exudates and Typhus--Epidemic-Louse-Borne

Rickettsioses of the typhus group (TG) and spotted fever group (SFG) are emerging bacterial infections worldwide, especially in the tropics. Only a few studies on these pathogens and their respective clinical diseases have been conducted in Malaysia. Here, we performed a seroprevalence study among 544 healthy, afebrile indigenous people (Orang Asli) from peninsular Malaysia for TG and SFG rickettsioses in nine rural and peri-urban settlements. The study population encompassed children, adolescents, and adults. The overall seroprevalence of rickettsiosis in the Orang Asli was 48.5%, with 27.9% seroprevalence against TG rickettsiae and 20.6% seroprevalence against SFG rickettsiae. In 7.9% of the study participants, antibodies against both rickettsial groups were found. The highest seropositivity rates against TG and SRG rickettsiae were detected in young children and adults. Overall, there were no gender differences. Seroprevalences were similar among inhabitants of different settlements, except for two localities. More studies are needed to shed more light on the ecology and risk factors for TG and SFG rickettsioses in Malaysia.

Topics: Adolescent; Child; Child, Preschool; Female; Humans; Infant; Malaysia; Male; Population Groups; Rickettsia; Seroepidemiologic Studies; Spotted Fever Group Rickettsiosis; Typhus, Epidemic Louse-Borne

A seroepidemiology study was done in response to the recent increase of Endemic Typhus cases diagnosed at University Hospital. The serosurvey was based on doctors' request for the Weil Felix (WF) or the Indirect Immunoperoxidase (IIP) test in Pyrexia of Unknown Origin (PUO) patients for the years 1991 to 1997. Over the 7 years, we found that the incidence of Endemic typhus is increasing with gender (male:female = 2:1), age (20-40 years) and race distribution (Indians > Malay > Chinese) that reflects socioeconomic circumstances. A commercially available ELISA dot assay [INDX (E2R3) Dip-S-Ticks], for the detection of antibodies against R. typhi was compared with the indirect immunoperoxidase test (IIP). The ELISA assay was done against 219 IIP tested sera. The Dip-S-Ticks was found to be comparable to the IIP with a sensitivity of 91.7% and specificity of 92.8% at cut-off titres of > 1:80 IIP.

Topics: Adult; Antibodies, Bacterial; Enzyme-Linked Immunosorbent Assay; Female; Humans; Malaysia; Male; Prevalence; Rickettsia typhi; Serologic Tests; Typhus, Epidemic Louse-Borne

People in 5 Orang Ulu villages in Sarawak, Malaysia were tested for rickettsial infection by Weil-Felix reaction and by indirect immunoperoxidase reaction. Of those surveyed 9.6% were positive for typhus. Of the positives, 3.8% were positive for tick typhus (7/11), scrub typhus (4/11) or endemic typhus (1/11). The incidence of typhus was higher among semi-nomadic Penans compared with the settled Kayans.

Topics: Adolescent; Adult; Aged; Ethnicity; Female; Humans; Immunoenzyme Techniques; Malaysia; Male; Middle Aged; Rural Health; Seroepidemiologic Studies; Typhus, Epidemic Louse-Borne

Forty-four serum samples of various reactivities to rickettsial antigens demonstrated by the indirect immunoperoxidase technique were tested with INDX Dip-S-Ticks (INDX Integrated Diagnostics Inc., USA) Kit for the detection of tick borne diseases. The kit utilised Rickettsia rickettsii the causative agent of Rocky Mountain spotted fever (RMSF) as antigens. The samples positive for endemic typhus were also tested against R. typhi, the agent for endemic typhus by the same method. The aim of this study was to determine the extent of cross-reactivity of R. rickettsii with rickettsial infections in Malaysia. Nine out of 12 tick typhus, 4 out of 10 scrub typhus and 4 out of 12 endemic typhus samples cross reacted with R. rickettsii. Ten out of 12 endemic samples were positive with R. typhi by the same method. From the study, we concluded that the INDX Dip-S-Ticks Kit can be used as a rapid screening test to detect endemic and tick-borne rickettsial infections in Malaysia but a second serological test is strongly recommended on all weakly reactive cases.

Topics: Animals; Antigens, Bacterial; Cross Reactions; Evaluation Studies as Topic; Humans; Malaysia; Reagent Kits, Diagnostic; Rickettsia; Ticks; Typhus, Epidemic Louse-Borne

Topics: Animals; Culicidae; Malaysia; Mites; Myanmar; Typhus, Epidemic Louse-Borne

Topics: Animals; Biometry; Chemoprevention; Chloramphenicol; Culicidae; Malaysia; Scrub Typhus; Typhus, Epidemic Louse-Borne