"If the body can make an immune response against the HA stem, it's difficult for the virus to escape," Wilson explained.
Fighting 'Bird Flu' and Other Strains
To create antibodies against the HA stem, the research team looked to influenza's own structure, specifically the universal recognition site of the broadly protective antibody CR9114 in the HA stem (described by Dreyfus et al., Science2012). This vaccine candidate was designed, produced and tested by a team of scientists led by Jaap Goudsmit, head of the Janssen Prevention Center, the paper's first author Antonietta Impagliazzo (responsible for the design) and co-senior author Katarina Radoševi?.
The effort represents the first time scientists have been able to cut off the variable head region of HA, designing features able to stabilize the conformation of the original protein, and at the same time faithfully mimicking the key broadly neutralizing site. The ultimate goal was to use this synthetic version of the HA stem in a vaccine to teach the body to make powerful antibodies against influenza virus, priming it to fight off a variety of flu strains.
The scientists then studied the response of rodent and nonhuman primate models given one of several candidate immunogens. They found that animals given one especially stable immunogen produced antibodies that could bind with HAs in many influenza subtypes, even neutralizing H5N1 viruses ("avian" or "bird" flu).
"This was the proof of principle," said Wilson. "These tests showed that antibodies elicited against one influenza subtype could protect against a different subtype."
Scientists at TSRI studied the structure of the immunogen at every point in the process. Using the imaging techniques of electron microscopy (led by TSRI Associate Professor Andrew Ward and postdoctoral fellow Ryan Hoffman) and x-ray crystallography (led by Wilson and TSRI Staff Scientist Xueyong Zhu), the team showed that the most promising candidate immunogen mimicked the HA stem and that antibodies could bind with the immunogen just as they would with a real virus.
With proof that an immunogen can elicit antibodies against the stem region, Wilson said the next step in this research is to see if the immunogen can do the same in humans.
"While there is more work to be done, the ultimate goal, of course, would be to create a life-long vaccine," Wilson said.
More information: A stable trimeric influenza hemagglutinin stem as a broadly protective immunogen, Science, www.sciencemag.org/lookup/doi/10.1126/science.aac7263

Provided by The Scripps Research Institute

Flu vaccine associated with lower risk of cardiovascular events

Receiving an influenza vaccination was associated with a lower risk of major adverse cardiovascular events such as heart failure or hospitalization for heart attack, with the greatest treatment effect seen among patients with recent acute coronary syndrome (ACS; such as heart attack or unstable angina), according to a meta-analysis published in the October 23/30 issue of JAMA.

27 oct 2013--"Among nontraditional cardiovascular risk factors, there remains interest in a potential association between respiratory tract infections, of which influenza and influenza-like illnesses are common causes, and subsequentcardiovascular events," according to background information in the article. Several epidemiological studies have suggested a strong inverse relationship between influenza vaccination and the risk of fatal and nonfatal cardiovascular events.

Jacob A. Udell, M.D., M.P.H., F.R.C.P.C., of the University of Toronto, and colleagues conducted a meta-analysis of all randomized clinical trials (RCTs) of influenza vaccine that studied cardiovascular events as efficacy or safety outcomes to determine if influenza vaccination is associated with prevention of cardiovascular events. The researchers identified five published and 1 unpublished RCTs of 6,735 patients (average age, 67 years; 51 percent women; 36 percent with a cardiac history; average follow-up time, 7.9 months) that met inclusion criteria for the study. Analyses were stratified by subgroups of patients with and without a history of acute coronary syndrome(ACS) within 1 year of randomization.

In the 5 published RCTs, 95 of 3,238 patients treated with influenza vaccine (2.9 percent) developed a major adverse cardiovascular event compared with 151 of 3,231 patients (4.7 percent) treated with placebo or control within 1 year of follow-up, an absolute risk difference favoring flu vaccine of 1.74 percent. The addition of the unpublished data did not materially change the results (2.9 percent influenza vaccine vs. 4.6 percent placebo or control).

In a subgroup analysis of 3 RCTs of patients with pre-existing coronary artery disease (CAD), the risk of major adverse cardiovascular events among patients with a history of recent ACS was especially lower with vaccine (10.3 percent influenza vaccine vs. 23.1 percent placebo or control), an absolute-risk difference of 12.9 percent, compared to patients with stable CAD (6.9 percent influenza vaccine vs. 7.4 percent placebo or control). Results were similar with the addition of unpublished data.

"Within this global meta-analysis of RCTs that studied patients with high cardiovascular risk, influenza vaccination was associated with a lower risk of major adverse cardiovascular events within 1 year. Influenza vaccination was particularly associated with cardiovascular prevention in patients with recent ACS. Future research with an adequately powered multicenter trial to confirm the efficacy of this low-cost, annual, safe, easily administered, and well-tolerated therapy to reduce cardiovascular risk beyond current therapies is warranted," the authors conclude.

In an accompanying editorial, Kathleen M. Neuzil, M.D., M.P.H., of PATH, Seattle, discusses the importance of improving influenza vaccination coverage.

"There are proven ways to increase vaccination coverage, including expanding access through nontraditional settings (e.g., pharmacy, workplace, school venues), improving the use of evidence-based practices at medical sites (e.g., standing orders, reminder or recall notification), and using immunization registries. One of the most consistent and relevant findings of operational research is that recommendation for vaccination from physicians and other health care professionals is a strong predictor of vaccine acceptance and receipt among patients. While few are in a position to develop new influenza vaccines, all health care practitioners can recommend influenza vaccine to their patients. Doing so will help achieve the goal of 100 percent vaccination for the 2013-2014 influenza season."

More information: DOI: 10.1001/jama.2013.279206
DOI: 10.1001/jama.2013.279207

Provided by The JAMA Network Journals

Doubts Grow Over Flu Vaccine in Elderly

By BRENDA GOODMAN
02 sept 2008--The influenza vaccine, which has been strongly recommended for people over 65 for more than four decades, is losing its reputation as an effective way to ward off the virus in the elderly.
A growing number of immunologists and epidemiologists say the vaccine probably does not work very well for people over 70, the group that accounts for three-fourths of all flu deaths.
The latest blow was a study in The Lancet last month that called into question much of the statistical evidence for the vaccine’s effectiveness.
The authors said previous studies had measured the wrong thing: not any actual protection against the flu virus but a fundamental difference between the kinds of people who get vaccines and those who do not.
This contention is far from universally accepted. And even skeptics say that until more effective measures are found, older people should continue to be vaccinated, because some protection against the flu is better than none.
Still, the Lancet article has reignited a longstanding debate over claims that the vaccine prevents thousands of hospitalizations and deaths in older people. “The whole notion of who needs the vaccine and why is changing before our eyes,” said Peter Doshi, a doctoral candidate at M.I.T. who published a paper on the historical impact of influenza in May in The American Journal of Public Health.
The Lancet paper, by Michael L. Jackson and colleagues at the Group Health Center for Health Studies in Seattle, was based on an analysis of medical charts of thousands of elderly members of an H.M.O.
The study found that people who were healthy and conscientious about staying well were the most likely to get an annual flu shot. Those who are frail may have trouble bathing or dressing on their own and are less likely to get to their doctor’s office or a clinic to receive the vaccine. They are also more likely to be closer to death.
Dr. David K. Shay of the Centers for Disease Control and Prevention, a co-author of a commentary that accompanied Dr. Jackson’s study, agreed that these measures of health and frailty “were not incorporated into early estimations of the vaccine’s effectiveness” and could well have skewed the findings.
Not everyone is sold on the significance of the Lancet study. “I think this is another study that provides interesting findings and raises questions,” said Dr. Kristin Nichol, chief of medicine at the Veterans Affairs hospital in Minneapolis. “I don’t think we know yet what the final word is on influenza vaccinations in the elderly.
“I really feel, and I feel very strongly about this, that the public health message should be that vaccines are effective,” she continued. “I don’t think that science is necessarily best hashed out in the media.”
Dozens of studies since 1960 have supported the view that the vaccine is a powerful protector of the elderly, cutting their risk of dying in winter from any cause by almost 50 percent and reducing the risk of hospitalization by nearly 30 percent.
Those findings came from observational studies, in which scientists make inferences about the effect of a treatment on a population by comparing what happens to a group that has the treatment with what happens to an apparently similar group that does not.
There has been only one large study that compared the flu vaccine with a placebo for two random groups of older people in which neither the patients nor the scientists knew which group was receiving which injection. It came to a different conclusion from the observational studies.
Conducted by Dutch researchers and published in 1994 in The Journal of the American Medical Association, it found that in those 60 to 69, the vaccine prevented influenza about 57 percent of the time. In those over 70, the vaccine prevented the flu just 23 percent of the time, though the estimate is imprecise because the study was not designed to look at this age group.
But the influenza vaccine was never put through more placebo-controlled trials, which are considered the gold standard in medical evidence. “I think the evidence base we have leaned on is not valid,” said Lone Simonsen, an epidemiologist and visiting professor at the George Washington University School of Public Health and Health Services in Washington who was not connected with the Lancet study.
In 2005, Dr. Simonsen, who was then at the National Institute of Allergy and Infectious Diseases in Bethesda, Md., published a paper in The Archives of Internal Medicine that found something odd: even though the percentage of older people who got an annual flu shot more than tripled from 1980 to 2001, there was no corresponding drop in the death rate.
That paper included one of the first estimates of how many deaths are actually caused by the flu — a number hard to pin down because doctors seldom confirm flu in their patients with lab tests. Using a statistical model and the best available data, Dr. Simonsen found that influenza probably causes just 5 to 10 percent of all winter deaths in the elderly. But earlier studies had found that the flu vaccine cut an elderly person’s risk of dying by 50 percent.
“You don’t have to do a whole lot of math to realize that doesn’t add up,” said Dr. Lisa A. Jackson of the Group Health Center for Health Studies in Seattle, who has also studied the effectiveness of the flu vaccine in the elderly.
Dr. Jackson at first tried to tease out underlying differences between vaccinated and unvaccinated elderly people by using medical codes — a numerical shorthand that doctors use to classify and record what is wrong with their patients. She and other researchers reasoned that patients with codes for cancer or heart disease, for example, might be very sick, thus skewing the results. When they adjusted for those codes, however, the differences between the vaccinated and unvaccinated groups became even more pronounced. The vaccine looked even more protective.
It was Michael L. Jackson’s thesis project, at the University of Washington, that revealed the flaw in using the codes to differentiate patients.
For the project, Mr. Jackson (no relation to Lisa Jackson) and three other researchers spent almost three years reading medical charts and examining X-rays. They discovered that health-conscious people were more likely to get medical codes for things like heart disease and cancer simply because they went to the doctor more often. But when Mr. Jackson adjusted for measures of frailty — things like lung function, whether people needed help bathing or dressing, and what kinds of medications they took — he found that vaccination had little effect on older people’s risk for pneumonia, the most dangerous complication of the flu.
That finding has a biological basis. Vaccines work by priming the immune system to recognize and respond to incoming threats. Because the immune system slows down with age, older adults do not respond as well to vaccines as younger adults.
A recent study by Dr. Wilbur H. Chen and colleagues at the Center for Vaccine Development at the University of Maryland School of Medicine found that elderly participants needed four times the amount of antigens given in a standard dose of the flu vaccine to have the same kind of immune response as healthy adults under 40. They presented their findings in May at the Annual Conference on Vaccine Research in Baltimore.
Despite these findings, Dr. Shay said the C.D.C. had no plans to change its vaccine recommendations, though he added that the agency had financed studies to look for more effective influenza vaccines for the elderly.
Dr. Simonsen, the epidemiologist at George Washington, said the new research made common-sense infection-control measures — like avoiding other sick people and frequent hand washing — more important than ever. Still, she added, “The vaccine is still important. Thirty percent protection is better than zero percent.”

Flu Vaccine Doesn't Protect Seniors From Pneumonia

By Steven Reinberg
02 aug 2008 -- Flu vaccine may not protect older people from pneumonia once they get the disease, researchers report.
Older, frail adults are more susceptible to getting the flu, even if they have been vaccinated, and once getting the flu, they are more susceptible to such complications as pneumonia. It had been thought that flu vaccine would prevent flu -- and pneumonia -- across all groups of seniors, but this benefit appears to be largely confined to younger, healthier seniors.
"In seniors, flu vaccine was not linked to a reduced risk of pneumonia," said lead researcher Michael L. Jackson, a postdoctoral fellow at the Group Health Center for Health Studies in Seattle.
Jackson still recommends that seniors get flu vaccine, however. "There have been good randomized trials that show, at least in healthy seniors, that the vaccine reduces the risk of influenza," he said. "However, earlier studies have overestimated how well the vaccine works in reducing complications of influenza. So, the vaccine may not reduce the risk of complications as much as previously thought," he said.
Among young healthy seniors, the vaccine reduces the risk of flu, Jackson said. "When you look at the total population of seniors, which includes people over 75 and people that have chronic health diseases -- lung disease, heart disease, diabetes, and things like that -- we don't know if the vaccine is effective in the seniors," he said. "People with these chronic diseases are more susceptible to getting the flu, and they are more likely to develop pneumonia if they do get influenza."
The report is published in the Aug. 2 issue of The Lancet.
For the study, Jackson's team collected data on 1,173 people between the ages of 65 and 94 who developed pneumonia They compared these individuals with 2,346 people who did not get pneumonia. Both groups had similar rates of flu vaccination over the three seasons of studies, the researchers say.
The researchers found that vaccinated seniors who got the flu were as likely to develop pneumonia as unvaccinated seniors who got the flu.
Dr. Pascal James Imperato, dean of the master of public health program at the State University of New York Downstate Medical Center in New York City, was not surprised by these results.
"We know that elderly people do not form sufficient antibodies to certain vaccines, the flu vaccine included," Imperato said. "In addition, people in their 70s and 80s and 90s are more prone to pneumonia with or without influence. A number of these pneumonias may be secondary to other causes aside from influenza."
Even though many of the elderly will not develop sufficient antibodies to the flu vaccine, getting the shot is still worthwhile, Imperato said. "Having many people vaccinated builds up a herd immunity to disease, and you create barriers to transmission," he added.
Dr. Marc Siegel, a clinical associate professor of medicine at New York University School of Medicine in New York City, said the results of this study fly in the face of prevailing wisdom.
Siegel noted that 36,000 people in the United States die each year from the flu. "Over 90 percent of them are elderly," he said. "We give the flu shot primarily to prevent elderly deaths.
The effectiveness of the flu vaccine varies year to year, however, depending on how good a match it is for the circulating strains of influence. "In the best years, the flu vaccine is really only 40 to 60 percent effective," Siegel added.
In addition, Siegel thinks that the flu vaccine protects against other complication including respiratory diseases, which can also be fatal. "There are plenty of flu-related complications that are life-threatening besides pneumonia," he said.
"This study is a reminder that flu vaccines are not a panacea, but they are valuable, because they cut down on the incidence of influenza," Siegel said. "Flu shots definitely cut down on the number of flu-related deaths."

ACC: Flu Vaccine Less Effective in Heart Failure Patients

By Todd Neale
CHICAGO, March 31 -- Heart failure patients may not have as strong an immune response to flu vaccine as healthy patients, researchers found.
Patients with heart failure had a significantly (P=0.017) lower antibody response to one of the three influenza virus strains found in the vaccine compared with healthy patients, Orly Vardeny, Pharm.D., of the University of Wisconsin in Madison, told attendees at the American College of Cardiology meeting here.
"We hypothesize that [the impaired response] has something to do with the pathophysiology of heart failure itself, meaning some neurohormone levels are increased, such as norepinephrine and angiotensin II," she said, "and we're specifically studying the effects of norepinephrine or beta-adrenergic mechanisms in vaccine responses."
Dr. Vardeny added, however, that patients with heart failure should not stop getting immunized on the basis of these findings.
"We're saying in fact that they should, but that maybe more preventative measures should be taken as well," she said.
She said that it has been previously established that heart failure patients were at an increased risk for developing influenza, which is why yearly vaccination is recommended for them.
But there are still high numbers of hospitalizations and deaths from influenza in heart failure patients, Dr. Vardeny said.
To explore this issue, Dr. Vardeny and colleagues examined the immune responses to the 2006-2007 influenza vaccine in 29 heart failure patients (nine ischemic and 20 nonischemic) and 17 healthy controls of similar age and gender.
The heart failure patients had all been stable on a drug therapy regimen for at least 30 days.
The researchers measured blood antibody levels to three influenza strains -- H1N1, B/Shanghai, and H3N2 -- and T-cell responses -- gamma interferon and IL-10 production -- before and then two to four weeks after immunization.
Heart failure patients had a significantly (P=0.001) greater increase in IL-10 production but similar gamma interferon responses compared with the healthy controls.
All patients showed seroprotection -- at least a four-fold increase in antibody production to at least one viral strain -- following immunization. Overall, heart failure patients had lower levels of seroconversion, but the difference from healthy patients did not reach statistical significance.
However, antibody response to H3N2, the newest strain added to the vaccine, was significantly (P=0.017) lower in patients with heart failure.
Antibody responses to the other two strains showed a trend toward being lower in heart failure patients than in healthy controls, but the differences were not statistically significant.
The H3N2 strain had not been included in any previous vaccines and, therefore, neither the heart failure patients nor the healthy controls had been exposed to it before this study.
The finding of an impaired immunological response to this strain in heart failure patients suggests that immunological memory is particularly important in conferring protection against influenza in these patients, said Dr. Vardeny.
These findings also imply that "heart failure goes beyond the heart, that there are other systems challenged by [the condition]," commented Janet Wright, M.D., a vice president for science and quality at the ACC, who moderated the session at which the results were discussed.
The study was supported by the NIH.
Neither Dr. Vardeny nor Dr. Wright made any disclosures.
Primary source: American College of CardiologySource reference:Vardeny O, et al "Decreased antibody responses to influenza vaccine in heart failure" ACC Meeting 2008; Abstract 1002-35.