Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| ecological study of rocky mountain spotted fever in costa rica. | since rocky mountain spotted fever (rmsf) was recognized in costa rica, ecological studies have been undertaken to discern its distribution and the natural cycle of rickettsia rickettsii. the population of ticks parasitizing animals and vegetation was scarce. rickettsiae were not isolated from pools of ticks nor from spleens of the animals studied. however, the active circulation of rickettsiae was evidenced through the demonstration of spotted fever group antibodies in humans, dogs, and wild ra ... | 1986 | 3080917 |
| production and characterization of cloned t-cell hybridomas that are responsive to rickettsia conorii antigens. | t-cell hybridomas produced by the fusion of rickettsia conorii immune t cells to the akr thymoma bw 5147 produced interleukin-2 when stimulated with the antigens of three different r. conorii strains. one cloned hybridoma responded only to r. conorii antigens, whereas a second and third cloned hybridoma also responded to the antigens of rickettsia rickettsii sheila smith and rickettsia sibirica 246, respectively. antigen responses required antigen-presenting cells, and this interaction was major ... | 1986 | 3082761 |
| [serologic studies of spotted fever group rickettsiosis occurring in muroto-city, kochi prefecture]. | 1986 | 3090165 | |
| widespread, simultaneous increase in the incidence of spotted fever group rickettsioses. | 1986 | 3755454 | |
| spotted fever group rickettsiae in the lone star tick, amblyomma americanum (acari: ixodidae). | 1986 | 3772952 | |
| isolation on "vero" cells of a spotted fever group rickettsia "mortilli strain" from rhipicephalus sanguineus. | the isolation of a spotted fever group (sfg) rickettsia "mortilli strain" from brown dog ticks rhipicephalus sanguineus removed from dogs associated with a confirmed case of boutonneuse fever (bf) in a site of a western sicily is reported. the need is stressed for isolation and adaption on cell cultures of sfg rickettsial strains for analysis of antigenic structure employing modern methodology. | 1986 | 3792517 |
| analysis of t-cell-dependent and -independent antigens of rickettsia conorii with monoclonal antibodies. | four monoclonal antibodies from euthymic mice and two monoclonal antibodies from athymic mice were directed against antigens of rickettsia conorii, as shown by both indirect immunofluorescence and an enzyme immunoassay. there was extensive cross-reactivity with other spotted fever group rickettsiae. euthymic monoclonal antibodies 3-2 and 9-2 (immunoglobulin g2a [igg2a]) and 27-10 (igg1) distinctly outlined the acetone-fixed rickettsial surface, as determined by indirect immunofluorescence; only ... | 1987 | 3793235 |
| barbash strain spotted fever group rickettsia is a strain of rickettsia conorii and differs from rickettsia sibirica. | the barbash strain of spotted fever group rickettsia was reexamined in this study by the microimmunofluorescence test with mouse antisera and with monoclonal antibodies. protein immunoblotting was performed for comparison of purified antigens of r. rickettsii, r. sibirica, r. conorii and barbash strain. comparison of barbash strain, r. rickettsii (sheila smith strain), r. conorii (malish 7 strain), and r. sibirica (strains 232, 246 and jinghe-74) of the spotted fever group in the microimmunofluo ... | 1987 | 2894143 |
| evidence for infection caused by spotted fever group rickettsia in kyushu, japan. | of 50 cases that gave negative immunofluorescence reaction with rickettsia tsutsugamushi among patients with suspected tsutsugamushi disease encountered in miyazaki prefecture during the last four years, three showed a significant rise in the antibody titer to rickettsia montana, a species of spotted fever group. this paper reports evidence for the occurrence of the rickettsial infection of the spotted fever group in kyushu, japan. | 1987 | 3430820 |
| antibodies to spotted fever-group rickettsiae in dogs in north carolina. | a seroepidemiologic survey was conducted to determine the prevalence of antibodies reactive with 4 spotted fever-group (sfg) rickettsiae in sera of dogs from various geographic regions in north carolina. serum specimens were obtained from 600 dogs, and antibody titers were determined, using microimmunofluorescence. data analysis (setting as the criterion for a positive result, a rickettsia rickettsii titer greater than or equal to 1:64) overestimated the actual prevalence of canine exposure to t ... | 1987 | 3118744 |
| isolation of a spotted fever group rickettsia from a patient and related ecologic investigations in xinjiang uygur autonomous region of china. | investigation of patients, healthy persons, and ticks in jinghe county, xinjiang uygur autonomous region, people's republic of china, for evidence of spotted fever group (sfg) rickettsiosis demonstrated strong evidence for a high prevalence of pathogenic sfg rickettsiae. antibodies to sfg rickettsiae were detected in 62.5% of healthy subjects tested by enzyme-linked immunosorbent assay and 20% tested by complement fixation test. two febrile patients were documented as having acute spotted fever ... | 1987 | 3571471 |
| rickettsial and serologic evidence for prevalent spotted fever rickettsiosis in inner mongolia. | a field study in northeastern inner mongolia, people's republic of china, in june of 1985 demonstrated a spotted fever group rickettsiosis. two strains of spotted fever group rickettsiae were isolated. one strain was obtained from the blood of a patient with an eschar, regional lymphadenopathy, and history of a recent tick bite. the other strain originated from ova of ticks, dermacentor nuttalli. these represent the second isolate of a spotted fever group rickettsia from a human and the first is ... | 1987 | 3578658 |
| familial cases of boutonneuse fever. | pairs of cases of boutonneuse fever (bf) occurred in three families. the illness appeared almost simultaneously in both members of each family, but was generally more serious in one as judged by clinical and laboratory parameters. the possibility of a "bed rickettsiosis", that is reactivation of rickettsiae by the blood meal obtained from the first individual by the same tick which fed upon the second individual, could be excluded in two of the three pairs of cases. in only one of the case pairs ... | 1987 | 3691750 |
| identification of spotted fever group rickettsiae from human and tick sources in the people's republic of china. | 1987 | 3305723 | |
| epidemiology and ecology of rickettsial diseases in the people's republic of china. | since 1949, information on rickettsial diseases in the people's republic of china has been virtually nonexistent in the west. this is the first comprehensive review of the ecology and epidemiology of chinese rickettsial diseases to be published outside the people's republic. at least five rickettsioses exist in china: scrub typhus, murine typhus, epidemic typhus, q fever, and one or more spotted fever-group (sfg) rickettsioses. although epidemic typhus has been controlled and scrub typhus has ab ... | 1987 | 3326129 |
| reactivity of monoclonal antibodies to rickettsia rickettsii with spotted fever and typhus group rickettsiae. | analysis of 15 spotted fever group (sfg) and 2 typhus group strains of rickettsiae with a panel of monoclonal antibodies revealed a number of shared and unique epitopes of the 120- and 155-kilodalton surface proteins. all of the sfg strains but neither of the typhus group strains reacted with antibody to the lipopolysaccharidelike antigen of rickettsia rickettsii; possibly the lipopolysaccharidelike antigen is the common antigen which defines the sfg. north carolina and montana strains of r. ric ... | 1987 | 2432081 |
| protective monoclonal antibodies recognize heat-labile epitopes on surface proteins of spotted fever group rickettsiae. | thirty-eight monoclonal antibodies that have not been reported previously were developed from mice immunized with rickettsia rickettsii, r. conorii, and r. sibirica. western immunoblotting showed that these monoclonal antibodies are directed against heat-sensitive epitopes which are located on two major surface polypeptides with molecular sizes ranging from 115 to 150 kilodaltons. the detection of the two bands did not depend on the presence of 2-mercaptoethanol. both bands were destroyed by tre ... | 1988 | 2458318 |
| antigenic analysis of chinese strains of spotted fever group rickettsiae by protein immunoblotting. | protein immunoblotting demonstrated that 6 chinese strains of spotted fever group (sfg) rickettsiae from northern china had antigenic polypeptides identical to those of rickettsia siberica (strains 246 and 232), and dissimilar to other sfg rickettsiae. the various species of other sfg rickettsiae exhibited serologically distinct epitopes as well as many cross-reactive epitopes in protein immunoblotting. all sfg rickettsiae examined in this study had major antigenic polypeptides of 113-160 kda. | 1988 | 2461661 |
| isolation of spotted fever group rickettsiae from humans in japan. | 1988 | 3411156 | |
| comparative evaluation of the indirect immunoperoxidase test for the serodiagnosis of rickettsial disease. | an indirect immunoperoxidase test was compared with an indirect fluorescent antibody test and the weil-felix oxk test for serodiagnosis of scrub typhus by measuring the rickettsial antigen specific activity of igg, igm, and whole globulin. acute and convalescent sera from 50 rickettsia tsutsugamushi isolate-positive scrub typhus patients and from 45 febrile patients diagnosed as having diseases other than scrub typhus were tested. the receiver operating characteristic for each test showed that t ... | 1988 | 3128129 |
| clinical, hematologic, and humoral immune response in female dogs inoculated with rickettsia rickettsii and rickettsia montana. | female beagles were inoculated intradermally with a sublethal dose of rickettsia rickettsii and r montana. three dogs (group 1) were inoculated with 2 x 10(2) plaque-forming units (pfu) of r rickettsia and were treated with tetracycline beginning on postinoculation day (pid) 12; 3 dogs (group 2) were inoculated with 2 x 10(2) pfu of r rickettsii but were not treated; 3 dogs (group 3) were inoculated with 2 x 10(2) pfu of r montana. group-3 dogs failed to seroconvert and were inoculated a second ... | 1988 | 3128147 |
| a focus of rocky mountain spotted fever within new york city. | in the spring and summer of 1987, four persons acquired rocky mountain spotted fever within new york city, an area in which the disease had not previously been known to be endemic. three of the four patients were residents of the soundview area of the bronx. all diagnoses were confirmed by indirect fluorescent-antibody tests. environmental investigation revealed that the tick vector for rickettsia rickettsii, dermacentor variabilis, was present in a local park. of the 66 specimens of d. variabil ... | 1988 | 3130574 |
| [rickettsiosis of spotted fever group encountered in muroto area of shikoku, japan--clinical and epidemiological features of 23 cases]. | 1988 | 3143786 | |
| antibodies to ehrlichia canis, ehrlichia platys, and spotted fever group rickettsiae in louisiana dogs. | antibodies to ehrlichia canis, ehrlichia platys, and spotted fever group (sfg) rickettsiae were detected by indirect immunofluorescence in sera from 27 ill individually owned thrombocytopenic dogs (platelet concentrations less than 200,000 platelets/microliters) and 59 healthy kenneled dogs located in southern louisiana. platelet concentrations less than 100,000 platelets/microliters were detected in 63% of ill thrombocytopenic dogs and 6.8% of healthy kennel dogs. one ill thrombocytopenic dog h ... | 1988 | 3146636 |
| [the causative agent from a patient with spotted fever group rickettsiosis in tokushima, japan]. | 1988 | 3148010 | |
| addition of monoclonal antibodies specific for rickettsia akari to the rickettsial diagnostic panel. | monoclonal antibodies were produced from mice infected with rickettsia akari (the etiologic agent of rickettsialpox) and evaluated for specificity in indirect fluorescent-antibody tests with 23 different rickettsial antigens. of the nine antibodies that were evaluated, two were specific for r. akari and four reacted with r. akari and all other spotted fever group rickettsiae. the remaining three antibodies reacted with some, but not all, members of the spotted fever group. none of the antibodies ... | 1988 | 3183012 |
| rickettsiae of the spotted fever group associated with the host-parasite system oryctolagus cuniculi/rhipicephalus pusillus. | wild rabbits--oryctolagus cuniculi--living in large numbers in a protected zone of tuscany, the park of migliarino--san rossore--massaciuccoli, showed to be carriers of the hard tick rhipicephalus pusillus, previously observed in north africa and sicily. antibodies to rickettsia conorii and r. slovaca were detected in 78.9 per cent of the wild rabbits captured in that area. seroconversion towards r. conorii was also observed in guinea pigs inoculated with homogenates of r. pusillus parasitizing ... | 1988 | 3195257 |
| rickettsiosis in japan. | the rickettsial diseases of man in japan include tsutsugamushi disease (scrub typhus), murine typhus, which occurs sporadically, and one of spotted fever group diseases, recognized as a new entity since 1984. starting from 1976, there has been a remarkable resurgence in the number of reported cases of tsutsugamushi disease in japan after several years of virtual absence, and endemics are still continuing after reaching a prominent outbreak in 1984. its yearly incidences from 1982 to 1986 were 53 ... | 1988 | 3210342 |
| ultrastructural study on japanese isolates of spotted fever group rickettsiae. | japanese isolates of spotted fever group rickettsiae were observed under a transmission electron microscope. in vero cells persistently infected with japanese isolates, small numbers of intracytoplasmic rickettsiae were seen. on the other hand, moderate numbers of rickettsiae were found in the cytoplasm of productively infected bhk cells. the electron-lucent, halo-like zone was found to surround organisms in the cytoplasm of their host cells, which is a prominent characteristic of spotted fever ... | 1988 | 3221801 |
| occurrence of rickettsiosis of spotted fever group in chiba prefecture of japan. | acute- and convalescent-phase sera were obtained from a patient with suspected tsutsugamushi disease in july 1987, in amatsukominato located in the southeastern area of chiba prefecture, and showed negative serologic reactions with rickettsia tsutsugamushi, while the convalescent-phase serum reacted positively with r. montana and a japanese isolate of spotted fever group rickettsia at igm and igg titers of 1:320 and 1:640, respectively, in the indirect immunofluorescence test. these findings sho ... | 1988 | 3241460 |
| identification of a unique spotted fever group rickettsia from humans in japan. | 1989 | 2470833 | |
| characterization of sicilian strains of spotted fever group rickettsiae by using monoclonal antibodies. | twenty-two hybridomas producing anti-rickettsia conorii monoclonal antibodies were obtained by nine fusion experiments. the strain chosen for immunization of mice was mavi, an r. conorii strain isolated from a sicilian patient with boutonneuse fever. when tested for immunoglobulin isotype by an indirect immunofluorescence (iif) assay, 46.6% of supernatants from the 22 hybridomas were immunoglobulin m. the supernatants were tested in the iif assay for binding to the mavi strain and four spotted f ... | 1989 | 2473092 |
| [differences in sensitivity of passive hemagglutination and passive hemolysis reactions in serological diagnosis of rickettsial infections]. | we compared the sensitivity of indirect hemagglutination and indirect hemolysis tests by detection of antibodies in sera of man, rabbits and sheep after infection with r. slovaca, r. sibirica and c. burnetii. we found that the titres of antibodies in indirect hemolysis are 4 times higher than in indirect hemagglutination namely with the sera of man, rabbits and sheep. this method can be recommended for diagnoses of rickettsiae of spotted fever group. | 1989 | 2485299 |
| production of antibody to and cellular localization of erythrocyte-sensitizing substance from rickettsia rickettsii. | antibodies to rickettsia rickettsii erythrocyte-sensitizing substance (ess) were raised in rabbits by using a derivatized ess. the resulting antibodies reacted with r. rickettsii and cross-reacted with rickettsia conorii, a member of the spotted fever group rickettsiae, but did not react with rickettsia typhi, a member of the typhus group rickettsiae, legionella bozemanii, or proteus vulgaris ox19 or ox2. immunoblot analysis indicated that ess was present in more than one fraction and that the m ... | 1989 | 2497137 |
| comparison of antigenic reactivity between intracellular and extracellular rickettsiae of spotted fever group. | antigens of intracellular rickettsiae in vero cells persistently infected with japanese yh strain of the spotted fever group (rickettsia japonica sp. nov.) reacted in the immunofluorescence test with sera from patients to the same extent by igg antibody titration as did antigens of extracellular rickettsiae prepared from culture fluid of lytically infected bhk cells. on the other hand, igm antibody titers measured with intracellular rickettsiae in vero cells were significantly higher in some cas ... | 1989 | 2516664 |
| mediterranean spotted fever in salamanca, spain. epidemiological study in patients and serosurvey in animals and healthy human population. | mediterranean spotted fever is a spotted fever group rickettsiosis caused by rickettsia conorii. the fever has a recognized incidence in large geographic areas, and its presence in salamanca province (spain) has been well documented since 1981. this work presents the results of the centralized prospective survey carried out in this area and was designed to study the epidemiological behavior of the disease and the prevalence of antibodies against r. conorii among animals and healthy human populat ... | 1989 | 2575869 |
| rickettsiae of the spotted fever group in dog fleas (ctenocephalides spp.) in western sicily. | 1989 | 2604471 | |
| spotted fever group rickettsia in dogs in japan. | prevalence of antibody against spotted fever group-rickettsia in dogs (14/134) from the northern part of shikoku island, where spotted fever group rickettsia infection in human is endemic, is significantly higher than that in dogs (4/189) from nonendemic areas. | 1989 | 2635227 |
| rickettsioses of the spotted fever group around the world. | spotted fever group rickettsioses comprise rocky mountain spotted fever (rickettsia rickettsii), boutonneuse fever (r. conorii), north asian tick typhus (r. sibirica), queensland tick typhus (r. australis), rickettsialpox (r. akari), and oriental spotted fever (r. japonica). ticks or mites serve as the vector and reservoir hosts of the rickettsiae. these obligate intracellular bacteria invade vascular endothelial cells, which are damaged directly, causing increased vascular permeability. the ras ... | 1989 | 2677080 |
| acute febrile cerebrovasculitis. a non-spotted fever group rickettsial disease. | in december 1985, a patient was seen with an illness that was clinically compatible with the recently described clinical syndrome of acute febrile cerebrovasculitis, including fever, headache, altered mentation, multifocal neurologic signs, and cerebrospinal fluid pleocytosis. an extensive medical evaluation failed to reveal a cause, until, retrospectively, she was shown to have antibodies to rickettsia typhi. detailed serologic analysis with enzyme immunoassays and protein immunoblots indicated ... | 1989 | 2742443 |
| imported rickettsial african spotted fever in japan. | a 45-year-old japanese man developed a black eschar skin lesion and on the body, a number of erythematous seropapules 2 weeks after his return from south africa. within 24 h of treatment with minocycline he was afebrile and symptomatically much improved. serological tests showed increased antibody titres to spotted fever group rickettsiae (sfgr). from the clinical and serological findings we consider this patient to be the first in japan to have been infected with sfgr in africa. | 1989 | 2757933 |
| epidemiology of boutonneuse fever in western sicily: demonstration of multiple spotted fever group-rickettsiae subtypes. | electrophoretic analysis of the proteins and genomic dna of spotted fever-group rickettsiae isolated from ticks and a human in western sicily show that at least two distinct subtypes other than r. conorii are present in this region. all of the spotted fever-group isolates share common features with other, well-defined spotted fever-group rickettsial species, e.g. r. sibirica, thai tick typhus, and r. rickettsii. based on these data, caution is recommended when identifying species by the more tra ... | 1989 | 2779456 |
| causative agent of spotted fever group rickettsiosis in japan. | since 1984, it has been known that spotted fever group rickettsiosis exists in japan. we isolated three strains of the causative rickettsiae, designated katayama, misaka, and abe, from patients with the disease and studied the characteristics of the isolates. nude mice and cyclophosphamide-treated mice died after infection with the isolates. however, infected normal mice recovered and acquired immunity. infected adult male guinea pigs had fever, a scrotal reaction, and seroconversion. the isolat ... | 1990 | 2108090 |
| detection of murine typhus infection in fleas by using the polymerase chain reaction. | polymerase chain reaction (pcr) amplification of dna was used to detect the etiologic agent of murine typhus, rickettsia typhi, in experimentally infected adult fleas. a primer pair derived from the 17-kilodalton antigen sequence of typhus and spotted fever group rickettsiae was used to amplify a 434-base-pair (bp) fragment of the genome of the murine typhus rickettsiae. the amplified 17-kilodalton protein antigen-specific sequence was detected in ethidium bromide-stained agarose gels in individ ... | 1990 | 2108995 |
| [spotted fever group rickettsiosis on awaji island, japan]. | three cases of spotted fever group rickettsiosis occurring on awaji island, hyogo prefecture, the first reported in the kinki district, are described. the illness appeared from august to september in 1988. high-grade fever and papular erythema were observed in all cases. eschar, lymphadenopathy and hepatomegaly were observed in two-thirds of the cases, respectively. the antibody titers for proteus ox-2 by the weil-felix reaction were elevated, and immunofluorescence test with r. rickettsii of th ... | 1990 | 2119406 |
| [the causative agent from a patient with spotted fever group rickettsiosis in japan on awaji island, hyogo]. | misaka strain was isolated as the causative agent from a patient with spotted fever group rickettsiosis in japan by using nude mice on awaji island, hyogo in september 1988. the nude mice infected with the isolate showed weakness and splenomegaly and died in two or three weeks after the infection. the cyclophosphamide-treated mice infected with the isolate died between four and seven days after the infection. the infected normal mice recovered and acquired immunity. the infected adult male guine ... | 1990 | 2205668 |
| [isolation and identification of the w-88 strain of spotted fever group rickettsiae from a human case in tongliao city, inner mongolia]. | one strain of spotted fever group (sfg) rickettsiae was isolated from a patient with febrile and headache who was missdiagnosed as common cold. the rickettsia was isolated by inoculation of yolk sacs of embryonated hen eggs with the patient's blood. the isolate was named as w-88 following the initial letter of the patient's name. it is the first time to report the isolation of sfg rickettsiae from human being who lived in city in china. in this study we compared the antigens of w-88 strain with ... | 1990 | 2225005 |
| serological typing of spotted fever group rickettsia isolates from zimbabwe. | eight rickettsialike organisms were isolated in tissue culture from ticks of dogs and cattle from various areas of zimbabwe. these isolates and a reference strain, rickettsia conorii simko, were tested by microimmunofluorescence against homologous and heterologous antisera raised in mice. from the titers obtained by this method, specificity differences (spds) were calculated between each of the rickettsiae. only small serological differences were detected among the isolates from ticks obtained f ... | 1990 | 2229356 |
| epidemiology of boutonneuse fever in western sicily: accidental laboratory infection with a rickettsial agent isolated from a tick. | a case is reported of an accidental laboratory infection with a strain of spotted fever-group rickettsiae freshly isolated from a tick collected in western sicily. inoculation into the left thumb of cell-cultured organisms (10(5)/ml) gave rise to clinical signs and symptoms of boutonneuse fever after six days, i.e., a lesion at the point of inoculation, fever, headache, conjunctivitis and myalgias. rickettsiae were isolated from acute-phase blood samples collected from the infected individual an ... | 1990 | 2273984 |
| the prevalence of igg antibodies to spotted-fever group rickettsiae among urban and rural dwelling children in southern israel. | the prevalence of igg antibodies to spotted-fever group rickettsiae was studied in a sample of 1,055 healthy children aged 2-17 years, residents of the desert negev region of southern israel. groups of children from 5 different places of residency were tested: (1) urban children from the city of beer-sheva; (2) children from omer, a suburb of the city; (3) children from rural communes ("kibbutz"); (4) children from small agricultural settlements ("moshav"); and (5) seminomadic bedouin children. ... | 1990 | 2320961 |
| [a case report of spotted fever group rickettsiosis first encountered in shimane prefecture, japan]. | rickettsial infections of a spotted fever group have recently been experience in japan. although there have been 50 cases reported by this time, they were exclusively distributed in the areas along the pacific coast. we report in this paper the first case of spotted fever group rickettsiosis in shimane prefecture, an area faced to the japan sea. a 57 year-old man with high fever, general fatigue and rash was admitted to the hospital of shimane medical university at the end of september 1987, who ... | 1990 | 2335750 |
| tumor necrosis factor alpha and prostaglandin e2 production by human monocyte-derived macrophages infected with spotted fever group rickettsiae. | infection of macrophages by intracellular parasites might modulate production of tumor necrosis factor (tnf) and prostaglandin e2 (pge2), which, in turn, might have a profound effect on the outcome of the infection in vivo. in this study we examined in an in vitro system, the rickettsial yield in human monocyte-derived macrophages (mdm) and the pge2 and tnf production by mdm infected with rickettsia conorii rc, casablanca strain) or israeli spotted fever (isf, g-212 strain). tnf and pge2 were de ... | 1990 | 2378446 |
| rickettsia in texas. | since the first reported case in 1941, rocky mountain spotted fever in humans has been reported from many areas of texas, with two major foci, one located in the north-central region and the other in the eastern region of the state. during the period 1979-1988, 421 cases of rmsf were reported, reaching 108 cases in 1983 and declining in subsequent years. statewide surveillance programs to detect spotted fever group rickettsiae in tick populations were initiated in 1976. in recent years, the sfg ... | 1990 | 2378448 |
| the distribution and dynamics of rickettsia in the tick population of ohio. | a five-year survey of ticks and associated rickettsia in ohio shows a partitioning of spotted fever group rickettsia (namely, rickettsia montana and r. rickettsii) into three areas of the state where the majority of human spotted fever cases occur. the percentage of ticks infected, even in areas with a high incidence of disease, is remarkably low, less than 1%. the statewide infection rate for r. bellii approaches 3%, and this organism appears to be more evenly distributed throughout the state. ... | 1990 | 2378449 |
| prospective study on symptomatic versus asymptomatic infections and serological response to spotted fever group rickettsiae in two rural sites in the negev (southern israel). | 1990 | 2378451 | |
| antigenic polypeptides of israeli spotted fever isolates compared with other spotted fever group rickettsiae. | 1990 | 2378464 | |
| biological characterization of major polypeptides on the surface of spotted fever group rickettsiae. | there are two major polypeptides on the surface of spotted fever group rickettsiae that play important roles as immunogens and possibly relate to the pathogenicity of rickettsial diseases. digestion with trypsin and staphylococcal v-8 protease shows that the 115-kda protein of rickettsia conorii is a trypsin-sensitive, surface-exposed protein. the 135-kda protein is relatively trypsin resistant. both proteins resist heat treatment up to 52 degrees c and maintain their antigenic reactivity with m ... | 1990 | 2378465 |
| prevalence of spotted fever group rickettsia antibody in apodemus speciosus captured in an endemic focus in miyazaki prefecture, japan. | fourteen of apodemus speciosus (large japanese field mouse) were captured near the place where one of the patients with spotted fever group rickettsiosis had been infected, in takaoka town, miyazaki prefecture. in the town, four human cases were reported. all of the mice had antibodies against rickettsia japonica and r. montana. the incidence of the antibody was significantly higher in apodemus mice in the area than in those from nonendemic area. | 1990 | 2395224 |
| use of dna probes for differentiation of spotted fever group and other rickettsiae. | 1990 | 1974125 | |
| molecular genetics of populations of intracellular bacteria: the spotted fever group rickettsiae. | the population structure of tick-borne rickettsiae show the following characteristics: (1) the amount of genetic differentiation between strains within subpopulations is very small. (2) the evolution of the subpopulations does not fit into models based on either host or geographic similarities, suggesting the need for more information on the frequency of vertical versus horizontal transmission of strains between hosts. (3) the species are highly clonal, with little evidence of genetic exchange b ... | 1990 | 1974126 |
| species-specific monoclonal antibodies to rickettsia japonica, a newly identified spotted fever group rickettsia. | a total of 192 hybridomas were developed from mice immunized with rickettsia japonica, a newly identified spotted fever group rickettsia pathogenic for humans. of these hybridomas, 101 were species specific, 37 were spotted fever group reactive, and the other 54 were also reactive with one or more of the other pathogenic species of spotted fever group rickettsiae, rickettsia akari, rickettsia australis, rickettsia conorii, rickettsia rickettsii, and rickettsia sibrica. seven of the species-speci ... | 1990 | 1696280 |
| isolation by a sensitive centrifugation cell culture system of 52 strains of spotted fever group rickettsiae from ticks collected in france. | boutonneuse fever caused by rickettsia conorii is transmitted mainly by the brown dog tick, rhipicephalus sanguineus. we collected 540 ticks in marseille, france, and tried to isolate as many strains of rickettsia as possible. ticks were evaluated for the presence of rickettsia by the hemolymph test and by a new culture system, the centrifugation-shell vial technique. we avoided contamination in the culture system. prior to ticks being submitted to the hemolymph test, they were disinfected. only ... | 1990 | 1696286 |
| polypeptides constituting the antigenic basis for identification of rickettsia sibirica species by the standard serotyping method for spotted fever group rickettsiae. | the antigens of rickettsia sibirica, rickettsia rickettsii, and rickettsia conorii were examined by western immunoblots and the standard immunofluorescent serotyping assay with mouse anti-rickettsia sibirica serum that is used for determining the species identification of spotted fever group rickettsiae. serum was employed prior to absorption and after absorption with purified native or heated rickettsia sibirica. the unabsorbed antiserum, the antiserum absorbed with heated rickettsia sibirica a ... | 1990 | 1697727 |
| [an immunoenzyme test system for detecting rickettsiae of the tick-borne spotted fever group]. | an enzyme immunoassay (eia) test system has been developed for the detection of tick spotty fever (tsf) group rickettsia. a long scheme of immunization in an isogenic system on rabbits has been used with an adjuvant without bacterial components, and based on aluminum hydroxide. this eia test system detects whole soluble r. akari, r. sibirica, and r. conorii antigens and is at least 10-20 times more sensitive than the indirect hemagglutination test. treatment in a temperature gradient permits the ... | 1991 | 1722858 |
| genotypic identification of rickettsiae and estimation of intraspecies sequence divergence for portions of two rickettsial genes. | dna sequences from specific genes, amplified by the polymerase chain reaction technique, were used as substrata for nonisotopic restriction endonuclease fragment length polymorphism differentiation of rickettsial species and genotypes. the products amplified using a single pair of oligonucleotide primers (derived from a rickettsial citrate synthase gene sequence) and cleaved with restriction endonucleases were used to differentiate almost all recognized species of rickettsiae. a second set of pr ... | 1991 | 1671856 |
| dna polymorphism in the conserved 190 kda antigen gene repeat region among spotted fever group rickettsiae. | the 190 kda protein gene of r. rickettsii (r strain) contains a large region of tandemly arranged repeats. homologous sequences were discovered within the genomes of all but one species of spotted fever group rickettsiae. southern blots showed restriction fragment length polymorphisms between species of rickettsiae indicating structural differences among repeat regions. further analysis using polymerase chain reaction techniques indicated the repeat regions vary in size among rickettsiae. in add ... | 1991 | 1677592 |
| a ten years experience on diagnosis of rickettsial diseases using the indirect immunoperoxidase methods. | an accurate diagnosis of tsutsugamushi disease (td) can be made within a few hours after receiving serum specimens by detecting the specific igg and igm antibodies in the patient's serum. using the indirect immunoperoxidase test we found a total of 730 cases of td in 32 out of 47 prefectures when serum samples from 2,224 cases of suspected disease or fever of unknown origin or from patients with febrile exanthema of unknown cause were examined during a 10 years period (from may 1980 till decembe ... | 1991 | 1687642 |
| electron microscopic studies on the in vitro proliferation of spotted fever group rickettsia isolated in japan. | rickettsia was isolated from a patient with japanese spotted fever, and its proliferation in cultured green monkey kidney cells was observed by electron microscopy. in the course of this study, we observed fusion of infected cells to uninfected cells which may be a way of spreading the rickettsiae from a cell to another. on the other hand, whirlpool-like, multilayer membranous structures, similar to the mesosomes of gram-negative bacteria, were sometimes seen in the rickettsial cells. the other ... | 1991 | 1753883 |
| cutaneous eruptions in indian tick typhus. | although frequently unrecognized, rickettsial infections may be an important cause for fever and exanthem in persons presenting to physicians in south india. most often these patients are referred to dermatology departments with a diagnosis of "drug eruption." in the current study the authors analyzed 12 cases of rickettsial fever that were seen in the dermatology department of st. john's medical college hospital, bangalore, between 1985 and 1989. the distinctive cutaneous eruption was found to ... | 1991 | 1757181 |
| transient infections of goats with a novel spotted fever group rickettsia from zimbabwe. | a novel spotted fever group rickettsia has recently been isolated from amblyomma hebraeum ticks in zimbabwe. in a survey of 172 goat sera collected throughout zimbabwe the highest prevalence of antibodies reactive with this rickettsia was in the south of the country, the area where a hebraeum is most commonly found. nine goats were infected using male and female a hebraeum taken from a tick line shown to be infected with the novel rickettsia. by week 3 after infection, seroconversion occurred in ... | 1991 | 1780580 |
| serologic survey of spotted fever group rickettsiosis on hainan island of china. | a serosurvey for antibodies to rickettsia japonica was conducted on hainan island of china. serum specimens were collected from 1,030 outpatients at hospitals in different parts of the island regardless of their diagnosis. only two among 538 serum specimens collected in baoting and tongshi counties, located in the southern part of the island, were demonstrated to contain antibodies reactive with r. japonica at a high dilution. the specimens also reacted with r. rickettsii at the same titer as wi ... | 1991 | 1808466 |
| prevalence of antibodies to spotted fever group rickettsiae in dogs from southeastern australia. | recent epidemiologic data suggests that rickettsia australis, the cause of queensland tick typhus, is present in southeastern australia. in order to further confirm this observation, a canine serosurvey was undertaken to determine if naturally occurring antibodies were present in pet and farm dogs from this newly-recognized endemic area. thirty-five of 312 surveyed dogs (11.2%) had indirect immunofluorescent antibody titers of 1:64 or greater against r. australis antigen. positive control sera w ... | 1991 | 1877719 |
| ecological questions concerning rickettsiae. | the past ten years were characterized by the appearance of several "new" transmissible spotted fever group (sfg) rickettsioses, e.g. israeli, japanese and astrakhan fevers. the factors responsible for their establishment probably include the introduction of chemicals from industry, agriculture and the timber industry into natural habitats. such factors may influence the pathogenicity of these rickettsiae. in this case, in addition to the human influence, the mechanism of the circulation of the a ... | 1991 | 1884774 |
| epidemiology of rickettsial diseases. | rickettsial diseases have a diversity of epidemiologic characteristics reflective of the variety of ecologic situations in which the obligate intracellular bacteria are transmitted to humans. for the spotted fever group (sfg) rickettsiae, rickettsia typhi, r. tsutsugamushi, coxiella burnetii, and the human ehrlichial agent, humans are a dead-end host who plays no role in the maintenance of the organism in nature. all rickettsioses exist as zoonoses. moreover, all rickettsiae are found in infecte ... | 1991 | 1884775 |
| control of rickettsial diseases. | prevention of rickettsial infections is aimed at individual control and epidemic measures (especially in epidemic typhus), vector and rodent control, milk pasteurization (in q fever), chemoprophylaxis and immunoprophylaxis. in vector and rodent control, the main obstacle is the rise in resistance to insecticides and rodenticides. for this reason in vector control, apart from insecticides, enhancement of the natural immunity acquired by animals in response to tick infestation and vaccination with ... | 1991 | 1884780 |
| studies of a "new" rickettsiosis "astrakhan" spotted fever. | the acute febrile disease with characteristic rash seen in astrakhan region and named as "viral exanthema of unknown etiology" was proved to be a spotted fever group rickettsiosis. serological examination of humans from endemic areas by complement fixation test revealed antibodies to r. conorii, r. akari and strains netsvetaev and ar-74 of r. sibirica in titres from 20 to 640 in sera from ill persons. of 429 sera from healthy persons, 5.1% were serologically positive in a titre of 20-40. the pre ... | 1991 | 1884783 |
| spotted fever group rickettsiae or borrelia burgdorferi in ixodes cookei (ixodidae) in connecticut. | immatures and females of ixodes cookei, a hard-bodied tick, were collected from woodchucks and other mammals in the northeastern united states and examined for spotted fever group rickettsiae and borrelia burgdorferi. of the 93 nymphs analyzed by a hemolymph test, 4 (4.3%) harbored rickettsiae. six (15%) of 40 females were also infected. all infected ticks were collected from woodchucks in connecticut. indirect fluorescent antibody staining of midgut tissues from 128 nymphs revealed b. burgdorfe ... | 1991 | 1885748 |
| tick-bite fever in zimbabwe. survey of antibodies to rickettsia conorii in man and dogs, and of rickettsia-like organisms in dog ticks. | as part of a study of tick-bite fever in zimbabwe, the prevalence of antibodies to rickettsia conorii in dogs and humans was examined. blood samples were obtained from 184 dogs in different parts of the country and tested by indirect immunofluorescence. in all, 150 (82%) were positive at a titre of 1/40 or higher. dogs from the south and east of the country showed very high seroprevalence compared with dogs from the main urban centre, harare. human serum was obtained from blood donors, from peop ... | 1991 | 1887350 |
| flinders island spotted fever: a newly recognised endemic focus of tick typhus in bass strait. part 2. serological investigations. | twenty-six cases of a spotted-fever-like illness have been identified on flinders island, tasmania, over a 17 year period. these patients and 335 healthy persons from the island were investigated serologically using the weil-felix agglutination test (proteus sp. antigens ox2, ox19, oxk) and rickettsia-specific microimmunofluorescence. the antigens used in these latter tests comprised one member of the typhus group (rickettsia typhi) and three members of the spotted fever group (rickettsia ricket ... | 1991 | 1898756 |
| the role of rodents as reservoirs for some diseases in new reclaimed areas in north sinai. | in a trial to determine the role of sinai rodents as reservoirs to rickettsial diseases, the ifa technique was used to detect the presence of r. typhi and spotted fever group in blood of some commensal and wild rodent species collected in sinai during the last five years (1985-1989). out of 277 rattus spp. collected in el arish (47.3%) were positive to r. typhi and only (5.9%) of 35 mus musculus were positive to r. typhi. as for gerbillus spp. only (1.5%) of 206 animals were positive for r. typh ... | 1991 | 1908502 |
| transmission of a spotted fever group rickettsia by amblyomma hebraeum (acari: ixodidae). | amblyomma hebraeum, a cattle tick common in southern africa, was demonstrated to be capable of maintaining an infection with an unclassified spotted fever group rickettsia both transtadially and transovarially. all feeding stages of the tick transmitted the infection to rabbits. the rickettsia was isolated and found to be serotypically distinct from three strains of rickettsia conorii by microimmunofluorescence. rabbit serum titers were found to be higher with indirect fluorescent antibody (ifa) ... | 1991 | 1941925 |
| seroepidemiology of spotted fever group rickettsial infections in humans in zimbabwe. | in sera collected throughout zimbabwe the prevalence of antibodies reactive with rickettsia conorii (kenya) and a zimbabwean spotted fever group rickettsia (zsfr) was investigated using an indirect immunofluorescence assay (ifa). a random sample of these sera was also tested using a commercial ifa test. there was close agreement between ifa titres using the african rickettsial antigens and the commercial antigen slides. when differences in titre were detected, these were rarely greater than a tw ... | 1991 | 1942207 |
| isolation of spotted fever group rickettsias from triturated ticks using a modification of the centrifugation-shell vial technique. | a modification of the centrifugation-shell vial technique was used to isolate spotted fever group (sfg) rickettsias from triturated ticks which had previously been stored at -80 degrees c for up to 7 months. sfg rickettsias were successfully isolated in vero cells from all 7 haemolymph positive ticks (amblyomma hebraeum) used in the experiment. attempts were also made to use these tick triturates to establish sfg rickettsial infections in tissue culture. vero cells were used for 5 of the tick tr ... | 1991 | 1949146 |
| spotted fever group rickettsial infections in australia. | more than four decades ago, rickettsia australis was discovered to be the etiologic agent of queensland tick typhus (qtt), yet many unanswered questions persist about the ecology, epidemiology, and clinical features of this disease. we review 46 previously published cases of qtt along with 16 cases discovered by active surveillance. qtt is usually a mild disease. patients often have regional lymphadenopathy and eschars. some have vesicular rashes. because clinical features overlap, serologic tes ... | 1991 | 1962102 |
| spotted fever in east gippsland, victoria: a previously unrecognised focus of rickettsial infection. | a new focus of spotted fever group rickettsial infection has been recognised in east gippsland, victoria. seven cases have been identified among melbourne residents after they holidayed in the area. the infections were confirmed serologically. the precise identity of the rickettsia has not been determined. | 1991 | 1986189 |
| genetic characterization and transovarial transmission of a typhus-like rickettsia found in cat fleas. | the identification of apparently fastidious microorganisms is often problematic. dna from a rickettsia-like agent (called the elb agent) present in cat fleas could be amplified by pcr with conserved primers derived from rickettsial 17-kda common protein antigen and citrate synthase genes but not spotted fever group 190-kda antigen gene. alu i sites in both the 17-kda and citrate synthase pcr products obtained with the rickettsia-like agent and rickettsia typhi were different even though both age ... | 1992 | 1729713 |
| intrafamilial outbreak of mediterranean spotted fever. | the existence of intrafamilial outbreaks of spotted-fever group rickettsioses has seldom been reported, and their true incidence is not known. we here report the occurrence of mediterranean spotted fever (msf) in three members of a family: a boy, his grandmother and his grandfather. the infection resolved uneventfully in the boy, and followed a more protracted course in the two older patients, who suffered complications including drowsiness, clotting defects and acute renal failure. this finding ... | 1992 | 1732403 |
| spotted fever in hong kong. | a previously healthy 7-year-old hong kong-born caucasian child developed sudden onset fever, followed by a generalized rash and systemic symptoms of rigor and prostration, mucous membrane involvement (conjunctivitis) and arthralgia. he lives in a rural area of hong kong and has been in contact with various domestic animals--rodents, dogs and cows. chloramphenicol 50 mg/kg/day was given on day 4 with rapid response. subsequent weil-felix test and specific serology suggested the diagnosis of ricke ... | 1992 | 1280039 |
| [current status of knowledge on the epidemiology of rickettsiosis in africa]. | rickettsioses have been reported all over africa. serologic investigations have been driven using non specific methods as giroud microagglutination and weil-felix test which led to numerous false positive. this explains the difficulties encountered in the evaluation of the prevalence of such diseases in africa. however, three recent studies made in tunisia, central africa and zimbabwe show that seroprevalence of spotted fever group rickettsiae infections is close to 45% using mif as reference me ... | 1992 | 1292794 |
| determination of genome sizes of rickettsia spp. within the spotted fever group, using pulsed-field gel electrophoresis. | the chromosome lengths of six spotted fever group rickettsia species (rickettsia rickettsii, r. conorii, r. rhipicephali, r. sibirica, r. australis, and r. akari) were estimated by pulsed-field gel electrophoresis. the genome size of r. rickettsii was about 2,100 kb, but the chromosome lengths of the five other species were, surprisingly, much lower and ranged between 1,200 and 1,300 kb. | 1992 | 1331027 |
| identification of spotted fever group rickettsiae using polymerase chain reaction and restriction-endonuclease length polymorphism analysis. | in order to facilitate the isolation and identification of spotted fever group (sfg) rickettsiae from their tick vectors, we used the centrifugation shell vial technique or traditional isolation procedures and genotypic identification using the restriction fragment length polymorphism analysis of polymerase chain amplified fragments. the presence of rickettsia conorii both in rhipicephalus sanguineus ticks collected in southern france, and in rhipicephalus simus and haemaphysalis leachi from zim ... | 1992 | 1350164 |
| serum antibodies in rickettsia patients as determined by immunoblotting technique. | the western-blot technique (wb) was used to determine which polypeptides of israeli spotted fever (isf) isolates and other spotted fever group rickettssia (sfgr) reference isolates (g212, s484, a828) and two reference strains. r. rickettsii (sheila smith strain) and r. conorii (boutonneuse fever), were used as antigen sources for the wb. immunoperoxidase assay (ipa) seropositive (titer greater than 80) and seronegative (titer less than) sera were examined with the separated polypeptides of the a ... | 1992 | 1350167 |
| comparison of structural polypeptides, detected by immunoblotting technique, in the sera of spotted fever group rickettsia positive cases--symptomatic versus asymptomatic. | in an attempt to characterize the nature of symptomatic versus asymptomatic spotted fever group rickettsia (sfgr) infection, the immune response to r. conorii (boutonneuse fever) structural polypeptides was studied by western-blot immunoassay. sera from immunoperoxidase assay (ipa), sfgr seropositive (titre greater than or equal to 80) individuals, symptomatic and asymptomatic and from sfgr seronegative (ipa titre less than 80) individuals living in a kibbutz community in the desert region of so ... | 1992 | 1350173 |
| the reactivity between rickettsiae and weil-felix test antigens against sera of rickettsial disease patients. | of the sera which were positive to rickettsia tsutsugamushi by indirect immunoperoxidase test, approximately 80% sera were positive to a proteus oxk antigen by weil-felix test at 10 or more days after the onset of fever, while only 10% sera were positive within 9 days from the onset of fever. in elisa using the oxk antigen, almost all of the paired sera of tsutsugamushi disease (td) patients increased on the igm antibody titres with the rise of their titres by weil-felix test, whereas the igg an ... | 1992 | 1350175 |
| comparison of serologic typing, sodium dodecyl sulfate-polyacrylamide gel electrophoresis protein analysis, and genetic restriction fragment length polymorphism analysis for identification of rickettsiae: characterization of two new rickettsial strains. | in 1990, 17 adult rhipicephalus turanicus ticks were collected in the south of france. two spotted fever group rickettsiae, mtu1 and mtu5, were isolated from the hemolymphs of two of these ticks by the centrifugation shell-vial technique by using hel cells. these isolates were compared with reference spotted fever group rickettsial serotypes by using three identification methods: microimmunofluorescence serologic typing, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page), and p ... | 1992 | 1354221 |
| human and tick spotted fever group rickettsia isolates from israel: a genotypic analysis. | the genomes of spotted fever group rickettsiae isolated in different geographical areas of israel (two from ticks and four from humans, obtained over a span of 20 years) were studied by polymerase chain reaction (pcr) and restriction endonuclease fragment length polymorphism (rflp) analysis. the human isolates were obtained from patients suffering from rickettsial disease of different degrees of severity. the pcr products obtained with five pairs of oligonucleotide primers (two primer sets deriv ... | 1992 | 1356998 |
| african tick-bite fever: a new spotted fever group rickettsiosis under an old name. | 1992 | 1357393 | |
| antigenic diversity of rickettsia conorii. | analysis of seven strains designated as rickettsia conorii for reactivity with a panel of 12 monoclonal antibodies to surface-protein epitopes of spotted fever group rickettsiae and by western immunoblotting with standard serotyping sera revealed remarkable antigenic diversity. rickettsial strains from france, morocco, ethiopia, kenya, south africa, india, and the ussr differed from one another in reactivity with at least one and as many as five monoclonal antibodies. simko and indian strains we ... | 1992 | 1379008 |
| serological studies of antigenic similarity between japanese spotted fever rickettsiae and weil-felix test antigens. | acute and convalescent-phase sera obtained from 10 patients infected with a japanese strain of spotted fever group (sfg) rickettsia were tested by the indirect immunoperoxidase test, the weil-felix test, an enzyme-linked immunosorbent assay (elisa), and immunoblotting. by the weil-felix test, the reactivity of these sera to the ox2 antigen was higher than those to the ox19 antigen, as is the case with sera from persons infected with other sfg rickettsiae. by elisa, the titers of immunoglobulin m ... | 1992 | 1383270 |
| evidence of the presence of spotted fever group rickettsiae in dogs and dog ticks of the central provinces in spain. | to assess canine exposure to spotted fever group rickettsiae in the central provinces of spain, ticks removed from dogs were studied by immunofluorescence (if) staining. twenty-eight out of 65 (43.0%) samples from ticks were positive. sera from 58 dogs were also collected and the presence of antibodies to rickettsia conorii studied. thirty-four (58.6%) dogs presented significant titers by if. surveillance data from these provinces show the presence of boutonneuse fever cases during recent years, ... | 1992 | 1397228 |