New vaccine has been created using an immune adjuvant called squaline, that has been shown to produce devastating neurological injuries in animals and has been strongly linked to the Gulf War syndrome and the 200% increase in the fatal disease ALS in soldiers receiving the anthrax vaccine.
No one knows which strains of flu will be active in any given season so taking a specific vaccine is useless but the exposure to mercury can impose health hazard.
Taking regular dietary supplements to boost immune system is more sensible and effective without any potential side effects.
Possible mild side effects of the flu shot include:

Soreness, redness, and swelling at the injection site
Fainting, mainly in adolescents
Headaches
Fever
Nausea
Possible mild side effects of the nasal spray include:

Runny nose
Wheezing
Headache
Vomiting
Muscle aches
Fever
Mild side effects usually begin soon after you get the shot and last one to two days.

Possible serious side effects of vaccination include:

Difficulty breathing
Hoarseness
Swelling around the eyes or lips
Hives
Paleness
Weakness
Racing heart
Dizziness
Behavior changes
High fever
Serious side effects usually begin within a few minutes to a few hours after receiving the shot. If you experience any of these reactions, seek medical attention immediately.

Author's Bio: 

Dr. George Grant, Ph.D., I.M.D.
Specialist in Integrative Medicne
www.academyofwellness.com