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The common name for any member of the order Spirochaetales.



a bacterium, measuring 0.1–0.6 micrometer in diameter and 5–500 micrometers in length, in the form of an elongated coiled spiral. The majority of species have a slender axis filament around which the body of the cell is spirally coiled. Spirochetes lack flagella and are characterized by undulating movements, during which the cells rotate around their long axis. Reproduction is by transverse fission.

Spirochetes may be nonpathogenic or pathogenic. The former inhabit freshwaters, and the latter parasitize mollusks and cause syphilis in man (Treponema pallidum), relapsing fever (Borrelia recurrentis), and other spirochetoses. Under artificial conditions, nonpathogenic spirochetes grow on ordinary nutrient mediums and pathogenic spirochetes grow on mediums that contain serum and pieces of fresh tissue or the internal organs of animals. Some forms have not yet been grown in the laboratory.

References in periodicals archive ?
A white blood cell cannot produce antibodies if it is invaded by spirochetes or Bartonella-like organisms and struggles for its own survival.
Spirochetes were seen on peripheral blood smear (online Technical Appendix Figure 2).
We are cautious when examining these biopsies because some non-Treponema spirochetes are present in the normal microbiota of the human oropharynx and gastrointestinal tract.
Indeed, even during the pre-immune phase of infection, spirochetes populate many tissues with no evidence of inflammation (thus inflammation does not necessarily correlate with spirochete presence).
Six confirmed cases (four by visualization of spirochetes on blood smear and isolation and two by visualization of spirochetes alone) and five probable cases were identified (attack rate: 24%).
The cytotoxic effect of NO towards the spirochete indicates its significance for bacterial growth monitoring in the in vivo conditions.
In one report of a patient who developed an EM rash after traveling to Maryland and North Carolina, a novel spirochete was detected by PCR from both the patient and the tick still attached to his abdomen.
But because the spirochetes are genetically similar, the illnesses they cause respond to the same antibiotic regimen, Dr.
The risk of transmission of the spirochete (B, Burgdorferi) from the infected deer tick is directly related to how long the tick stays attached (the duration of the feeding).
Human-targeted approaches to blocking transmission of the Lyme disease spirochete include vaccines and antibiotic prophylaxis.
However, it must be noted that presence of fecal spirochetes does not coincide with symptomatology.
These results indicate that both elk and moose are susceptible to infection and may be a source of transmitting the spirochete to ticks (Kathleen et al.