While the flu vaccine is very safe for otherwise healthy individuals, some groups of people are at higher risk of complications than the rest of the population. The following is a list of people who should not get a flu shot or should talk with a doctor before getting a flu shot: - Anyone who has severe or life-threatening allergies to any ingredient in the vaccine, such as antibiotics, eggs, gelatin, or mercury - Infants under the age of six months - Individuals who have been diagnosed with Guillain-Barré syndrome (GBS) - Those who are experiencing a severe illness or infection As for individuals who are immune deficient, it is generally recommended that they and their family members receive an inactivated version of the vaccine instead of a live version of the vaccine. The CDC also recommends that pregnant women receive the flu vaccine as long as they are not at particular risk of complication, as it is safe and will help protect both the mother and the baby from influenza.