Lyme Disease and the Epistemic Tensions of “Medically Unexplained Illnesses”

In the US, disagreement over the biological basis of “chronic Lyme disease” has resulted in the institutionalization of two standards of care: “mainstream” and “Lyme-literate.” For mainstream physicians, chronic Lyme disease is a “medically unexplained illness” that presents with an abundance of “symptoms” in the absence of diagnostic “signs.” For Lyme-literate physicians, and complementary and alternative medicine practitioners more generally, symptoms alone provide sufficient evidence for medical explanation. Drawing upon ethnographic research among mainstream and Lyme-literate physicians, I suggest that medically unexplained illness is not a biomedical anomaly but an intrinsic feature of biomedicine.