A Neurologist's View of Lyme Disease and Other Tick-Borne Infections

John J. Halperin, MD


Semin Neurol. 2019;39(4):440-447. 

In This Article

Abstract and Introduction


Tick-borne infections—including tick-borne encephalitis viruses, represented in the United States by rare infections with Powassan and deer tick viruses, and more often Lyme disease—are of increasing importance to neurologists. Lyme neuroborreliosis (LNB) causes all or part of a triad including meningitis, radiculoneuritis, and cranial neuritis. Rarely, parenchymal brain and spinal cord involvement occur, with focal findings on examination and magnetic resonance imaging (MRI). LNB diagnosis requires plausible exposure, objective evidence of nervous system involvement, and, generally, positive two-tier serology. Central nervous system (CNS) LNB is almost always accompanied by abnormal cerebrospinal fluid (CSF) (cells, protein), often with intrathecal antibody production, which is determined by concentration-adjusted comparison of serum and CSF antibody. Measuring CSF antibody in isolation and nucleic acid-based testing of CSF are not useful in LNB and should be avoided. LNB treatment is highly effective with a 2- to 3-week course of antibiotics. Increasing evidence suggests that LNB not involving the CNS parenchyma can be treated successfully with oral doxycycline.


Despite the crucial importance of vector-borne infections in European history (Black Death) and continued prevalence and attendant mortality in much of the world (malaria), these have received relatively little attention in the United States, with one notable exception being Lyme disease. Even recent concerns about West Nile and Zika Virus pale in comparison to the public controversy concerning this infection. First characterized as an uncommon and geographically localized cause of a disorder resembling juvenile rheumatoid arthritis, this multisystem spirochetal infection has seized the public's imagination in ways few could have foreseen and serves as a lightning rod in a battle between evidence-based medicine on the one hand and internet-promoted theories based on anecdotes and medical misconceptions on the other. More recently, attention has shifted to other putative tick-borne coinfections and their potential roles in highly prevalent but otherwise medically unexplained symptoms. At the core of this debate lie several fundamental misunderstandings—among both patients and some practitioners—about the nature of neurologic disease in general and nervous system infections in particular. This article will attempt to provide both context and a rational construct to address these issues.