ABSTRACT The purpose of this one-year supplement is to understand the role of telehealth in public health surveillance and health outcomes in the COVID-19 pandemic. Our parent project (R01HS026506), developing and evaluating interventions to promote antibiotic stewardship in telehealth, is of both direct and indirect import. Appropriate use of antibiotics is a textbook model of promoting evidence-based practice. However, COVID-19 has put a spotlight on the need to implement a surveillance and dissemination system for emerging evidence. Concern over the safety of in-person visits and concurrent changes in policies have resulted in unprecedented uptake of telehealth in 2020. Telehealth service providers with national penetration are uniquely positioned for near real-time surveillance of public health and clinician response. In a one-month monitoring period starting March 1, 2020, over 21,546 Teladoc® patients were clinically diagnosed or deemed to have high-risk exposure to a known COVID-19 case. By incorporating outcomes from claims data and new knowledge into our existing system, we have the opportunity to rapidly update and disseminate evidence. Our analysis environment links the Teladoc® electronic medical record with continuous updates of over 1.7 million beneficiaries’ data since 2018. This linked longitudinal data set includes both telehealth and non-telehealth users. This supports analysis of outcome differences and associated changes before and after the pandemic. The first objective in this one-year supplement will advance our collaboration with the public health agencies to assess the value of this data in syndromic surveillance. Second, we will extend our antibiotic practice variation monitoring to include additional practices, including off-label prescribing and referral patterns for suspected COVID-19 patients. The third and fourth objectives will assess the feasibility of two causal inference studies using outcomes from claims, including an investigation of the impact that utilization changes have had on AHRQ Ambulatory Care Sensitive Conditions and disparities. Our work will have immediate impact on public health and service delivery, using an integrated system for developing and disseminating COVID-19 evidence in the largest and most geographically diverse telehealth provider in the US.