Infectious diseases.
D017088:AIDS-Related Opportunistic Infections; D017714:Community-Acquired Infections; D003428:Cross Infection; D006801:Humans; D011014:Pneumonia / Q000175:diagnosis / Q000188:drug therapy; D012141:Respiratory Tract Infections / Q000209:etiology / Q000276:immunology / Q000382:microbiology; D014397:Tuberculosis, Pulmonary