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Five persons contracted tick-borne relapsing fever after staying in a cabin in western Montana. Borrelia hermsii was isolated from the blood of two patients, and Ornithodoros hermsi ticks were collected from the cabin, the first demonstration of this bacterium and tick in Montana. Relapsing fever should be considered when patients who reside or have vacationed in western Montana exhibit a recurring febrile illness.
The author reports on a survey carried out by him in 1954 on relapsing fever in Jordan. In that country the disease is largely tick-borne, the main vector being Ornithodoros tholozani. Some of the frequent cases in the town of Nablus and the village of Marda in West Jordan may, however, be caused by O. coniceps. The centres of infection are some of the numerous caves scattered throughout the hilly areas and certain houses in which chickens are kept.It is believed that the vector ticks could be successfully exterminated by the use of insecticides and by the adoption of certain procedures outlined by the author.Arsenobenzol compounds and penicillin have been shown not to be very effective for the treatment of relapsing fever, but good results have been obtained with Aureomycin and Terramycin.
It has been demonstrated that Borrelia hermsii, a causative agent of relapsing fever, produces a factor H (FH) and FH-like protein 1 (FHL-1) binding protein. The binding protein has been designated FhbA. To determine if FH/FHL-1 binding is widespread among B. hermsii isolates, a diverse panel of strains was tested for the FH/FHL-1 binding phenotype and FhbA production. Most isolates (23/24) produced FhbA and bound FH/FHL-1. Potential variation in FhbA among isolates was analyzed by DNA sequence analyses. Two genetically distinct FhbA types, designated fhbA1 and fhbA2, were delineated, and type-specific PCR primers were generated to allow for rapid differentiation. Pulsed-field gel electrophoresis and hybridization analyses demonstrated that all isolates that possess the gene carry it on a 200-kb linear plasmid (lp200), whereas isolates that lack the gene lack lp200 and instead carry an lp170. To determine if FhbA is antigenic during infection and to assess the specificity of the response, recombinant FhbA1 (rFhbA1) and rFhbA2 were screened with serum from infected mice and humans. FhbA was found to be expressed and antigenic and to elicit a potentially type-specific FhbA response. To localize the epitopes of FhbA1 and FhbA2, truncations were generated and screened with infection serum. The epitopes were determined to be conformationally defined. Collectively, these analyses indicate that FH/FHL-1 binding is a widespread virulence mechanism for B. hermsii and provide insight into the genetic and antigenic structure of FhbA. The data also have potential implications for understanding the epidemiology of relapsing fever in North America and can be applied to the future development of species-specific diagnostic tools.
Several species of the genus Borrelia exhibit antigenic variation of variable major proteins on their surface during relapsing fever. We have investigated the African relapsing fever species Borrelia crocidurae during infections in mice and compared it with the thoroughly studied North American species Borrelia hermsii. A major difference between the two species is that B. crocidurae can bind and become completely covered with erythrocytes. In addition, B. crocidurae causes a prolonged spirochetemia which coincides with a delayed appearance of antiborrelial antibodies. We show that the antibody response against an unrelated antigen is not delayed and that antibiotic treatment, which dissociates rosettes and inhibits the spirochetes, also leads to an early antibody response. Taken together, the erythrocyte aggregation and prolonged spirochetemia hint at a new mode of immune evasion where erythrocyte-covered spirochetes may avoid contact with the phagocytic cells and B cells of the immune system, thereby delaying the onset of a specific immune response.
Serological response to louse-borne relapsing fever in Ethiopia was determined by immobilization tests using Borrelia recurrentis cultures. Isolates from 26 patients tested with autologous convalescent sera showed from 90 to 100% of the organisms had been immobilized. Sera from thirteen patients were tested with autologous and heterologous strains. Several reacted with the majority and two showed high titers against all strains tested. Screening of day 2 and day 8 sera frequently showed heterologous antibody present before autologous antibody appeared, suggesting multiple antigenic challenge to infected patients. Some strains appeared to be antigenically related, but because of the wide diversity of serological responses, no definite serological groupings could be ascertained.
Patients with Borrelia-caused relapsing fever produce cross-reacting antibodies to Borrelia burgdorferi, the anti-genetically related causative agent of Lyme borreliosis. The antibody response of the serum of a patient (acute and convalescent) with relapsing fever was analysed by the immunoblot technique using Borrelia hermsii and B. burgdorferi as antigens. The diagnosis was established by microscopic detection of spirochetes in the patient's blood. The patient's serum showed significantly elevated titers of IgG and IgM in a B. burgdorferi indirect immunofluorescence assay. Immunoblot analysis indicated the presence of cross-reacting antibodies directed to B. burgdorferi antigens with apparent molecular weights of 60, 41, 40, 36, 30 and 20 kDa.
We investigated whether host-seeking nymphs and adults of the western blacklegged tick, Ixodes pacificus Cooley & Kohls, the primary vector of Lyme disease spirochetes in far-western North America, are infected naturally with relapsing-fever group spirochetes in Mendocino County, California. Relapsing-fever group borreliae were detected in four (1.7%) of 234 nymphal and two (0.7%) of 282 adult host-seeking I. pacificus ticks by polymerase chain reaction and sequence analysis of the 16S rRNA and flagellin genes, respectively, exhibiting 99 and 98.5% sequence homology to Borrelia miyamotoi Fukunaga. Phylogenetic analysis based on these two genes revealed that the borreliae detected in these ticks belong to the relapsing-fever group and that these are closely related to, if not identical with, B. miyamotoi.
An outbreak of louse-borne relapsing fever, caused by the return to their original recruitment areas of soldiers at the end of 30 years of fighting in northern Ethiopia, was reported in the Arsi region. We studied 103 infants and children with louse-borne relapsing fever who were admitted to Asella Hospital between 1 May 1991 and 30 April 1992. Twenty-one per cent of the patients had a clear history of contact with sick ex-soldiers; 42% were students admitted to the hospital following the re-opening of schools after the summer vacation. The common clinical features of the disease were fever in 100%, headache in 84.5%, chills in 74%, abdominal pain in 51%, epistaxis in 20%, hepatomegaly in 26%, splenomegaly in 14%, petechial rash in 34% and jaundice in 10%. Differences in symptoms and signs according to age are described. Observed complications were pneumonia in 14% and central nervous system involvement in 10%. Four children went into deep coma, and two of them died. Severe disease was associated with a high density of spirochaetes in blood smears. Patients were treated with two low doses of penicillin or one dose of penicillin followed by, according to age, chloramphenicol or tetracycline, and with intravenous fluids. The case fatality rate was 1.9%. Jarisch-Herxheimer reactions occurred in 61% of patients. There were relapses in 2.9% of treated patients.
PURPOSE: To describe a case of uveitis that is associated with Borrelia hermsii relapsing fever. DESIGN: Interventional case report. METHODS: A 12-year-old boy with two weeks of relapsing fevers 10 days after camping in remote eastern Oregon was examined. Borrelia hermsii immunoglobulin M and G levels were markedly elevated. Intravenous ceftriaxone, followed by four weeks of oral cephuroxime was administered, but the patient developed unilateral floaters and blurred vision in association with anterior and intermediate uveitis. RESULTS: Doxycycline was administered for presumed residual infection. Four weeks later, the visual acuity had improved. The anterior chamber was quiet, and topical corticosteroid was tapered successfully. CONCLUSION: Although rare, Borrelia hermsii should be included in the list of spirochetal diseases that are associated with uveitis.
The Jarisch-Herxheimer Reaction (J-HR) is a clinical syndrome occurring soon after the first adequate dose of an antimicrobial drug to treat infectious diseases such as Lyme disease, syphilis, and relapsing fever. Previous attempts to identify factors mediating this reaction, that may cause death, have been unsuccessful. We conducted a prospective trial in Addis Ababa, Ethiopia on 17 patients treated with penicillin for proven louse-borne relapsing fever due to Borrelia recurrentis to evaluate the association of symptoms with plasma levels of tumor necrosis factor (TNF), interleukins 6, and 8 (IL-6 and -8). 14 of the 17 (82%) patients experienced a typical J-HR consisting of rigors, a rise in body temperature (1.06 +/- 0.2 degrees C) peaking at 2 h, leukopenia (7.4 +/- 0.6 x 10(-3) cells/mm3) at 4 h, a slight decrease, and then rise of mean arterial blood pressure. Spirochetes were cleared from blood in 5 +/- 1 h after penicillin. There were no fatalities, but constitutional symptoms were severe during J-HR. Plasma TNF, IL-6, and -8 were raised in several patients on admission, but a seven-, six-, and fourfold elevation of these plasma cytokine concentrations over admission levels was detected, respectively, occurring in transient form coincidental with observed pathophysiological changes of J-HR. Elevated plasma cytokine levels were not detected in the three patients who did not suffer J-HR. We conclude that the severe pathophysiological changes characterizing the J-HR occurring on penicillin treatment of louse-borne relapsing fever are closely associated with transient elevation of plasma TNF, IL-6, and -8 concentrations.
Pathogenic spirochetes in the genus Borrelia are transmitted primarily by two families of ticks. The Lyme disease spirochete, Borrelia burgdorferi, is transmitted by the slow-feeding ixodid tick Ixodes scapularis, whereas the relapsing fever spirochete, B. hermsii, is transmitted by Ornithodoros hermsi, a fast-feeding argasid tick. Lyme disease spirochetes are generally restricted to the midgut in unfed I. scapularis. When nymphal ticks feed, the bacteria pass through the hemocoel to the salivary glands and are transmitted to a new host in the saliva after 2 days. Relapsing fever spirochetes infect the midgut in unfed O. hermsi but persist in other sites including the salivary glands. Thus, relapsing fever spirochetes are efficiently transmitted in saliva by these fast-feeding ticks within minutes of their attachment to a mammalian host. We describe how B. burgdorferi and B. hermsii change their outer surface during their alternating infections in ticks and mammals, which in turn suggests biological functions for a few surface-exposed lipoproteins.
Louse-borne relapsing fever seems to have become endemic in the southern Sudan. The epidemic history of the disease in the Sudan is reviewed. We have studied 363 Sudanese patients involved in an outbreak of louse-borne relapsing fever in Khartoum (Sudan) between January and June 1974. 318 of the 363 patients were new immigrants from the soughern Sudan to Khartoum. The clinical presentation varied. The common clinical fetures of the disease were: fever (94%), headache (85%), hepatosplenomegaly (74%), body and joint pains (66%), abdominal pain and tenderness (63%), jaundice (46%) and epistaxis (40%). Thrombocytopenia was common. Biochemical evidence of hepatocellular and renal damage was present in most patients. The mortality rate was 5-5% with treatment. Post-mortem examination was performed on six cases. The organs predominantly involved were the liver, spleen, brain and lungs. The common causes of death were severe hepatic damage, lobar pneumonia, subarachnoid haemorrhage and splenic rupture.
We evaluated the epidemiology of relapsing fever from 1971 to 2003 in Israel. In civilians, incidence declined from 0.35 to 0.11 cases per 100,000 persons annually; in military personnel it averaged 6.4 cases per 100,000 persons annually. These data imply that the pathogen and vector continue to exist in Israel.
The quantitative buffy coat (QBC) parasite detection method is a sensitive and specific tool for the diagnosis of malaria parasites. It is also useful for the diagnoses of other hemoparasites, including Trypanosoma, Babesia, and Leptospira. We report a case of relapsing fever diagnosed by this technique in a short-term traveler from Senegal. The diagnosis was confirmed by the standard Giemsa hemoscopy and by the identification of significant titers of antibodies to Borrelia spp. of tick-borne relapsing fevers by specific immunofluorescence and Western blot tests. The QBC technique seems to be useful in the diagnosis of tick-borne relapsing fever in blood samples and should be included in the management of fever in the traveler returning from tropical regions.
The phylogenetic relationships of 20 relapsing fever (RF) Borrelia spp. were estimated on the basis of the sequences of rrs genes. Complete sequences were aligned and compared with previously published sequences, and the similarity values were found to be 97.7 to 99.9%. Phylogenetic trees were constructed by using the three neighbor-joining, maximum-parsimony, and maximum-likelihood methods. The results of the comparative phylogenetic analysis divided the RF Borrelia spp. into three major clusters. One cluster included Borrelia crocidurae, Borrelia duttonii, Borrelia recurrentis, and Borrelia hispanica. Another cluster comprised tow main branches with Borrelia coriaceae, Borrelia lonestari, and Borrelia miyamotoi on one side and Borrelia parkeri, Borrelia turicatae, and Borrelia hermsii on the other side. Borrelia anserina constituted the third cluster. The phylogenetic position of Borrelia persica was more uncertain. These results suggested that the taxonomy of these spirochetes should be revised. To overcome the problems of culturing the spirochetes, RF Borrelia primers were defined. Following PCR amplification of the rrs gene, restriction length fragment polymorphism could be used to distinguish between RF Borrelia strains.
Clinical manifestations of louse-borne relapsing fever (LBRF) in children admitted to Jimma Teaching Hospital from March 1991 to September 1991 are described. The clinical manifestations were mild and the frequency of occurrence of each feature was lower than in adults. Jaundice and cardiac abnormality have not been found in children. The Jarisch-Herxheimer reaction was also mild and occurred in about 16% of the cases. The prognosis of LBRF was excellent. Initial treatment with penicillin and continued treatment with tetracycline for a couple of days was justifiable. Further detailed studies with a larger series is recommended.
The author recalls the very fine clinical, epidemiological and experimental work undertaken since 1907 at Beni Ounif de Figuig, south of Oran near the algerian-moroccan border which led Henry Foley and Edmond Sergent to suspect and later demonstrate the exclusive role played by the louse (Pediculus corporis or more precisely P. vestimenti) in the transmission of relapsing fever of which they studied an important epidemic occurring there between 1907-1910. This discovery led them to incriminate also the louse in the transmission of exanthematic typhus of which the epidemiology is practically similar. On the occasion of a tunisian epidemic of relapsing fever Charles Nicolle resumed Sergent's and Foley's work which he contested without any justification. Trying to attribute to himself all the merit of the discovery of the role of the louse in the transmission of relapsing fever, Charles Nicolle quotes Sergent's and Foley's works contesting them with a certain bad faith. In 1912 he mentions only Sergent's and Foley's 1910 works (posterior of only one year to his confirmation of the role of the louse in the transmission of exanthematic typhus) and ignores totally their 1908 preliminary paper. One must therefore give full credit to Henry Foley associated with Edmond Sergent for this essential discovery of the role of the louse in human pathology in which they occupy the first place.
The diagnosis of louse-borne relapsing fever is commonly made on the basis of the detection of Borrelia spirochetes on Giemsa-stained thin blood films. In the present study, we used acridine orange-coated quantitative buffy coat (QBC) tubes, centrifugation, and fluorescence microscopy to detect Borrelia. Between July and August 1998, we used the QBC technique to diagnose 7 patients with borreliosis who visited a rural clinic in southwest Ethiopia. In laboratory studies that used Borrelia burgdorferi as a model, we detected spirochetes at concentrations as low as 10 organisms/mm3, whereas the number of positive readings assessed by means of stained blood films fell significantly at dilutions below 3,263 organisms/mm3. The greater sensitivity of the QBC technique is important in areas where Borrelia is endemic, as in the Horn of Africa. It may also prove useful in evaluating relapsing fevers in travelers.