Journal of Medical Entomology (1994) 31, 417-424

Robert S. Lane, Richard N. Brown, Joseph Piesman and Chindi A. Peavey (1994)
Vector competence of Ixodes pacificus and Dermacentor occidentalis (Acari: Ixodidae) for various isolates of Lyme disease spirochetes
Journal of Medical Entomology 31 (3), 417-424
Abstract: The vector competence of the western black-legged tick, Ixodes pacificus Cooley and Kohls, and the Pacific Coast tick, Dermacentor occidentalis Marx, for the Lyme disease spirochete (Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt and Brenner) was compared. Rabbits, hamsters, and the deer mouse, Peromyscus maniculatus (Wagner), were injected with cultured spirochetes or infected tick-suspensions, or were fed upon by spirochete-infected ticks. Five of seven isolates used as inocula were reisolated from vertebrates with the ear-punch biopsy technique. Three isolates (CA4, 5, 7) that were infectious for both vertebrates and ticks possessed prominent low-molecular-weight protein bands that had relative mobilities of ~24-26 kd. The ability of ticks to acquire and maintain various inocula of B. burgdorferi was evaluated by feeding uninfected larvae xenodiagnostically on all three hosts 0-63 d postinjection. Low percentages (0-10.6%) of the I. pacificus and none of the D. occidentalis became infected. By contrast, 33% of I. pacificus and 40% of Ixodes scapularis Say (= I. dammini Spielman, Clifford, Piesman and Corwin) that fed on hamsters infected by tick-bite acquired and transstadially passed spirochetes; 10% of D. occidentalis fed on infected hamsters similarly acquired but did not maintain spirochetes. Ixodes pacificus nymphs efficiently transmitted B. burgdorferi to deer mice and a hamster. Feeding by one spirochete-infected nymph was sufficient to produce patent infections in each of five mice.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Ixodes pacificus
	Dermacentor occidentalis