Rapid diagnosis and isolation of COVID-19 cases, along with identification and quarantine of their close contacts is essential if we are to control COVID-19 in the community. Currently, to diagnose someone with COVID-19, a swab is collected from the throat and deep within the nose. Swabbing is uncomfortable and healthcare workers collecting the swab must use appropriate personal protective equipment (PPE). Using saliva to diagnose COVID-19 would make it easier to test people across a wide range of settings. This study aims to find out whether testing saliva for SARS-CoV-2 is as reliable as nose and throat swabs in a range of settings, including primary care, among children, and outbreak settings.