What should you know about influenza immunisation?

After immunisation, the immune system builds a response to selected influenza strains. Protection develops over time and may change as circulating viruses change. A sore arm, mild fever, headache or tiredness can occur briefly. Serious allergic reactions are uncommon but urgent symptoms after vaccination need immediate help. Tell the vaccinator about previous reactions, current illness, pregnancy and immune conditions.

Bring a list of medicines and allergies, and mention any previous vaccine reaction. Remain at the service for the observation period they recommend. Rest, drink fluids and use a cool compress for local soreness if helpful. Continue hand hygiene and ventilation because immunisation does not cover every cause of cough or fever.

Call emergency services for trouble breathing, facial or throat swelling, widespread hives, collapse or severe dizziness after vaccination. Arrange medical advice for a high fever that is not settling, worsening illness, or symptoms of pneumonia such as breathlessness and chest pain. A mild sore arm alone usually needs simple self-care.

Ask which formulation is appropriate, when a repeat dose may be due, what to expect after the injection, and whether your medicines or allergies alter the plan.