In June, the CDC recommended hospitals stop using the FluMist Quadrivalent flu vaccine for immunizations leading into the upcoming 2016-2017 flu season. However, new research in mice from Columbia University Medical Center in New York City suggests the vaccine delivery method is indeed effective for offering other types of immunity.
The researchers found Medimmune's intranasal FluMist vaccine triggered an immune cell response in the lungs of mice that gave them long-term protection against multiple strains of the flu — even strains not contained in the vaccine.
"Our results demonstrate that each type of flu vaccine offers a different kind of protection against influenza," Donna Farber, PhD, professor of surgical sciences at Columbia and the study's principal investigator, said in a statement. "Vaccine developers may want to combine these attributes in a universal vaccine that is capable of offering protection against the familiar strains of influenza we expect to see during a typical yearly outbreak as well as novel strains that can cause a pandemic."
FluMist may be particularly effective in combating pandemics, as most influenza vaccines are targeted to fight the strains researchers expect to become prevalent in the next flu season. However, some strains evolve so quickly that by the time individuals become infected, the vaccine doesn't recognize the strain it encounters. The study authors found the FluMist vaccine produced "lung-resident" immune cells, which are what helped prevent infection when exposed even to viral strains not contained in the vaccine.