Development and production of yearly influenza vaccines in current use relies on a bit of chance and lengthy production times. This is due to the fact that the vaccine is not designed to protect against all strains of flu, but instead targets several particular strains predicted to be most active during the upcoming flu season. The reason for this is that the immunogenic portions of the virus that elicit immunity via vaccination are prone to rapid mutation. This forces vaccine producers to augment the composition of their vaccines annually in an attempt to provide the best coverage possible each flu season.
Could targeting a less mutation prone component of the influenza virus lead to a better vaccine with broader coverage and longer lasting effect? Recent research into alternative vaccine models aims to explore this very question. These newer models use engineered “immunogens” to induce host immune response against less mutation prone viral antigens. Animal studies of these new vaccine models show promise, but further investigation is needed to test their efficacy in humans.
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