Methods, compositions, and systems are provided for detecting one or more effects of antibiotic usage for an infectious disease or other health condition on the microbiome of an individual, monitoring such effects, and/or determining, displaying, or promoting a therapy for such an effect. Methods, compositions, and systems are also provided for generating and comparing microbiome composition and/or functional diversity datasets. Methods, compositions, and systems are also provided for generating a characterization model for antibiotic usage.