PROJECT ABSTRACT In Puerto Rico (PR), the first COVID-19 case was confirmed early March 2020. To date cases have exponentially increased partly due to the lifting of locked-down restriction by the PR government, limited COVID-19 testing, and contact tracing. Puerto Ricans living on the island are particularly vulnerable to the current overlapping of the COVID-19 pandemic and natural disasters (earthquake, hurricanes/storms). Limited access to molecular COVID-19 testing throughout PR has been a significant challenge. Without adequate testing, estimates for SARS-CoV-2 (COVID-19) infection rates are limited and targeted prevention efforts (focused testing) may hinder. A group of epidemiologists led by Dr. Marzán (MPI) developed a web-based COVID-19 Epidemiologic Surveillance System (ESSS) in collaboration with the Puerto Rico Public Health Trust (PRPHT, community partner for this grant) with more than 46,000 surveys completed. The ESSS tool is an online geocoded survey that identifies real-time data of COVID-19 signs and symptoms during the last 24 hours; and thus, prioritizes communities for COVID-19 testing. Leveraging the current PHSU-PRI COVID-19 prevention efforts and the ESSS infrastructure, the research team will test the preliminary impact of an epidemic intelligence (EpI-Net) community-based intervention aimed at increasing COVID-19 testing uptake and prevention practices among socially vulnerable communities in PR. The working hypothesis is that the integration of lay community leaders, trained in the use of COVID-19 prevention technology tools (EpI-Net), will result in increased COVID-19 testing uptake and prevention practices among the targeted socially and epidemiologically vulnerable communities in Puerto Rico. This highly innovative and impactful study will shift current COVID-19 prevention strategies by 1) establishing an epidemic intelligence infrastructure using a technology-based COVID-19 syndromic surveillance (ESSS) platform to identify in real time potential COVID-19 outbreaks and, thus, conduct targeted COVID-19 testing, 2) by implementing a population-based COVID-19 prevention intervention (EpI-Net) co-led by epidemiologists and lay community leaders trained as health promotors.