What Everyone Needs to Know Q&A: As the United States deals with the worst nationwide flu outbreak in nearly a decade, we want to know:
Are we getting any closer to an influenza vaccine that does not have to be changed every year?
Significant resources and focus have been devoted to influenza vaccine development, particularly improvements to the vaccine’s production and effectiveness. Development of a universal influenza vaccine is high on this priority list as well, but it has proven challenging. A universal vaccine will require the ability to identify a part of the virus that does not change and also sparks a good enough antibody response to provide protection. Some vaccine candidates are focusing on a different part of the hemaglutinin protein: Current vaccines use the top, or head, of the protein, whereas the newer candidate vaccines use the more stable stalk. Other vaccine candidates focus on different virus proteins altogether, but these options would only make infection less severe, not prevent infection entirely. Last, some vaccine candidates use a helper substance, or adjuvant, that helps boost the antibody response for a wider range of proteins that may be shared across different influenza strains. These new possibilities may mean that a new vaccine would not be needed every year, but most of these vaccine candidates are still in the preclinical or early clinical trial phases.
Another focus for influenza vaccine development is speed—finding a way to manufacture more vaccine, faster. The current vaccine’s dependence on eggs for vaccine production has made it difficult to scale- up production when need is greatest, especially in lower income countries. Some new vaccines do not require the use of eggs to grow influenza virus; these are known as cell- culture influenza vaccines.
[Page 146-7, Vaccines: What Everyone Needs to Know by Kristen A. Feemster]
Image credit: “Fruit Thermometer Vitamin C Cold Flu Outbreak” by HoliHo. CC0 via Pixabay.
