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Fighting The Flu, Respiratory Illnesses

If vaccines undergo years of studies, how is it that a new annual or pandemic flu shot comes out every year?

Because influenza viruses are constantly evolving, and the viruses that circulate among people often change from one year to another, flu vaccines change annually. Scientists around the world collect samples to identify which flu strains are most likely to be circulating in the next flu season and here in the United States, we get our flu strains from the southern hemisphere.

In February—well before a new flu season begins—the U.S. Food and Drug Administration recommends the different strains of influenza viruses that should be included in vaccines that are going to be produced for the upcoming U.S. flu season starting in the fall.  These seed viruses are produced and then distributed to manufacturers to be grown and included in the upcoming flu vaccine. During this vaccine development, manufacturers and the FDA test for potency and safety, as well as quality control tests such as sterility.

The process of flu vaccine production stays the same every year and the only thing that changes is the seed strain of influenza that’s estimated to be circulating in the coming year.  The process used to produce pandemic vaccine (such as the H1N1 vaccine) is identical to the process for producing any other seasonal flu vaccine.

Once a seasonal or pandemic vaccine has been developed and tested, the lots are released in the summer for distribution and use by the public in the fall, typically when flu season begins.

For the 2024-2025 season, the influenza vaccine switched from a quadrivalent flu vaccine to a trivalent vaccine. Both trivalent and quadrivalent flu vaccines are expected to offer similar protection against the flu viruses they protect against. B/Yamagata flu viruses have not circulated in the population since March 2020, so protection from trivalent and quadrivalent flu vaccines is expected to be similar. All flu vaccines for the 2024-2025 season are anticipated to be trivalent in the United States.

Source: CDC 2024-2025 Flu Season

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About I Vaccinate

I Vaccinate provides information and tools based on real medical science and research to help Michigan parents protect their kids. Support is provided by the Michigan Department of Health and Human Services and the Franny Strong Foundation.

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You’ve got questions. That’s a good thing.

As parents, determining how best to protect our children can be overwhelming and confusing. We’re here to help.

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Recommended Immunization Schedules

These schedules list the age or age range when each vaccine or series of shots is recommended by the American Academy of Pediatrics (AAP). If your child (birth through 6 years old) or adolescent (age 7 through 18 years old) has missed any shots, talk to your child’s doctor about getting back on track.

Michigan School & Childcare Immunization Requirements

Request your child’s immunization record

The Michigan Care Improvement Registry (MCIR), is an immunization registry managed by MDHHS and reported to by immunization providers. MCIR allows healthcare providers or individuals to access their immunization records regardless of their location in Michigan. This system also helps to track local and state immunization rates of Michigan residents to ensure immunity to vaccine-preventable illnesses. MCIR is a lifespan registry that includes infant through adult records.

For your appointment

Before, during, and after pregnancy protection
When you’re pregnant, you share everything with your baby. That means when you get vaccines, you aren’t just protecting yourself — you are giving your baby some early protection, too. The CDC has guidelines for the vaccines you and your baby need before, during, and after pregnancy.
From the CDC

Get prepared: Before, during, and after your child’s appointment
There are things you can do before, during and after your child’s appointment to make them easier and less stressful for both of you.
From the CDC

Mobile app from the Children’s Hospital of Philadelphia
The Vaccine Education Center at the Children’s Hospital of Philadelphia created a free mobile app called Vaccines on the Go: What You Should Know so you can access credible, science-based information from wherever and whenever you need it.

Find your local Michigan public health department or immunization clinic
See the directory of Michigan’s 45 local public health departments for more information on your child’s immunization record and where to get them vaccinated.

Other Vaccination Organizations & Advocates

Children’s Hospital of Philadelphia
The Vaccine Education Center at Children’s Hospital of Philadelphia provides complete, up-to-date and reliable information about vaccines to parents and healthcare professionals.

Families Fighting Flu
Families Fighting Flu is a nonprofit on a mission to save lives and reduce hospitalizations by protecting children, families, and communities against influenza.

Vaccinate Your Family
Vaccinate Your Family, formerly known as Every Child By Two, is a non-profit organization that advocates for vaccinations.

Shot by Shot
Stories of Vaccine-Preventable Diseases is a collection of stories from people who have been touched by vaccine-preventable diseases.

Voices for Vaccines
Voices for Vaccines is a parent-led organization that supports and advocates for on-time vaccination and the reduction of vaccine-preventable disease.

 

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