Lyme Disease and Other Tick-Borne Infections

Purpose of Review The neurologic manifestations of selected tick-transmitted infections in North America and Eurasia were reviewed. Recent Findings Both Powassan virus in North America, and Tick-Borne Encephalitis (TBE) virus in Eurasia can cause encephalitis, often with significant neurologic morbidity. Lyme disease, Ehrlichia chaffeensis (the cause of human monocytic ehrlichiosis [HME]), and Borrelia miyamotoi infections can cause meningitis (the third primarily in immunocompromised individuals). Patients with Lyme disease may also develop cranial neuropathy, and/or radiculoneuropathy. Summary Tick-borne infections are being increasingly recognized in North America and Eurasia. While many tick-borne infections can cause headaches, lethargy or other non-specific symptoms, these are generally not evidence of nervous system infection – i.e., neuroinvasive disease. The latter is less common but may occur in infections due to Powassan and TBE viruses, in HME and in Lyme disease . Patients with symptomatic nervous system infection due to Powassan or TBE virus are at high risk of developing significant neurologic impairment and sequelae.