Changes

Influenza viruses are always changing. Therefore, influenza vaccines are updated every year, and an annual vaccination is recommended.

Influenza viruses are always changing. Therefore, influenza vaccines are updated every year, and an annual vaccination is recommended.

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Since production of the vaccine must begin many months before the influenza season starts models of the population genetics of the virus must be produced.<ref>http://www.nature.com/nrd/journal/v5/n3/full/nrd1988.html Influenza vaccines</ref> The success of vaccinations programs is dependent on the accuracy of these predictions.<ref>http://www.nature.com/news/2003/030324/full/030324-5.html Flu changes modeled</ref> The [[National Institute of Health]] recently assigned $26 million to establish a research center to better develop molecular models of influenza.<ref>http://www.spiritindia.com/health-care-news-articles-8024.html $26 million NIH contract to establish new flu/bird flu Center of Excellence</ref>

Since production of the vaccine must begin many months before the influenza season starts models of the population genetics of the virus must be produced.<ref>http://www.nature.com/nrd/journal/v5/n3/full/nrd1988.html Influenza vaccines</ref> The success of vaccinations programs is dependent on the accuracy of these predictions.<ref>http://www.nature.com/news/2003/030324/full/030324-5.html Flu changes modeled</ref> The National Institute of Health recently assigned $26 million to establish a research center to better develop molecular models of influenza.<ref>http://www.spiritindia.com/health-care-news-articles-8024.html $26 million NIH contract to establish new flu/bird flu Center of Excellence</ref>

==Herd immunity and mandatory vaccination==

==Herd immunity and mandatory vaccination==