How do vaccines work? Vaccines are a way of producing an immune response in the body without causing illness. Vaccines strengthen a person’s immune system by training it to recognise and fight against specific infections. Vaccines use inactivated (weakened) viruses or parts of the virus (such as a protein) to make our bodies think we have already come into contact with a particular disease. When a person is vaccinated against a disease, their immune system can quickly recognise and clear out bacteria and viruses that can cause serious illnesses from that disease.1 References Department of Health. (2021, April 9). How do COVID-19 vaccines work? Retrieved from Australian Government Department of Health: health.gov.au/initiatives-and-programs/covid-19-vaccines/learn-about-covid-19-vaccines/how-do-covid-19-vaccines-work Updated 14 July 2021