title: Growth kinetics of the Lyme disease spirochete (Borrelia burgdorferi) in vector ticks (Ixodes dammini).
abstract: Lyme disease spirochetes (Borrelia burgdorferi) multiplied rapidly in larval Ixodes dammini, reaching a mean density of 2,735 spirochetes/tick on day 15 post-repletion. A 5-fold drop in spirochete levels occurred during the subsequent premolting period. Recently molted nymphs contained a mean of less than 300 spirochetes/tick. Following nymphal repletion, spirochete multiplication renewed, reaching a mean abundance of 61,275 spirochetes/nymph on day 75 post-repletion. A 10-fold drop in spirochete abundance occurred again when ticks molted to the adult stage. Tick-derived spirochetes proved to be infectious when greater than 10(4) spirochetes were inoculated ip into hamsters (4 of 4 animals infected). Inocula of 10(3-4) spirochetes were not always infectious (8 of 23 animals infected), and inocula of less than 10(3) spirochetes were insufficient for establishing infection (0 of 8 animals infected).
authors.affiliation: Centers for Disease Control, Fort Collins, Colorado.
authors.forename: J
authors.initials: J
authors.lastname: Piesman
authors.forename: J R
authors.initials: JR
authors.lastname: Oliver
authors.forename: R J
authors.initials: RJ
authors.lastname: Sinsky
mesh_terms: D000818:Animals; D001096:Arachnid Vectors / Q000382:microbiology*; D025065:Borrelia burgdorferi; D015748:Borrelia burgdorferi Group / Q000254:growth & development*; D006224:Cricetinae; D005260:Female; D007700:Kinetics; D007814:Larva / Q000382:microbiology; D008193:Lyme Disease / Q000635:transmission*; D008647:Mesocricetus; D013987:Ticks / Q000382:microbiology*