1. A system for determining a presence of an analyte in blood, the system comprising: at least one memory storage medium configured to store a plurality of images of a sample slide, the plurality of images including, a plurality of fields-of-view, each including a unique x and y coordinate of the sample slide; and a plurality of focal planes, each having a unique z coordinate of the sample slide; at least one processor operably coupled to the at least one memory storage medium, the at least one processor being configured to, determine and apply a white balance transform to each of the plurality of images effective to produce a plurality of color-corrected images; determine and apply an adaptive grayscale transform to each of the plurality of images to provide an adaptive grayscale intensity image for each of the plurality of images; detect and identify one or more candidate objects in the plurality of color-corrected images and the adaptive grayscale intensity images; extract and score the one or more candidate objects based at least in part on one or more characteristics of the one or more candidate objects, filter the one or more candidate objects based at least in part on the score, and output one or more color-corrected image patches and one or more adaptive grayscale intensity image patches for each filtered candidate object; extract one or more feature vectors from the color-corrected image patches and the adaptive grayscale intensity image patches and output the one or more feature vectors; classify each of the one or more feature vectors as corresponding to an artifact or an analyte; and determine if the feature vectors classified as analytes are above or below a threshold level associated with a positive diagnosis.