The flu vaccine would only pose as a risk to you if you had an allergy to certain components. Your best bet would be to chat with your doctor but some known allergens include egg proteins, including feathers, and gentamicin, an antibiotic.

There may also be some possible risks if you are pregnant or breastfeeding, although again it would be best if you speak with your doctor to discuss this.

All medicines and vaccines can have side effects. Sometimes they are serious; most of the time they are not. Some side effects may need medical treatment.

You would need to contact your doctor if you experience any of the following:

• redness, swelling, a hard lump, soreness, bruising or itching around the injection site
• fever, chills, headache, malaise (generally unwell), muscle aches and pains.

Some rare side effects include:

• swelling of limbs, face, eyes, inside of nose, mouth or throat
• shortness of breath, breathing or swallowing difficulties, hives, itching (especially of the hands or feet), reddening of skin (especially around the ears), or severe skin reactions
• unusual tiredness or weakness that is sudden and severe.

For certain indiviuals however, the possible side effects far out weigh the benefits, as influenza can be lethal to those most vulnerable. Eg. The elderly or those that suffer from a chronic disease resulting in low immunity.

I hope this answers your question.

http://www.medsafe.govt.nz/Consumers/cmi/f/Fluarix.htm

 

Flu is just like any other viral fever, but  immunosupressed people are at risk as it may cause respiratoy distress and become fatal.

There is always a risk to any immunization, however the risk is low and the does not exceed the risk of contracting the original illness. The odds are in your favor with immunizations.