How the polio vaccine was developed

Poliovirus can infect the digestive system and, in some people, affect the nervous system, causing weakness or paralysis. Vaccination exposes the immune system to a safe form or component of the virus so it can build protection without causing polio. Protection helps the body respond if it later encounters the virus.

Different programmes use injectable inactivated polio vaccine, oral polio vaccine, or both, depending on local guidance. The schedule is designed to build and maintain protection during childhood. Vaccination reduces the chance of illness and transmission, but no vaccine changes the need for medical assessment when symptoms are concerning.

Check the child’s immunisation record and follow the schedule recommended by your local health service. If doses were missed, a clinic can advise on catch-up vaccination; do not restart or duplicate doses without guidance. Tell the vaccinator about serious previous reactions, immune-system conditions, or medicines that affect immunity.

Mild soreness, fever or fussiness can occur after vaccination and usually settles with simple care. Use medicines for fever only as advised for the child’s age and health. Keep the record available when travelling or changing clinics. More information is available in [Childhood Immunisation](/treatments/preventive-care-and-vaccination/childhood-immunisation/).

Seek urgent care after vaccination for breathing difficulty, facial swelling, collapse, unusual limpness or a rapidly spreading rash. Contact a clinician for a high or persistent fever, a child who is difficult to wake, or symptoms that are worsening. New limb weakness, difficulty swallowing or breathing, or loss of movement needs emergency assessment whether or not the child is vaccinated.

Ask which polio vaccine is used, which doses are recorded, whether catch-up is needed, and what to expect afterwards. Discuss travel plans, immune conditions, previous reactions and how to obtain a replacement immunisation record.