Abstract: A computer-implemented method includes obtaining movement data associated with a subject and measured by a stationary motion sensor. The movement data includes a series of values representing a series of movement events of the subject crossing fields of view of the stationary motion sensor. Each movement event in the series of movement events is associated with a respective time stamp. The computer-implemented method further includes extracting a plurality of features from the movement data, determining that the movement data is consistent with symptoms of an illness using a machine-learning model and based upon the plurality of features, and generating an output indicating a result of the determination.