title: Amblyomma americanum: a potential vector of human ehrlichiosis.
abstract: Polymerase chain reaction primers specific for Ehrlichia chaffeensis were used to amplify DNA from extracts of pooled ticks. Amplification was performed on extracts from 140 pools (1,579 total ticks) consisting of three tick genera collected from five states. The characteristic 389-basepair product was observed after amplification of extracts from seven different pools of adult Amblyomma americanum (117 pools, 1,462 ticks), but not from pools of nymphs. No specific product was observed after amplification of 20 pools (105 ticks) of Dermacentor variabilis and three pools of Ixodes scapularis (12 ticks). Ehrlichia chaffeensis was present in A. americanum at a minimum frequency of > or = 0.48%, suggesting that A. americanum may be a vector of human ehrlichiosis.
authors.affiliation: Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: B E
authors.initials: BE
authors.lastname: Anderson
authors.forename: K G
authors.initials: KG
authors.lastname: Sims
authors.forename: J G
authors.initials: JG
authors.lastname: Olson
authors.forename: J E
authors.initials: JE
authors.lastname: Childs
authors.forename: J F
authors.initials: JF
authors.lastname: Piesman
authors.forename: C M
authors.initials: CM
authors.lastname: Happ
authors.forename: G O
authors.initials: GO
authors.lastname: Maupin
authors.forename: B J
authors.initials: BJ
authors.lastname: Johnson
mesh_terms: D000818:Animals; D001096:Arachnid Vectors / Q000382:microbiology*; D001482:Base Composition; D004279:DNA, Viral / Q000032:analysis; D004536:Ehrlichia / Q000235:genetics / Q000302:isolation & purification*; D016873:Ehrlichiosis / Q000453:epidemiology / Q000635:transmission*; D004587:Electrophoresis, Agar Gel; D006801:Humans; D009693:Nucleic Acid Hybridization; D009758:Nymph / Q000382:microbiology; D016133:Polymerase Chain Reaction; D013987:Ticks / Q000382:microbiology*; D014481:United States / Q000453:epidemiology
chemical_list: D004279:DNA, Viral