Send to:

Choose Destination
See comment in PubMed Commons below
Appl Environ Microbiol. 2009 Nov;75(22):7243-52. doi: 10.1128/AEM.01704-09. Epub 2009 Sep 25.

Population structure of the lyme borreliosis spirochete Borrelia burgdorferi in the western black-legged tick (Ixodes pacificus) in Northern California.

Author information

  • 1University of California-Berkeley, Department of Environmental Science, Policy and Management, 137 Mulford Hall #3114, Berkeley, CA 94720-3114, usa.

Erratum in

  • Appl Environ Microbiol. 2010 Jan;76(1):386.


Factors potentially contributing to the lower incidence of Lyme borreliosis (LB) in the far-western than in the northeastern United States include tick host-seeking behavior resulting in fewer human tick encounters, lower densities of Borrelia burgdorferi-infected vector ticks in peridomestic environments, and genetic variation among B. burgdorferi spirochetes to which humans are exposed. We determined the population structure of B. burgdorferi in over 200 infected nymphs of the primary bridging vector to humans, Ixodes pacificus, collected in Mendocino County, CA. This was accomplished by sequence typing the spirochete lipoprotein ospC and the 16S-23S rRNA intergenic spacer (IGS). Thirteen ospC alleles belonging to 12 genotypes were found in California, and the two most abundant, ospC genotypes H3 and E3, have not been detected in ticks in the Northeast. The most prevalent ospC and IGS biallelic profile in the population, found in about 22% of ticks, was a new B. burgdorferi strain defined by ospC genotype H3. Eight of the most common ospC genotypes in the northeastern United States, including genotypes I and K that are associated with disseminated human infections, were absent in Mendocino County nymphs. ospC H3 was associated with hardwood-dominated habitats where western gray squirrels, the reservoir host, are commonly infected with LB spirochetes. The differences in B. burgdorferi population structure in California ticks compared to the Northeast emphasize the need for a greater understanding of the genetic diversity of spirochetes infecting California LB patients.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk