Cold and flu season has already started and doctors are saying it's time to come in for a flu shot. But have you ever wondered why you need to get a new shot every year?
In the video above by DNews, host Julia Wilde attempts to explain why it's taking so long to create a vaccine that will make us immune to the influenza virus once and for all.
Wilde points out that influenza is a mutating virus, which up until now researchers have only been able to treat strain by strain. Since scientists hypothesize which strain will be strongest each year, the effectiveness of the vaccine can be questionable. In January of this year, a study revealed that the 2014 vaccine was only 23 per cent effective.
This year's vaccine is expected to be significantly more effective as it covers four strains of the influenza virus.
And perhaps it won't be long until the universal vaccine is available to everyone. Earlier this year, researchers announced they are working on a new vaccine using a part of the influenza virus that does not mutate as easily as the protein hemagglutinin, which is currently used in the flu vaccine, TIME reports.
Are you planning to get a flu shot this year? Let us know in the comments below.
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