Detection of Ehrlichia risticii, the agent of Potomac horse fever, in freshwater stream snails (Pleuroceridae: Juga spp.) from northern California.
Ehrlichia DNA was identified by nested PCR in operculate snails (Pleuroceridae: Juga spp.) collected from stream water in a northern California pasture in which Potomac horse fever (PHF) is enzootic. Sequencing of PCR-amplified DNA from a suite of genes (the 16S rRNA, groESL heat shock operon, 51-kDa major antigen genes) indicated that the source organism closely resembled Ehrlichia risticii, the causative agent of PHF. The minimum percentage of Juga spp. harboring the organism in the population studied was 3.5% (2 of 57 snails). No ehrlichia DNA was found in tissues of 123 lymnaeid, physid, and planorbid snails collected at the same site. These data suggest that pleurocerid stream snails may play a role in the life cycle of E. risticii in northern California.
Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California 95616, USA.
J E
JE
Barlough
G H
GH
Reubel
J E
JE
Madigan
L K
LK
Vredevoe
P E
PE
Miller
Y
Y
Rikihisa
D000595:Amino Acid Sequence; D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D002140:California; D018833:Chaperonins / Q000235:genetics; D004275:DNA, Ribosomal / Q000032:analysis; D004536:Ehrlichia / Q000235:genetics / Q000302:isolation & purification*; D016873:Ehrlichiosis / Q000635:transmission / Q000662:veterinary; D005618:Fresh Water; D006360:Heat-Shock Proteins / Q000235:genetics; D006734:Horse Diseases / Q000382:microbiology / Q000635:transmission; D006736:Horses; D008969:Molecular Sequence Data; D009876:Operon; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012908:Snails / Q000382:microbiology*
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004275:DNA, Ribosomal; C097970:GroESL protein, Bacteria; D006360:Heat-Shock Proteins; D012336:RNA, Ribosomal, 16S; D018833:Chaperonins