Surveillance of Congenital Heart Defects Among Children, Adolescents and Adults (Component A) - The purpose of the proposed project is to develop population-based surveillance of 0-64-year-olds with congenital heart defects (CHDs) living in New York State with one or more healthcare encounters between 2021-2023 to examine descriptive epidemiology, age-specific mortality, healthcare utilization, and respiratory illnesses and immunizations, overall and with respect to race, ethnicity and socioeconomic status. The New York State Department of Health (NYSDOH) plans to build on its existing CHD surveillance framework comprised of records from clinics, hospital inpatient and outpatient data, Medicaid data, Birth Defects Registry data and New York State and New York City Vital Records by adding new data sources (National Death Index, New York State Immunization Information System, New York Citywide Immunization Registry). We plan to geocode residential address information to link to census data to collect census tract-level demographic and socioeconomic status indicators. We also intend to validate 200-300 cases to aid in the development of an appropriate machine learning algorithm. NYSDOH expects to achieve the following outcomes by the end of the project period: • Improved knowledge about the characteristics of individuals with CHD identified from multiple data sources • Improved understanding of: o age-specific mortality in individuals with CHD o healthcare use, comorbidities, and outcomes of individuals with CHD o health equity among individuals with CHD o racial, ethnic, and socioeconomic patterns in healthcare use and long-term outcomes in individuals with CHD o Respiratory viruses (including COVID-19, influenza, and RSV) and immunizations among individuals with CHD o healthcare use during the COVID-19 pandemic among individuals with CHD o the potential impact of state and national healthcare policies on individuals with CHD • Increased awareness among stakeholders of nationwide CHD issues