Erythema Chronicum Migrans in America

History of the geographic distribution of the western blacklegged tick, Ixodes pacificus, in the United States

“…This study provided the first documentation of Lyme disease spirochetes from I. pacificus in California, with infected ticks collected from all three counties albeit at low prevalence of infection (0.9–1.4%). It also should be noted that Naversen and Gardner (1978) reported a case of erythema chronicum migrans from Sonoma County on the North Coast in the late 1970s (the year was not specified) associated with the bite of a tick determined to belong to the genus Ixodes , most likely I. pacificus .…”

Helical Mycoplasmas (Spiroplasmas) from Ixodes Ticks

“…The disease syndrome in the first two regions correlates with the distribution ofIxodes dammini, whereas cases in California and Oregon have occurred within the range of Ixodes pacificus (11). The latter species has been implicated in at least one case of Lyme disease in California (18). While no evidence is available to relate spiroplasmas to Lyme disease, the isolation of a new spiroplasma from Ixodes pacificus provides an opportunity to assess the vertebrate pathogenicity of spiroplasmas and the occurrence of specific antibody in the serum of man and animals.…”