Unique Strain of Borrelia miyamotoi in Ixodes pacificus Ticks, California, USA

摘要

To the Editor: Borrelia miyamotoi causes a recently recognized tickborne zoonosis in Eurasia and North America (1). The species has been detected in Ixodes persulcatus ticks in Asia and Russia, I. ricinus ticks in Europe, and I. scapularis and I. pacificus ticks in North America. In most of these regions, B. miyamotoi is sympatric with Lyme disease agents, such as B. burgdorferi, and both pathogens are transmitted locally by the same species of Ixodes ticks. B. miyamotoi generally is less prevalent than B. burgdorferi in nymphs and adults in North America (2), except in California, where the prevalences of the 2 species in populations of nymphal and adult I. pacificus ticks are similar (3–6).