Since 2001, Dr. Harris has focused his practice on the diagnosis and treatment of Chronic Complex Illness including Lyme disease, other tick-borne co-infections as well as myalgic encephalomyelitis, chronic fatigue syndrome (ME/CFS), fibromyalgia, autistic spectrum disorder, chronic inflammatory response syndrome (CIRS), mold & mycotoxin illness, among others. In his approach to these conditions, he incorporates strategies found in conventional, functional and complimentary medicine. He believes that there are many effective treatments available to those with chronic and persistent infections.