The emergence of coronavirus disease 2019 (COVID-19) not only poses a serious threat to the health of people worldwide but also affects the global economy. The outbreak of COVID-19 began in December 2019, at the same time as the influenza season. However, as the treatments and prognoses of COVID-19 and influenza are different, it is important to accurately differentiate these two different respiratory tract infections on the basis of their respective early-stage characteristics. We reviewed official documents and news released by the National Health Commission of the People's Republic of China, the Chinese Center for Disease Control and Prevention (China CDC), the United States CDC, and the World Health Organization (WHO), and we also searched the PubMed, Web of Science, Excerpta Medica database (Embase), China National Knowledge Infrastructure (CNKI), Wanfang, preprinted bioRxiv and medRxiv databases for documents and guidelines from earliest available date up until October 3rd, 2020. We obtained the latest information about COVID-19 and influenza and summarized and compared their biological characteristics, epidemiology, clinical manifestations, pathological mechanisms, treatments, and prognostic factors. We show that although COVID-19 and influenza are different in many ways, there are numerous similarities; thus, in addition to using nucleic acid-based polymerase chain reaction (PCR) and antibody-based approaches, clinicians and epidemiologists should distinguish between the two using their respective characteristics in early stages. We should utilize experiences from other epidemics to provide additional guidance for the treatment and prevention of COVID-19.