The COVID-19 vaccine that you have had has been shown to reduce the chance of you suffering from COVID-19 disease. Millions of doses of the vaccine have been given worldwide. The vaccine is highly effective in children and young people. It may take a few weeks for your body to build up some protection from the vaccine. Like all medicines, no vaccine is completely effective, so you should continue to take recommended precautions to avoid infection. Some people may still get COVID-19 despite having a vaccination, but this should be less severe.