RecruitingClinical trialLong-Term Study of COVID-19 Infection and Long COVIDThis study will examine how common Long COVID is and how symptoms may persist over time in people who have previously had COVID-19. Researchers will collect information about participants' health and symptoms through questionnaires and may collect saliva and other non-invasive oral samples. The study will also examine biological factors in these samples that may be associated with persistent symptoms. The goal is to better understand why some people develop Long COVID and identify factors that may help predict who is more likely to experience persistent symptoms.