Influenza specialist Kristin Nichol, M.D., professor of medicine at the University of Minnesota Medical School, says both new flu shots may come to occupy a "special niche" in the arsenal against influenza. "It's very exciting to have these new vaccines available," she says.
As for the nasal spray flu vaccine that was first introduced in 2003, it is a weakened live vaccine recommended only for those ages 2 to 49; those 50 and older should not get it. Although an annual flu shot for older people has long been a mainstay of U.S. public health policy, the last several years have brought increasing debate among experts about just how effective the vaccine is in older people.
Research has suggested that getting the shot decreases an older person's chances of being hospitalized for flu or pneumonia, and of dying. But studies also make clear that the vaccine doesn't always protect older men and women against the flu. That's partly because the vaccine works by stimulating the body's own immune reaction — and the aging immune system tends to mount a weaker protective response.