The nasal spray vaccine contains a “live attenuated” flu virus, but the virus is weakened so that it cannot cause the flu. A 2013 survey conducted by the national foundation for infectious diseases revealed that 41 percent of people think the flu is only contagious after symptoms start. May persist for several weeks. : a flu headache is usually severe and tends to spread over the forehead and behind the eyes.
What kinds of flu shots are there?
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What is time line. If they are allergic to eggs or gelatin.