There were 7,000 confirmed cases of the flu in the United States by the end of November – double the amount from the same time the prior year, according to the Centers for Disease Control and Prevention. University of Washington School of Medicine researchers are hoping to one day offer an alternative to the annual flu shot: a DNA vaccine. The vaccine could offer long-lasting protection from all flu virus strains – even as viruses genetically change.

A DNA vaccine could instruct a person’s skin cells to generate antigens and induce antibodies and T cell responses to fight the flu, according to UW Medicine. A gene gun device could inject the vaccine right into skin cells. With the universal vaccine, people might not have to get a flu shot every year.
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The DNA vaccine is able to get around genetic changes in flu strains by “using genetic components of influenza virus – the conserved areas – which do not change,” according to UW Medicine. The DNA vaccine doesn’t just repel a virus but finds infected cells and kills them. The research team tested the vaccine on primates, and found T cell responses were so fast the primates just did not get sick.
Department of Microbiology professor Deborah Fuller, in whose laboratory this research took place, said in a statement, “With the immunized groups, we found that using this conserved component of the virus gave them 100 percent protection against a previous circulating influenza virus that didn’t match the vaccine.”
This universal vaccine could be ready for rapid deployment in case of a deadly pandemic flu strain, and has a production time of around three months as opposed to the nine months required for the United States-approved vaccine for flu season. The DNA-based approach could also offer a mechanism for vaccines for other viruses like Zika.
The vaccine could still be five to 10 years away – UW Medicine said that’s about as long as it takes from promising laboratory results to commercial viability.
The journal PLOS One published the research this month. 17 researchers from institutions around the United States contributed to the paper.