No abstract available.
Rickettsia typhi* ; Rickettsia*

No abstract available.
Antibodies, Monoclonal* ; Rickettsia typhi* ; Rickettsia*

No abstract available.
Antibodies, Monoclonal* ; Rickettsia typhi* ; Rickettsia*

No abstract available.
Electrophoresis, Polyacrylamide Gel* ; Immunoblotting* ; Korea* ; Rickettsia typhi* ; Rickettsia*

Murine typhus is an acute febrile illness caused by Rickettsia typhi. It is one of the four major acute febrile illnesses in Korea during autumn. To study a species-specific antigen of R. typhi, two clinical isolates (87-91 and 87-100) and two reference strains (VR-144 and VR-738) were analyzed by mouse antisera and monoclonal antibodies (MAbs). On SDS- polyacrylamide gel electrophoresis (PAGE), R. typhi showed major antigen bands of 135, 80, 75, 64, 47, 22, and 19 kDa and these bands differed with those of other species. On Western blot analysis, the MAbs reacting only with R. typhi could only detect 135 kDa protein. The 135 kDa protein appeared to be the species-specific antigen. Other MAbs showing cross-reactivity with R. prowazekii reacted with 135 kDa protein in fresh culture supernatant of R. typhi infected host cell. However, the cross-reacting antibody did also react with smaller protein bands, most of which seem to be degradation products of the 135 kDa protein since they increase in old protein stocks purified from R. typhi harvested from infected host cell. These suggest that 135 kDa protein is unstable and the R. typhi specific epitopes are located at the regions of 135 kDa protein that are removed when the protein is degraded. The 135 kDa protein or its specific and stable recombinant protein would serve an important target for the development of vaccine and specific diagnostic antigen.
Animals ; Antibodies, Monoclonal ; Blotting, Western ; Electrophoresis, Polyacrylamide Gel ; Epitopes ; Immune Sera ; Korea ; Mice ; Rickettsia typhi* ; Rickettsia* ; Typhus, Endemic Flea-Borne

The crystalline surface layer protein (SLP) and a 28-32 kDa antigen of Rickettsia typhi were known as strong immunogens. We previously reported a cloning and sequence analysis of the SLP gene of R. typhi (slpT) and showed that the open reading frame of this gene encodes both the SLP and a 32-kDa protein. Our study also showed that a 48-kDa protein reacted strongly with polyclonal antiserum of a patient with murine typhus. In this study, we produced three recombinant proteins (SLP, 32-kDa, and 48-kDa protein) in E. coli as fusion proteins with maltose binding proteins. The reactivity of these proteins with patients' sera was investigated.
Clone Cells* ; Cloning, Organism* ; Crystallins ; Humans ; Maltose-Binding Proteins ; Open Reading Frames ; Recombinant Proteins ; Rickettsia typhi* ; Rickettsia* ; Sequence Analysis ; Typhus, Endemic Flea-Borne

Coxiella burnetii is the etiological agent of Q fever, that may occur either acutely or the chronically. To understand the seroepidemiological patterns of C. burnetii infection in Korea, we examined a total of 3,178 sera from patients with acute febrile episodes by using indirect immunofluorescence assay (IFA) for detectable antibodies to C. burnetii and other eight rickettsial antigens. The IFA seropositivity>or=1:20 for C. burnetii phase II was 11.5% (368 out of 3,178 sera). The co-existence of antibodies to other rickettsial antigens was found in 216 out of the 368 positive sera. Thirty-seven point five percent (n=138) had antibodies to R. tsutsugamushi (cutoff>or=1:20), 16% (n=59) to Ehrlichia sennetsu, 14.9% (n=55) to Rickettsia typhi, 13.5% (n=50) to R. akari, 11.4% (n=42) to R. japonica, 8.9% (n=33) to R. prowazekii, 7.6% (n=28) to R. sibirica, and 6.7% (n=25) to R. conorii by IFA, respectively. These results are consistent with previous reports documenting diverse serum cross-reactivity in chronic Q fever. Therefore we excluded the samples that reacted to other rickettsial antigens at same or higher titers than to C. burnetii, resulting in the seropositive rate of 4.1%. The serological prevalence was 2% (n=64) when the conventional cut-off titer of 1:80 was used. Our results suggest that infections with C. burnetii are more prevalent than expected previously and should be differentially diagnosised for febrile illness occurring after exposure to ticks or other vectors.
Antibodies ; Coxiella burnetii* ; Coxiella* ; Diagnosis ; Fluorescent Antibody Technique, Indirect ; Humans ; Korea ; Neorickettsia sennetsu ; Prevalence ; Q Fever ; Rickettsia ; Rickettsia typhi ; Seroepidemiologic Studies* ; Ticks

Murine (endemic) typhus is a zoonotic infection caused by Rickettsia typhi (formerly known as Rickettsia mooseri). Rickettsia typhi is an obligate intracellular organism that multiplies within the cytoplasm of mainly endothelial cells. It is transmitted from rats by injection of contaminated flea feces into the skin of the host. The disease manifests itself with the gradual onset of fever, myalgia, and headache appearing 7-14 days after infection. A maculopapular rash is found in some patients (proportions ranging from 20 to 80% in different series). We report a rare case of murine typhus with presentation of hemorrhagic vesicles and dyspnea which was treated at our emergency department, and we give a brief review of the literature.
Animals ; Cytoplasm ; Dyspnea* ; Emergency Service, Hospital ; Endothelial Cells ; Exanthema ; Feces ; Fever ; Headache ; Humans ; Myalgia ; Rats ; Rickettsia ; Rickettsia typhi ; Siphonaptera ; Skin ; Typhus, Endemic Flea-Borne* ; Typhus, Epidemic Louse-Borne ; Zoonoses

Hemorrhagic fever with renal syndrome (HIFRS), scrub typhus, murine typhus and leptospirosis have been the principal acute febrile diseases in Korea. To evaluate the seroepidemiologic patterns of acute febrile illness, sera collected from 2,423 patients in 1996 were examined for antibodies against Hantaan virus, Orientia tsutsugamushi, Rickettsia typhi, and Borrelia burgdorferi by indirect immunofluorescent antibody technique (IFA) and macroscopic agglutination test for Leptospira interogans. Seropositive cases against O. tsutsugamushi, Rickettsia typhi, Leptispira interogans and Hantaan virus were 192 (7.9%), 193 (8.0%), 12 (0.5%) and 324 (13.4%), respectively. Male was more affected in HFRS and murine typhus contrasting to scrub typhus and leptospirosis in female. Most positive cases occurred during October and November for scrub typhus, and during November and December for HFRS. These results showed similar patterns with previous epidemical data for recent couple of years, and possibly implied no significant changes occurred in ecologic situations for acute febrile diseases in Korea.
Agglutination Tests ; Antibodies ; Borrelia burgdorferi ; Female ; Hantaan virus ; Hemorrhagic Fever with Renal Syndrome ; Humans ; Korea* ; Leptospira ; Leptospirosis ; Male ; Orientia tsutsugamushi ; Rickettsia typhi ; Scrub Typhus ; Typhus, Endemic Flea-Borne

Rickettia typhi is an obligate intracellular organism and usually seen microscopically as gram-negative pleomorphic coccobacilli. Murine typhus is an acute febrile illness caused by R. typhi and transmitted to human by fleas. Fever, skin rash, headache, and myalgia characterize the clinical illness. The risk for laboratory personnel is from exposure to infectious aerosols, accidental inoculation, or exposure to bites by infected ectoparasites. A 27-year old man was admitted to the hospital because of fever and myalgia. He had worked with R. typhi in a laboratory and was exposed to R. typhi 10 days ago. The present illness began seven days before admission, when he developed high fever and conjunctival injection. One day before admission, he developed generalized erythematous skin rash and generalized edema. Immunofluorescence test with rickettsial antigen was positive at 1:4,096 on admission. He received 200 mg of doxycycline for 7 days and became afebrile on the third day after treatment.
Adult ; Aerosols ; Doxycycline ; Edema ; Exanthema ; Fever ; Fluorescent Antibody Technique ; Headache ; Humans ; Laboratory Personnel ; Myalgia ; Rickettsia typhi ; Siphonaptera ; Typhus, Endemic Flea-Borne*