69 - Borreliosis

Abstract

•First Described: Lyme disease (LD) – Connecticut, United States, 1982 (Burgdorfer); tick-borne relapsing fever (TBRF) – Colorado, United States, 1915.•Cause: Spirochetal bacteria of the genus Borrelia (and Borreliella); LD – Borrelia burgdorferi sensu lato, Borrelia mayonii. TBRF – Borrelia hermsii, Borrelia turicatae, Borrelia persica, Borrelia parkeri, Borrelia miyamotoi, and others. At the time of writing, the taxonomy of Borrelia is in flux; the genus name Borreliella has been proposed for organisms other than relapsing fever borreliae.•Primary Mode of Transmission: LD – Ixodes spp. ticks; TBRF – Ornithodoros spp. ticks for most, except Ixodes spp. for B. miyamotoi.•Affected Hosts: LD – Humans and a large variety of animals; disease occurs in dogs, cats, humans, horses; TBRF – humans, dogs, cats, many reservoir and end hosts.•Geographic Distribution: LD – North America, Europe, Asia; TBRF – North America, Europe, Middle East, Asia, Africa.•Major Clinical Signs: LD – Fever, lethargy, inappetence, lameness due to oligoarthritis or polyarthritis; Lyme nephritis – vomiting, weight loss, signs of protein-losing nephropathy (PLN; thromboembolic events, effusions/edema, hypertension, eventual renal failure); TBRF – fever, lethargy, anorexia, neurologic signs, thrombocytopenia; anemia in cats.•Differential Diagnoses: Lyme arthritis – lameness due to cruciate ligament rupture, primary immune-mediated polyarthritis, septic polyarthritis, and polyarthritis secondary to infection with other pathogens such as Anaplasma spp., Ehrlichia spp., Bartonella spp., Rickettsia rickettsii, and fungal organisms. Lyme nephritis – leptospirosis, bacterial pyelonephritis, primary immune-complex glomerulonephritis, familial nephropathies, amyloidosis, and glomerulonephritis secondary to other chronic infections such as dirofilariasis, babesiosis, ehrlichiosis, hepatozoonosis, leishmaniosis, and endocarditis. TBRF – fever of unknown origin, ITP, neurologic diseases.•Human Health Significance: Dogs and cats are not a direct source of human infection but may bring unfed infected ticks into the house. Evidence of canine exposure to borreliosis is a sentinel for human exposure.