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Serologic Evidence for Borrelia hermsii Infection in Rodents on Federally Owned Recreational Areas in California.

Vector Borne Zoonotic Dis. 2013 Mar 14. [Epub ahead of print]



1 Infectious Diseases Branch, Division of Communicable Disease Control, California Department of Public Health , Sacramento, California.


Abstract Tick-borne relapsing fever (TBRF) is endemic in mountainous regions of the western United States. In California, the principal agent is the spirochete Borrelia hermsii, which is transmitted by the argasid tick Ornithodoros hermsi. Humans are at risk of TBRF when infected ticks leave an abandoned rodent nest in quest of a blood meal. Rodents are the primary vertebrate hosts for B. hermsii. Sciurid rodents were collected from 23 sites in California between August, 2006, and September, 2008, and tested for serum antibodies to B. hermsii by immunoblot using a whole-cell sonicate and a specific antigen, glycerophosphodiester phosphodiesterase (GlpQ). Antibodies were detected in 20% of rodents; seroprevalence was highest (36%) in chipmunks (Tamias spp). Seroprevalence in chipmunks was highest in the Sierra Nevada (41%) and Mono (43%) ecoregions and between 1900 and 2300 meters elevation (43%). The serological studies described here are effective in implicating the primary vertebrate hosts involved in the maintenance of the ticks and spirochetes in regions endemic for TBRF.

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  1. I contacted the California Department of Public Health (CDPH) regarding their research and summations in their reports, specifically the Borrelia hermsii bacteria (tick-borne relapsing fever/TBRF). I was asking them for more technical data, plus concern over lack of studies for this particular organism. I had personal knowledge of contraction (myself, my daughter, and two of my sisters, plus others I knew that had undergone treatment for same) of this organism outside of the regions they specify, namely the coastal region. I was informed by their Senior Public Health Biologist in their Vector Borne Disease Section that:
    1. Their main concern was to provide a “prevention program to emphasize the importance of avoiding ticks and what to do if bitten by a tick”. I had been avoiding ticks all my life, knew the precautions, had never heard of a soft bodied tick, and never knew I had even been bitten until I started having chronic symptoms. That was not what I had asked for.
    2. It was stated unequivocally, that based on their knowledge of the few positive blood smears reported to the CDPH, “to date, all of these have been in areas of the Sierra Nevada above 3,000 ft elevation.” She continued with, “We have detected this agent only in….higher elevation areas of California.” Nothing was mentioned about incorporating studies with those having positive IgG’s, but lacking positive blood smears, into their study. Nor, were they willing to look beyond their predetermined higher elevation regions.

    My initial contact with CDPH mentioned that I, and my daughter, were bit in an elevation well below 3,000 ft. I mentioned, too, that my two sisters were bit in the Carmel/Monterey area of California, which is at ocean level. I would have thought with their commitment to public health, the CDPH would have at least responded to my inquiry with thoughtful questions, instead of entirely dismissing everything I had mentioned in my post. It was a very condescending response, addressing none of the issues I was questioning.

    Unless there is a positive blood smear for the B. hermsii bacteria, nobody wants to listen. They were not testing for the B. hermsii in locations other than what they feel were appropriate, 3,000+ ft elevation in the Sierra Nevada mountains. Therefore, the testing that could have been performed at all of the parks on the ticks gathered, was deliberately ignored, throwing away a valuable opportunity. There would have been evidence to refute their allegations if they had chosen to perform thorough testing for all the organisms at all the sites.

    As one that has contracted the Borrelia hermsii bacteria and TBRF, and knowing many others that have had the disease, I feel compelled to spread the word about this horrible disease. This has helped others to seek medical attention for previously undiagnosed symptoms (of tick borne diseases) because of a lack of understanding in the medical community to the prevalence of tick borne diseases and their symptoms. The information that is currently available through the established government sites (and medical community) fail to recognize all of the actual facts and significance of this disease, nor are they looking to rectify this situation by more thorough study, including speaking to those that actually have (or had) the disease, regardless of an actual blood smear diagnosis. My contact with the CDPH was in May of this year.

    I find that the best sites for accurate (all inclusive) information are those established by victims of this disease, where they can explain all the nuances of contracting the disease, symptoms, living with the symptoms, etc. If I had to rely solely on the information provided by the “official” sites, I would think I was making everything up….but I have lived it…so have my sisters, my daughter, other “members” of the Borrelia hermsii patient community. The common threads are among those in this community, not the government sites. Of course, my personal knowledge of this disease, gives me a more accurate basis from which to speak to others about the disease, plus where it is more accurately found.

    The “official” organizations need to have a sincerely open mind, more thorough (less prejudiced) research, more thoughtful consideration of questions posed by the public (with or without having had TBRF), inclusion of actual patients with TBRF, etc, to provide an accurate accounting of what TBRF is all about.

    The endemic regions for the soft-bodied ticks harboring the Borrelia hermsii spirochetes is significantly larger and diverse than is acknowledged by the reports of the CDPH. The San Joaquin Valley floor along its riverbeds harbors ticks carrying this spirochete. The coastal areas of California harbor these bacteria ridden ticks, as well. Positive proof can be found amongst those having contracted Tick Borne Relapsing Fever while living, or visiting, known tick infested coastal areas.

    I greatly appreciate your bringing this disease to the attention of the public. I am just sorry that the government agency cited in this article is not more familiar with the disease. As it reads, the report will give the public false confidence in visiting areas that they claim are free of the Borrelia hermsii spirochete, as I know otherwise from my sisters having been bitten on the coast and contracting the disease (TBRF) there, as well as others with the disease that I know have been bitten there, as well.

    It is all about getting the information out there….it is all about everyone working together to have an accurate accounting for the reality of the Borrelia hermsii bacteria and the Tick Borne Relapsing Fever disease. Thank you for bringing attention to this disease. I had all the Lyme symptoms, but tested negative for Lyme. I did, however, test positive for the Borrelia hermsii bacteria, which is even more dangerous than Lyme disease, but not many know about it.

    I am a strong believer that anyone with any type of an outdoor lifestyle, at the very least, should be checked yearly for tick borne diseases. It is well worth starting on treatment, long before the symptoms become debilitating through lack of knowledge in the public, as well as the medical community.

  2. It is interesting that I tested positive for borrelia hermsii and live in Massachusetts, an area that is NOT endemic. I just finished treatment. This was using antibody test. I am told it could have been a false positive. I have to wonder. Being retested in a month.

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