Facts are always helpful.......... sorry for the copy and paste but it's better to get medical information from the source.
http://www.cdc.gov/flu/about/qa/flushot.htm
What are the risks from getting a flu shot?
You cannot get the flu from a flu shot. The risk of a flu shot causing serious harm or death is extremely small. However, a vaccine, like any medicine, may rarely cause serious problems, such as severe allergic reactions. Almost all people who get influenza vaccine have no serious problems from it.
Can severe problems occur?
Life-threatening allergic reactions are very rare. Signs of serious allergic reaction can include breathing problems, hoarseness or wheezing, hives, paleness, weakness, a fast heartbeat, or dizziness. If they do occur, it is within a few minutes to a few hours after the shot. These reactions are more likely to occur among persons with a severe allergy to eggs, because the viruses used in most influenza vaccines are grown in hens’ eggs. While severe reactions are uncommon, you should let your doctor, nurse, clinic, or pharmacist know if you have a history of allergy or severe reaction to flu vaccine or any part of flu vaccine, including eggs.
There is a small possibility that influenza vaccine could be associated with Guillain-Barré syndrome, no more than 1 or 2 cases per million people vaccinated. This is much lower than the risk of severe complications from flu, which can be prevented by flu vaccine.
The Demand for Flu Vaccines. Vaccination is one of the most beneficial and cost-effective health interventions. An estimated 65 million Americans catch the flu annually, resulting in 30 million physician visits. The U.S. Centers for Disease Control and Prevention (CDC) estimates the influenza virus contributes to the death of around 36,000 U.S. residents each year, and accounts for more than 200,000 hospitalizations. Yet, the past few years (2004)have found us without enough vaccine to serve all the population vulnerable to the worst affects of the disease: the elderly, the young and those with chronic medical problems.
The Supply of Flu Vaccines. Nearly 40 years ago, there were about 26 makers of all types of vaccines. [See the figure.] The number fell to 17 by 1980. Now, the number of vaccine makers supplying the United States has dropped to only four. There is only a single manufacturer of the vaccines for eight diseases. There are only two major makers of flu vaccines. When there are so few producers of each vaccine, problems at a single plant can create shortages.
there is only about a three-month window of opportunity for producers to sell their flu vaccines for the entire year. Once a flu season has passed, remaining stockpiles are worthless. Last year one of the U.S. companies that manufacturers flu vaccine, Aventis Pasteur, had to discard 5 million of the 43 million doses it produced. Two years ago, 12 million doses of flu vaccine went unused.