An epidemiologist is a public health professional who studies the patterns, causes, and effects of health and disease conditions in populations. They collect and analyze data to understand how diseases spread and to identify risk factors. Their work helps inform public health policies and strategies to prevent outbreaks and improve community health. Epidemiologists often collaborate with other health professionals, such as public health officials, biostatisticians, and medical researchers. They may work in various settings, including government agencies, hospitals, and academic institutions, contributing to the overall understanding of health issues and guiding interventions to protect public health.