Telehealth is the use of electronic information and telecommunication technologies to provide care when the patient and the provider are not in the same room at the same time. Telehealth accounted for less than 1% of all Medicare Fee-for-Service outpatient visits in the United States in 2019 but grew to account for 46% of all visits in April 2020. Changes in reimbursement and licensure policies during the COVID-19 pandemic appeared to greatly facilitate this increased use. Telehealth will continue to account for a substantial portion of care provided in the United States and globally. A better understanding of telehealth approaches and their evidence base by public health practitioners may help improve their ability to collaborate with health care organizations to improve population health. The article summarizes the Centers for Disease Control and Prevention's (CDC's) approach to understanding the evidence base for telehealth in public health practice, possible applications for telehealth in public health practice, and CDC's use of telehealth to improve population health.

Early in the coronavirus disease 2019 (COVID-19) pandemic, in-person ambulatory health care visits declined by 60% across the United States, while telehealth* visits increased, accounting for up to 30% of total care provided in some locations (1,2). In March 2020, the Centers for Medicare & Medicaid Services (CMS) released updated regulations and guidance changing telehealth provisions during the COVID-19 Public Health Emergency, including the elimination of geographic barriers and enhanced reimbursement for telehealth services(†) (3-6). The Health Resources and Services Administration (HRSA) administers a voluntary weekly Health Center COVID-19 Survey(§) to track health centers' COVID-19 testing capacity and the impact of COVID-19 on operations, patients, and staff. CDC and HRSA analyzed data from the weekly COVID-19 survey completed by 1,009 HRSA-funded health centers (health centers(¶)) for the week of July 11-17, 2020, to describe telehealth service use in the United States by U.S. Census region,** urbanicity,(††) staffing capacity, change in visit volume, and personal protective equipment (PPE) supply. Among the 1,009 health center respondents, 963 (95.4%) reported providing telehealth services. Health centers in urban areas were more likely to provide >30% of health care visits virtually (i.e., via telehealth) than were health centers in rural areas. Telehealth is a promising approach to promoting access to care and can facilitate public health mitigation strategies and help prevent transmission of SARS-CoV-2 and other respiratory illnesses, while supporting continuity of care. Although CMS's change of its telehealth provisions enabled health centers to expand telehealth by aligning guidance and leveraging federal resources, sustaining expanded use of telehealth services might require additional policies and resources.