The Centers for Disease Control and Prevention (CDC) estimates that the flu infected 2 million to 3.4 million people in the US from October 1, 2021, to January 22, 2022. Thus, seasonal flu vaccines are essential in decreasing the spread of the influenza virus as more individuals gain immunity to the flu through the vaccine. For this reason, the CDC recommends that individuals receive the influenza vaccine yearly starting at 6 months of age. Two weeks after obtaining the flu vaccine, the immune system produces antibodies that bind to an antigen, specifically, the hemagglutinin protein head of the flu virus. The head of the hemagglutinin protein is easily accessible for the antibody, making the vaccine effective, but the head also has a high mutation rate; for this reason, yearly flu shots are necessary to account for the virus’ mutations.
Individuals should receive a flu vaccine annually.
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New research from the Scripps Research Institute studies the structure of the hemagglutinin protein and the ways it can be used to produce a universal flu vaccine. Scientists in the study refer to the location of interest on the virus as the anchor, which is the bottom stem of the virus that does not alter its shape as frequently as the hemagglutinin protein head. The decreased variability in the hemagglutinin anchor leads to the development of a potential flu vaccine that replaces an attack of the virus head with the virus anchor in the vaccine. Lower rates of mutation in the anchor can potentially remove the need to create yearly vaccines because the vaccine developed from the anchor can protect against a broader selection of virus strains. The Scripps Research Institute group detected 50 unique antibodies that bind to the anchor, which can protect against multiple variations of the influenza virus.
Given the significance of the hemagglutinin protein in detecting the influenza virus, another study conducted at the National Institutes of Health Clinical Center is testing a universal flu vaccine that contains the hemagglutinin protein on nanoparticle structures. The clinical trial, currently in phase one, gave a group of participants the traditional flu vaccine and another group of individuals the experimental FluMos-v1 vaccine. While the traditional flu vaccine protects using 4 different strains of the virus each present as one copy, the experimental FluMos-v1 vaccine has five copies of each of the 4 strains, resulting in a more complex vaccine structure and thus a greater immune defense. The beginning phases of the study found that the experimental vaccine stimulated the immune system to produce antibodies against a hemagglutinin protein mutation that was not directly present in the vaccine, which traditional vaccines are not able to do. The current research trial shows promising results for a stronger immune response that can adapt to changes in the virus for individuals receiving the universal flu vaccine.
As the Scripps Research Institute and the National Institutes of Health Clinical Center continue to research the hemagglutinin protein, their new discoveries make great strides in the production of a universal flu vaccine.
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