The COVID-19 pandemic has resulted in a concomitant deluge of medical, biological, and epidemiologic research. Clinicians are rightly interested in incorporating the best new evidence-based practices when treating COVID-19 patients and instituting SARS-CoV-2 transmission prevention protocols. However, without sufficient background knowledge, evaluating epidemiologic studies can be challenging, and a failure to identify sources of bias could lead to poor treatment decisions. Here, we provide a brief primer on key concepts and terms related to COVID-19 epidemiology in the hopes that this information will help provide clinicians with a starting point for evaluating the emerging COVID-19 literature. The SARS-CoV-2 virus has infected millions of people globally; there are over 2 million thousand reported deaths and almost 95 million confirmed cases of COVID-19 worldwide from January 2020 to 20211 . The pandemic has also spurred a huge scientific effort to understand the biology, epidemiology, and clinical treatment of the virus. Epidemiology is the study of distribution and determinants of disease states in human populations, and many epidemiological studies of SARS-CoV-2 have emerged which have contributed to a better understanding of the disease. Moreover, these epidemiological findings can inform clinical practice to improve patient outcomes. Yet, many clinicians may be unfamiliar with the basic epidemiology concepts needed to read, evaluate, and incorporate evidence-based medicine into their clinical practice, particularly as they apply to emerging infectious diseases. In this review, we aim to elucidate common epidemiological concepts essential to understanding the COVID-19 literature, with a particular focus for clinicians. Essential epidemiological concepts will be discussed, such as the terms to define morbidity and mortality, disease progression in infected individuals, and disease transmission between individuals. We will also explore basic infectious disease modeling terms. Submit manuscript via https://www.scholarscentral.org/submissions/epidemiology-open-access.html or email us at submissions@omicsonline.com Regards Grace Managing Editor Epidemiology: Open Access