since it was first recognized since the 1920s ( Burgdorfer and Gage, 1986 Eisen and Eisen, 2018). scapularis, whose range had been expanding in the U.S. The isolation of its etiologic agent, Borrelia burgdorferi, from humans in 1983 ( Benach et al., 1983 Steere et al., 1983a Barbour and Benach, 2019) capped an intensive hunt for a pathogen that just a short time before had been cultured from a black legged (deer) tick ( Burgdorfer et al., 1982), initially named Ixodes dammini ( Spielman et al., 1979) but subsequently found to belong to a species, I. Lyme disease is the prototype of an emerging infectious disease ( Steere et al., 2004 Paules et al., 2018). Below we integrate current knowledge regarding the ecologic, epidemiologic, microbiologic, and immunologic facets of Lyme disease into a conceptual framework that sheds light on the disorder that healthcare providers encounter. A small percentage (~10%) of patients may go on to develop a poorly defined fibromyalgia-like illness, post-treatment Lyme disease (PTLD) unresponsive to prolonged antimicrobial therapy. However, in untreated patients, the disease may present with a wide range of clinical manifestations, most commonly involving the central nervous system, joints, or heart. If treated appropriately and early, the prognosis is excellent.
The deposition of spirochetes into human dermal tissue generates a local inflammatory response that manifests as erythema migrans (EM), the hallmark skin lesion. Tissue damage and symptomatology ( i.e., clinical manifestations) result from the inflammatory response elicited by the bacterium and its constituents. The spirochete’s unusual fragmented genome encodes a plethora of differentially expressed outer surface lipoproteins that play a seminal role in the bacterium’s ability to sustain itself within its enzootic cycle and cause disease when transmitted to its incidental human host. garinii are most associated with human disease. burgdorferi causes nearly all infections in Europe, B. burgdorferi sensu lato is transmitted by ticks from the Ixodes ricinus complex. The ailment, widespread throughout the Northern Hemisphere, continues to increase globally due to multiple environmental factors, coupled with increased incursion of humans into habitats that harbor the spirochete. Lyme disease (Lyme borreliosis) is a tick-borne, zoonosis of adults and children caused by genospecies of the Borrelia burgdorferi sensu lato complex.