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The Relapsing Fever Page

This is a strange one--you might not know you have it.

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Caves Reported to have Relapsing Fever Vectors

Relapsing fever ticks are known from all the caves west of Red Bud Isle in West Lake Hills, Travis County, Texas. Stay out of these caves, they aren't worth the risk. Bill Elliott and Peter Sprouse got Relapsing Fever in Little Black Hole, summer 1994.

This work is over 20 years old and some of the information regarding treatments and immunizations is out-of-date. Do not rely on it for accuracy when looking for or prescribing treatment.

Relapsing Fever

by Alicia Wisener Gale
excerpted via OCR from The TEXAS CAVER June 1976

Borrelia Recurrentis is a spirochete that causes Relapsing Fever. It is transmitted by soft ticks of the genus Ornithodoros and it has recently been found in the body louse, pediculus humanus. Ticks such as O. turicata, O. hermsi, O. parkeri, and O. talaje are the most frequent vectors and are found all over the western US. The disease may be transmitted directly through tick bite or indirectly through coxal fluid. These ticks are fairly common inhabitants of caves.

Relapsing Fever symptoms are the same whether transmitted by tick or louse. Three to ten days after transmission, the patient undergoes a febril stage (fever) in which large numbers of Spirochetes are found in the blood, and, in a fourth of those cases, in the urine as well. After approximately 4 days, the fever declines as the number of spirochetes in the blood also drop. During the next 3 to 10 days, an afebrile stage occurs during which the organism becomes less motile and assumes bizarre forms. A second febrile stage then occurs during which spirochetes reappear in the blood, but in fewer numbers. There may be from 3 to 10 recurring febrile attacks which means a disease lasting from as few as 21 days to as many as 140 days (5 months). In fatal cases, Borrelia recurrentis may be found in the spleen and liver; with hemorrhagic lesions in the gastrointestinal tract and kidney.

Diagnosis of the disease depends on isolation of the spirochete from the blood either by darkfield microscopy, common microscopy, or animal inoculation, or Agglutination Reactions with Proteus OXK agglutimins. B. recurrentis is a flexible spiral organism from 8 to 30 microns in length with 5 to 10 loosely wound spirals. The spirochete is a motile one that stains well with Wrights, Giemsa, and other stains containing aniline dyes. Under the electron microscope, a central axial filament surrounded by a protoplasm sheath can be seen. Fibrils resembling flagella appear to arise from this axial filament. Division is believed to be by transverse fission. B. recurrentis grows well on chick embryo, but cultivation on artificial media is usually not successful. The organism is a very viable one and remain virulent for many months at refrigerator and even dry ice temperatures.

There is no immunization against relapsing fever at at the present. Some recovered patients resist disease 2 to 5 years later, while others remain resistant only so long as B. recurrens remained in the tissues. Serum agglutinins and antibodies can be demonstrated during the course of the disease and it is possible to follow the febrile and afebrile phases through the varying reactivity of these antibodies. Besides the body's natural defense through antibodies, certain drugs have proven useful. Trivalent arsenical, particularly neoarsphenamine, were used until the advent of penicillin and tetracycline. These drugs are useful only in very large doses (i.e. 1 million units per day). The drugs of choice are chlortetracycline and oxytetracycline. Exacerbation of symptoms frequently occurs following initiation of drug therapy.