Study Design And Sampling
Following randomization, a total of 800 donors received either Fluquadri , Fluad , Fluzone-High-Dose or Flublok . All vaccines contained antigens from A/Michigan/45/2015 , A/Hong Kong/4801/2014 , and B/Brisbane/60/2008 quadrivalent vaccines contained additional antigens from B/Phuket/3073/2013 . Five years of prior vaccination history for each subject was based on clinical records or self-reporting .
Iv1 Older Adults With Risk Factors
The majority of studies reviewed for this report were conducted with ambulatory, community-dwelling older adults without immune suppressing diseases and who were not using immune suppressing medication. Also, the mean age of the participants is in the early 70s, when the immune response is expected to be better than for older adults. Studies need to be completed in older adults with immune suppressing conditions or using immune suppressing medications, people who are institutionalized, and adults who are 75 years of age and older to determine whether these vaccines are as effective in these cohorts as they are in the younger, healthier cohorts of seniors.
How Safe Is Fluzone High
Some side effects were reported more frequently after vaccination with trivalent Fluzone High-Dose than after standard-dose inactivated flu vaccines. The most common side effects experienced during clinical studies were mild and temporary, and included pain, redness at the injection site, headache, muscle aches, and malaise. Most people had minimal or no side effects after receiving the Fluzone High-Dose. In a study comparing Fluzone High-Dose Quadrivalent with trivalent Fluzone High-Dose, some of these side effects were slightly more common with the quadrivalent vaccine, but most were mild and resolved within a few days.
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Diverse Adjuvants Can Induce Broad Cross
To evaluate the breadth of neutralization, sera were analyzed for their ability to neutralize the heterologous H1N1 viruses A/Beijing/262/95 and A/Brisbane/59/2007 . Mice immunized with HA-NP in the absence of adjuvant failed to induce detectable neutralizing or HAI antibody responses. All adjuvants elicited neutralizing antibodies in immunized mice against the heterologous viruses . Furthermore, AF03 and AF04 induced cross reactive HAI responses , suggesting that the breadth elicited following immunization with the HA-NP can be further improved with the inclusion of specific adjuvants.
Breadth of immune responses induced by adjuvants used in immunization.
Adjuvants that induced high neutralizing titers against homologous virus were selected for analyses against two additional H1 viruses, Beij95 and Bris07. Lentivirus reporter neutralization and HAI were used to measure the breadth of neutralization in mouse serum following two immunizations. Mean ± SEM is graphed. **** p< 0.0001 *p< 0.05.
Rve During Peak Influenza Activity

In the restricted 20172018 season analysis , the rVE of aIIV3 versus IIV4 was 18.8 and the rVE of aIIV3 versus HD-IIV3 was 8.2 . During the restricted 20182019 season, aIIV3 rVE values were 26.6 and 5.7 versus IIV4 and HD-IIV3, respectively. Age subgroup analyses during the restricted influenza seasons yielded similar estimates in both seasons . The results using the broad definition of influenza-related medical encounters were also similar .
Adjusted rVE of aIIV3 Versus Comparators During Restricted Influenza Seasons , by Age Groupa
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What’s The Research Behind These Shots Do They Work
Research indicates that high-dose flu vaccines, such as Fluzone High-Dose and FLUAD, have improved a patient’s protection against the flu.
A peer-reviewed study published in The New England Journal of Medicineand sponsored by Sanofi, the company behind Fluzone High-Dose, found that the high-dose vaccine is about 24% more effective than the standard shot in preventing the flu.
An observational study in 2013 found that FLUAD is 51% effective in preventing flu-related hospitalizations for patients 65 and older.
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Kristin Englund, an infectious disease physician at the Cleveland Clinic, noted that some hospitals might carry only Fluzone High-Dose because there are more studies on it and it’s been on the market longer than FLUAD.
There are no studies that do a comparative analysis between the two vaccines. There also aren’t any studies that test the high-dose vaccine on younger patients, which is why the FDA licensed the vaccines only for people 65 and older.
Will these super-vaccines cost more money?
Schaffner said that because both vaccines are more elaborate than the normal dose, they cost more to make.
Both Fluzone High-Dose and FLUAD are covered by those who qualify for Medicare with no out-of-pocket cost.
How Effective Are Flu Vaccines In Children
Vaccination has been found in most seasons to provide a similar level of protection against flu illness in children to that seen among adults.
In several studies, flu vaccine effectiveness was higher among children who received two doses of flu vaccine the first season that they were vaccinated compared to partially vaccinated children who only received a single dose of flu vaccine. However, in some seasons, partially vaccinated children still receive some protection.
In addition to preventing illness, flu vaccine can prevent severe, life-threatening complications in children, for example:
- A 2014 study showed that flu vaccine reduced childrens risk of flu-related pediatric intensive care unit admission by 74% during flu seasons from 2010-2012.
- In 2017, a study in the journal Pediatrics external icon was the first of its kind to show that flu vaccination also significantly reduced a childs risk of dying from flu. The study, which looked at data from four flu seasons between 2010 and 2014, found that flu vaccination reduced the risk of flu-associated death by half among children with underlying, higher risk medical conditions and by nearly two-thirds among healthy children.
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Immunostaining Of Tfh Cells And Plasmablasts
Whole blood samples were stained with indicated antibodies . The TFH panel contained: anti-human CD3-PE/Dazzle 594 , CD4-AlexaFluor700 , CXCR5-PerCPCy5.5 , CD45RA-FITC , CCR6-BV605 , CXCR3-APC , PD-1-BV711 , and ICOS-PE . A separate plasmablast panel contained: CD19-BV510 , CD27-FITC , and CD38-BV421. Cells were acquired by flow cytometry .
What Are Fluzone High
Dr. William Schaffner, an infectious diseases specialist at Vanderbilt University Medical Center, said that although the two vaccines have the same outcome, they work a little differently.
Fluzone High-Dose contains four times the antigen that’s in a standard dose, effectively making it a stronger version of the regular flu shot. FLUAD pairs the regular vaccine with an adjuvant, an immune stimulant, to cause the immune system to have a higher response to the vaccine.
The data indicates that no matter what flu strain is out there, it provides more protection for older people, Schaffner said.
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What Is The Difference Between Fluzone High
Fluzone High-Dose Quadrivalent contains four times the antigen, the part of the vaccine that helps your body build up protection against flu viruses, than Fluzone Quadrivalent and other standard-dose inactivated flu vaccines. The higher dose of antigen in the vaccine is intended to give people 65 years and older a better immune response to vaccination, and therefore, better protection against flu. Both Fluzone High-Dose and Fluzone Quadrivalent are produced by the same manufacturer and are quadrivalent vaccines. There are a number of other flu vaccines produced by other manufacturers.
Who Needs To Get A High
Fluzone High-Dose Quadrivalent is only FDA-approved for people over 65, so if youre younger than that, you should stick to the regular dose vaccine. Speak with your healthcare provider to decide which available flu vaccine is the best option for you.
If youre over 65 and questioning your flu vaccines options, contact your healthcare provider. Theyll let you know which of the three CDC-recommended flu vaccines for people over 65 is the best for you.
If your pharmacy or healthcare providers office doesnt have high-dose flu vaccines in stock, its recommended to get vaccinated with a regular dose vaccine instead of waiting for Fluzone High-Dose Quadrivalent to be restocked. A regular dose vaccine will still offer you protection against the flu.
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Why The Flu Vaccine Matters For Older People
The CDC currently recommends that everyone who is 6 months and older receive an annual flu vaccine, but the agency particularly stresses the importance of people aged 65 and up getting vaccinated.
People in this age group are at higher risk of developing serious complications of the flu, including pneumonia and multi-organ failure, compared to those who are younger and healthy, due to changes in the immune system with age.
An estimated 70- to 80% of flu-related deaths have happened in people who are 65 and up, and 50- to 70% of hospitalizations due to the flu happen in this age group.
How Does Cdc Measure How Well Flu Vaccines Work

CDC typically presents vaccine effectiveness as a single point estimate: for example, 60%. This point estimate represents the reduction in risk provided by a flu vaccine. CDC vaccine effectiveness studies measure different outcomes. For example, outcomes measured can include laboratory-confirmed flu illness , hospitalizations or intensive care unit admissions. For these outcomes, a VE point estimate of 60% means that on average the flu vaccine reduces a persons risk of that flu outcome by 60%.
In addition to the VE point estimate, CDC also provides a confidence interval for this point estimate, for example, 60% . The confidence interval provides a lower boundary for the VE estimate as well as an upper boundary . One way to interpret a 95% confidence interval is that if CDC were to repeat this study 100 times , 95 times out of 100, the confidence interval would contain the true VE value. Another way to look at this is that there is a 95% chance that the true VE lies within the range described by the confidence interval. This means there is still the possibility that five times out of 100 the true VE value could fall outside of the 95% confidence interval.
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When Adjuvants Didn’t Work
However, there have been notable cases where adjuvanted influenza vaccines have had to be withdrawn or the recommended usage altered . Separating the specific contribution of adjuvant to the adverse effect is complicated as they are always administered in combination with the antigen. However, it is likely that the adjuvant played a role in the adverse effects seen. There are a range of possible mechanisms by which the inclusion of an adjuvant might have increased the incidence of severe adverse effects including increased inflammation caused by the adjuvant, as seen with LT adjuvanted Nasalflu, or altered responses to the antigen including increased immunogenicity of sub-dominant epitopes, as possibly seen with AS03 and narcolepsy.
AS03 adjuvanted H1N1 vaccine and narcolepsy
Heat labile enterotoxin adjuvanted vaccine and Bell’s Palsy
Types Of Flu Shots For Seniors
As you age, its normal for your body to respond less to vaccines. Older people who get the flu shot generally have a weaker immune response than younger people who get the vaccine. But the vaccine is still effective in reducing medical visits and hospitalizations for the flu.
Some flu shots are designed to cause a stronger immune response. These flu vaccines can offer greater protection for people 65 and older. There are two types of senior flu shots that are licensed only for people 65 and older.
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If Ive Had A Flu Vaccine In The Past Do I Need To Have Another One
Yes. Even if youve received an influenza vaccine in the past, youll likely need to get another one each year.
In fact, the Centers for Disease Control and Prevention recommends that most people older than 6 months of age receive a flu vaccine, such as Fluzone, every year. This is for two main reasons.
First, many different strains of influenza circulate each year. And these strains are continuously changing. Each year, scientists try to determine which strains of the flu will be the most common in the upcoming flu season. Then these strains are put into flu vaccines, such as Fluzone. So flu vaccines change from year to year.
Second, the protection provided by the vaccine wanes over time. This effect happens in everyone, but its more likely to occur in older adults .
If you have questions about getting an annual flu shot, talk with your doctor or pharmacist.
Financial And Insurance Assistance
If you need financial support to pay for Fluzone, or if you need help understanding your insurance coverage, help is available.
Sanofi Pasteur, Inc., the manufacturer of Fluzone, has an online tool that may help you estimate the cost of Fluzone High-Dose Quadrivalent. For more information about this, see the manufacturers website.
For additional cost assistance information about Fluzone, visit Medicine Assistance Tools site or talk with your doctor or pharmacist.
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Trivalent And Quadrivalent Shots Made With Adjuvant
These shots, called Fluad and Fluad Quadrivalent, are another option for flu vaccines that are approved for people ages 65 and older. It includes an ingredient called adjuvant, which also creates a stronger immune system response.
These flu vaccines are slightly different because they protect against four different strains of the flu virus .
Because of this, these vaccinations can provide broader protection from infection.
Options are below.
Future Of Adjuvanted Flu Vaccines
The biggest question is whether any of the adjuvants in development will be included in a licensed commercial product. There are two hurdles to overcome the cost of manufacturing the adjuvant to GMP standard at a scale required for influenza vaccine and the risk of an unforeseeable adverse effect occurring when the vaccine is deployed at a population level. Realistically for the current generation of influenza vaccines, particularly in the face of existing adjuvants from the major vaccine manufacturers, in our opinion it is unlikely that a new adjuvant will be included in a seasonal influenza vaccine. However, there is still scope for research into adjuvants to support the next generation of influenza vaccines. Speculatively this could focus on the following areas:
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Fluad Quadrivalent Influenza Vaccine 2022
Seqirus, Inc. Fluad Quadrivalent Influenza Vaccine consists of an inactivated, quadrivalent influenza virus antigen produced in eggs and an oil-in-water emulsion adjuvant, MF59. Fluad is the first FDA-approved seasonal flu shot containing an adjuvant, an immune-enhancing ingredient. Fluad is indicated for active immunization against influenza disease caused by influenza virus subtypes A and types B contained in the vaccine. Compared to FLUAD, FLUAD QUADRIVALENT includes an additional B strain to help prevent disease caused by all four influenza strains represented in the vaccine.
It was approved by the U.S. FDA in 2020. For the 2021-2022 flu season in the Northern Hemisphere, the FDA recommended a quadrivalent egg-based vaccine that includes these components. FLUAD QUADRIVALENT is approved for use in persons 65 years of age and older.
The immune-enhancing ingredient in Fluad is an oil derived from squalene. Squalene is a naturally occurring substance found in humans, animals, and plants. Adults aged 65 and older with an aging immune system might have a lower immune response to traditional flu vaccines than younger adults. Squalene, the immune-enhancing ingredient, provides a robust immune response to help adults’ immune systems recognize and respond to the flu virus.
The U.S. CDC published updated flu vaccine schedules on February 17, 2022.
New Jersey-based Seqirus is a leader in the fight against influenza with an innovative portfolio of influenza products.
How Adjuvants Work

Before describing what is known of the mechanism of specific adjuvants included in licensed influenza vaccines, it is necessary to give a brief overview of their general mechanism of action . Fundamentally, adjuvants improve the ability of the host immune system to recognise the administered antigen as foreign and respond to it beyond this simple description they are extremely diverse in their molecular and cellular mechanisms of action.
The first requirement is for the vaccine antigen to be seen by the immune system. One problem is that soluble antigen is quickly cleared by the lymphatics and therefore is never seen by the immune system. Adsorbing the antigen onto an insoluble complex or in an oil-in-water emulsion leads to the retention of antigen at the injection site. In theory, the antigen/adjuvant depot can then be sampled by antigen presenting cells, which then take antigen to the lymph nodes. However, recent studies in mice have shown that removing the site of the depot even as early as two hours after immunisation had no negative effect on the immune response, suggesting that formation of a depot at the injection site is not essential.36
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How Fluzone Works
Fluzone is an influenza vaccine that helps to protect you from the flu. Vaccines help prepare your body to fight off an infection by exposing your immune system to a particular virus.
The flu can be caused by many different strains of influenza virus, which circulate around the globe each flu season. Each year, scientists try to determine which strains of the flu will be the most common in the upcoming flu season. Then these strains are put into vaccines, such as Fluzone.
Fluzone contains inactivated influenza virus. When you get an inactivated flu vaccine, your immune system gets exposed to the inactivated flu virus. This prompts your immune system to make antibodies against the strains of flu contained in the vaccine.
Antibodies are proteins that help your body fight infections, such as influenza. Once you have antibodies to the flu, if youre exposed to it, your body will be more prepared to fight it off.
Does Fluzone High
Studies published in the Journal of Infectious Diseases conducted during the 2017-2018external iconand 2018-2019external icon flu seasons among Medicare beneficiaries aged 65 years and older found that Fluzone High-Dose and FLUAD provided greater protection against flu-related hospitalizations than standard-dose, egg based vaccines in both seasons.
There are many vaccine options to choose from, but the most important thing is for all people 6 months and older to get a flu vaccine every year. If you have questions about which vaccine is best for you, talk to your doctor or other health care professional.
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