What should you know about flu shots available?

A flu vaccination presents the immune system with selected influenza material so it can build a response. Inactivated vaccines use virus material that has been treated so it cannot multiply. Protection is not a promise that every respiratory illness will be prevented, because coughs and colds can have other causes.

The formulation offered can vary with the season and a person's age or health. Tell the vaccinator about previous serious vaccine reactions, a current illness, pregnancy, or conditions affecting immunity so they can advise you safely.

Ask a licensed clinic or pharmacy which influenza vaccine is currently available and whether it is suitable for you. Wear clothing that allows easy access to the upper arm, eat and drink normally if you have no medical reason to do otherwise, and remain briefly after vaccination if the clinic recommends observation.

A sore arm, mild tiredness, or a low fever can occur after vaccination and usually settles without special treatment. Follow the clinician's advice about simple comfort measures and keep a record of the vaccination.

Seek urgent medical help for trouble breathing, swelling of the face or throat, widespread hives, fainting, or rapidly worsening symptoms after a shot. Contact a clinician for a persistent high fever, severe weakness, or symptoms that concern you, especially if you are pregnant or have a long-term condition.

Ask which vaccine is appropriate for your age and health, whether you should delay vaccination because of a current illness, and what symptoms after the injection should prompt a call.