No, you cannot get flu from the flu shot or nasal spray. The Centers for Disease Control and Prevention explains that the flu shot contains a killed virus that's not infectious, and the spray is made with a weakened virus that's adapted to cold, so it can't infect the lungs where temperatures are warmer. Read more here.
Flu shots that are packaged in multidose vials have preservatives, including thimerosal, which prevents the growth of bacteria. Thimerosal contains ethylmercury, which the CDC says is cleared from the body faster than another form, methylmercury, found in certain kinds of fish. Therefore ethylmercury is less likely to cause any harm, the agency says. The CDC also says thimerosal has shown to be safe when used in vaccines; however, starting in 1999 public health agencies and manufacturers agreed to reduce or eliminate thimerosal in vaccines as precaution. This year, up to 118 million doses of the flu shot will be thimerosal-free. Read more here.
It takes about two weeks for your body to develop antibodies to flu after receiving the vaccine.
Yes; the CDC projects up to 179 million doses of the flu shot will be distributed this season in the U.S., and, as of Oct. 2, about 98.5 million doses had been distributed. Find out where you can receive the vaccine here.
Yes, the Affordable Care Act requires insurance plans to cover immunization at no cost to the consumer; however, as Slate.com points out, your insurance may not cover vaccination at any location, like walk-in pharmacies, so best to check ahead.