The Advisory Committee on Immunization Practices (ACIP) voted unanimously in favor (13-0) of recommending a new flu shot that does not contain eggs, making it possible for adults with egg allergies between the ages of 18-49 to receive the flu shot.

The new vaccine is not an option for children or seniors who are often most at risk. The flu shot was made with cell technology called flublok which was first licensed by the Food and Drug Administration (FDA) in January 2013.

Flublok's safety evaluation was conducted in a study of about 2,500 people who were vaccinated with Flublok. The most commonly reported adverse events included pain at the site of injection, headache, fatigue and muscle aches, events also typical for conventional egg-based, inactivated influenza vaccines.

Compared with other approved influenza vaccines, Flublok does not use the influenza virus or chicken eggs in its manufacturing process. At this time, it is the only recombinant influenza vaccine approved for influenza.

Flublok contains three, full-length, recombinant hemagglutinin (HA) proteins to help protect against two influenza virus A strains, H1N1 and H3N2, and one influenza virus B strain.

According to the Centers for Disease Control and Prevention (CDC), the Advisory Committee on Immunization Practices (ACIP) is a group of medical and public health experts that develops recommendations on how to use vaccines to control diseases in the United States.

"The old guidance was that if a person's allergic reaction to eggs was only to have hives, they could get an inactivated influenza vaccine and then be observed for 30 minutes to make sure they had no reaction. Now, in addition to that option, they can get Flublok," Dr. Grohskopf told Medscape Medical News.