RGD uses the Human Disease Ontology (DO, https://disease-ontology.org/) for disease curation across species. RGD automatically downloads each new release of the ontology on a monthly basis. Some additional terms which are required for RGD's curation purposes but are not currently covered in the official version of DO have been added. As corresponding terms are added to DO, these custom terms are retired and the DO terms substituted in existing annotations and subsequently used for curation.
A primary bacterial infectious disease that results_in infection located_in skin or located_in subcutaneous tissue, has_material_basis_in Mycobacterium ulcerans, which could be transmitted_by insects. The bacterium produces a toxin, named mycolactone, which causes subcutaneous fat necrosis and inhibits an immune response. The infection has_symptom nodule, which is a painless, mobile swelling in the skin. (DO)