Embodiments of various aspects described herein are directed to methods, compositions, kits and systems for rapid determination of antibiotic susceptibility of a microbe within hours after a sample is collected. In some embodiments, the methods, compositions, kits and systems described herein can allow determination of antibiotic susceptibility of a microbe based on a small number of microbes, e.g., as few as 5-10 microbes bound to a microbe-targeting substrate described herein.