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detection of murine typhus infected fleas with an enzyme-linked immunosorbent assay.an enzyme-linked immunosorbent assay (elisa) for the detection of rickettsia typhi antigen in homogenates of pooled or individual laboratory infected fleas is described. the assay uses a double sandwich technique, employing a pool of monoclonal antibodies to capture the antigen and a hyperimmune rabbit serum for antigen detection. using pools of r. typhi infected xenopsylla cheopis, ctenocephalides felis, and leptopsylla segnis, the sensitivity of the elisa was compared with direct fluorescent a ...19892499204
experimental transmission of murine typhus by xenopsylla cheopis flea bites.transmission of rickettsia typhi to rats by the bites of xenopsylla cheopis (rothschild) fleas was investigated. procedures rigorously excluded the possibility of contamination of the host skin by flea faeces. fleas with r. typhi infection (21-25 days post-infection) which fed through bolting cloth (45 min exposure to ten fleas) transmitted rickettsiae with a success rate of 20%. infective fleas allowed free access to their host for 8 h (10-15 fleas/rat) gave transmission rates of 45-68%. they w ...19892519693
suppression of rickettsia typhi transmission in fleas maintained on murine typhus-immune rats.the presence of host antibodies against rickettsia typhi in the hemolymph of xenopsylla cheopis fed on immune rats was studied using an indirect immunofluorescent antibody (ifa) test and enzyme-linked immunosorbent assay (elisa). the time course experiment revealed that antibody to r. typhi appears in the flea hemolymph after 18 hr exposure to host and persists for 24 hr. ifa tests utilizing specific antisera to rat igg (fc) and rat igg (fab) fragments, indicate that some unaltered rat igg to r. ...19873120611
murine typhus among khmers living at an evacuation site on the thai-kampuchean border.an outbreak of febrile disease involving 170 khmer adults at an evacuation site in thailand occurred during the dry season of 1986, only 8 months after the camp was constructed. the illnesses were characterized by persistent fever, retro-orbital headache, myalgias, and clinical response to tetracycline within 2-3 days. the symptoms, effectiveness of tetracycline, and presence of a large rat population raised the suspicion of murine typhus. fourteen (74%) of 19 patients had elevated or rising ant ...19883124646
transmission cycle of murine typhus in greece.a field study, based on a follow up of the 49 human cases of the disease that occurred on the island of evia in 1985, has established the transmission cycle of murine typhus in greece for the first time. in 1993, two types of traps were used to catch 53 rats, all of them rattus norvegicus, in the localities where the cases had occurred. some 300 fleas, all of them probably xenopsylla cheopis, and a few ticks and mites were collected from the rats. eight of the fleas were found positive for ricke ...19947893179
murine typhus: updated roles of multiple urban components and a second typhuslike rickettsia.studies using serologic and polymerase chain reaction-(pcr) facilitated analysis of field samples from southern texas indicate the presence of rickettsia typhi and elb agent infected cat fleas, ctenocephalides felis (bouché), and the first observation of elb infected vertebrates (opossums). the elb agent is a recently described typhus-like rickettsia that is not distinguished from r. typhi or r. prowazekii by currently available serologic reagents. restriction digests of pcr products from 399 fl ...19947966170
genotypic identification of murine typhus rickettsia in rats and their fleas in an endemic area of greece by the polymerase chain reaction and restriction fragment length polymorphism.forty-nine cases of murine typhus were diagnosed in recent years in residents of several communities around the city of chalkis, the capital of the prefecture of evia. (euboea) evia is an island connected to central mainland greece by a bridge. to investigate the endemicity of murine typhus in this area, 226 fleas (xenopsylla cheopis) and blood samples were collected from 53 rats (rattus norvegicus) trapped in this area. the polymerase chain reaction followed by restriction fragment length polym ...19968615457
prevalence of vectors of the spotted fever group rickettsiae and murine typhus in a bedouin town in israel.a survey of the vectors of spotted fever group rickettsiae and of murine typhus was carried out in rahat, a bedouin town in the negev desert, where the diseases are endemic. houses with known cases of spotted fever group rickettsiae or murine typhus were compared with those without reported clinical cases. a neighboring jewish community, lehavim, where no cases of spotted fever group rickettsiae and murine typhus were reported in recent years, was used as a control. in the houses of patients wit ...200111372975
evidence of rickettsia typhi and the potential for murine typhus in jayapura, irian jaya, indonesia.murine typhus (etiologic agent: rickettsia typhi) is endemic to indonesia, especially on the highly populated island of java. a survey of rodents from irian jaya, the eastern-most province of indonesia, indicated striking geographic variation in risk factors associated with murine typhus. murid rodents (n = 112) collected from two villages in the arso district of northeastern irian jaya, were found to be free of ectoparasites normally associated with transmission of r. typhi (i.e., xenopsylla ch ...200212164301
an experimental model of human body louse infection with rickettsia typhi.murine (endemic) typhus caused by rickettsia typhi, one of the most widely distributed arthropod-borne diseases, is transmitted to humans mainly by the oriental rat flea. the human body louse, pediculus humanus corporis, has been suspected to have a role in the transmission of r. typhi to humans. to evaluate the potential role of pediculus humanus corporis as a vector of murine typhus, we used r. typhi in an experimental model of human body louse infection previously used with r. prowazekii. a r ...200312860699
structural features of lipopolysaccharide from rickettsia typhi: the causative agent of endemic typhus.rickettsia typhi causes endemic typhus, a relatively mild, acute febrile illness characterized by headache and macular rash. it is maintained in rodents and transmitted to humans by flea xenopsylla cheopis. r. typhi contains a lipopolysaccharide thought to display a noticeable antigenic activity. we examined its structural features and it appears that the o-specific chain of the r. typhi lps is composed mainly of the alternating glc and quinac residues linked by 1-->4 bonds.200516481524
surveillance of egyptian fleas for agents of public health significance: anaplasma, bartonella, coxiella, ehrlichia, rickettsia, and yersinia pestis.serologic surveys in egypt have documented human and animal exposure to vector-borne bacterial pathogens, but the presence and distribution of these agents in arthropods has not been determined. between july 2002 and july 2003, fleas were collected from 221 mammals trapped in 17 cities throughout egypt. a total of 987 fleas were collected, representing four species (ctenocephalides felis, echidnophaga gallinacea, leptopsylla segnis, and xenopsylla cheopis); 899 of these fleas were x. cheopis fro ...200616837707
rickettsia felis in xenopsylla cheopis, java, indonesia.rickettsia typhi and r. felis, etiologic agents of murine typhus and fleaborne spotted fever, respectively, were detected in oriental rat fleas (xenopsylla cheopis) collected from rodents and shrews in java, indonesia. we describe the first evidence of r. felis in indonesia and naturally occurring r. felis in oriental rat fleas.200616965716
genome-wide screen for temperature-regulated genes of the obligate intracellular bacterium, rickettsia typhi.the ability of rickettsiae to survive in multiple eukaryotic host environments provides a good model for studying pathogen-host molecular interactions. rickettsia typhi, the etiologic agent of murine typhus, is a strictly intracellular gram negative alpha-proteobacterium, which is transmitted to humans by its arthropod vector, the oriental rat flea, xenopsylla cheopis. thus, r. typhi must cycle between mammalian and flea hosts, two drastically different environments. we hypothesize that temperat ...200818412961
rickettsia typhi and r. felis in rat fleas (xenopsylla cheopis), oahu, hawaii.rickettsia typhi (prevalence 1.9%) and r. felis (prevalence 24.8%) dna were detected in rat fleas (xenopsylla cheopis) collected from mice on oahu island, hawaii. the low prevalence of r. typhi on oahu suggests that r. felis may be a more common cause of rickettsiosis than r. typhi in hawaii.200818826827
rickettsia typhi and rickettsia felis in xenopsylla cheopis and leptopsylla segnis parasitizing rats in cyprus.fleas collected from rats during a three-year period (2000-2003) in 51 areas of all provinces of cyprus were tested by molecular analysis to characterize the prevalence and identity of fleaborne rickettsiae. rickettsia typhi, the causative agent of murine typhus, was detected in xenopsylla cheopis (4%) and in leptopsylla segnis (6.6%). rickettsia felis was detected in x. cheopis (1%). this is the first report of r. typhi in x. cheopis and l. segnis from rats, in cyprus, and the first report of r ...201021118938
urban focus of rickettsia typhi and rickettsia felis in los angeles, california.abstract classic murine typhus, caused by rickettsia typhi, is endemic in the continental united states in areas of texas and southern california. we conducted an environmental investigation in an urban area of los angeles identified as the probable exposure site for a case of murine typhus. four rattus norvegicus heavily infested with xenopsylla cheopis (average 32.5 fleas per animal, range 20-42) were trapped, and fleas, blood, and tissues were collected. dnas from all specimens were tested fo ...201021142968
rickettsial infections of fleas collected from small mammals on four islands in indonesia.ectoparasites were sampled from small mammals collected in west java, west sumatra, north sulawesi, and east kalimantan, indonesia, in 2007-2008 and were screened for evidence of infection from bacteria in the rickettsaceae family. during eight trap nights at eight sites, 208 fleas were collected from 96 of 507 small mammals trapped from four orders (379 rodentia; 123 soricomorpha; two carnivora; three scandentia). two species of fleas were collected: xenopsylla cheopis (n = 204) and nosopsyllus ...201021175069
molecular detection of rickettsia felis and candidatus rickettsia asemboensis in fleas from human habitats, asembo, kenya.the flea-borne rickettsioses murine typhus (rickettsia typhi) and flea-borne spotted fever (fbsf) (rickettsia felis) are febrile diseases distributed among humans worldwide. murine typhus has been known to be endemic to kenya since the 1950s, but fbsf was only recently documented in northeastern (2010) and western (2012) kenya. to characterize the potential exposure of humans in kenya to flea-borne rickettsioses, a total of 330 fleas (134 pools) including 5 species (xenopsylla cheopis, ctenoceph ...201323675818
high prevalence of rickettsia typhi and bartonella species in rats and fleas, kisangani, democratic republic of the congo.the prevalence and identity of rickettsia and bartonella in urban rat and flea populations were evaluated in kisangani, democratic republic of the congo (drc) by molecular tools. an overall prevalence of 17% bartonella species and 13% rickettsia typhi, the agent of murine typhus, was found in the cosmopolitan rat species, rattus rattus and rattus norvegicus that were infested by a majority of xenopsylla cheopis fleas. bartonella queenslandensis, bartonella elizabethae, and three bartonella genot ...201424445202
dual exposure of rickettsia typhi and orientia tsutsugamushi in the field-collected rattus rodents from thailand.field-collected rodents and fleas from ten provinces covering four regions of thailand were investigated for possible rickettsial pathogen infections. the 257 trapped-rodents belonged to 12 species. five species of genus rattus accounted for 93% of the total capture, of which rattus exulans and rattus norvegicus were the two major species caught. all flea specimens, removed from trapped rodents, were identified as xenopsylla cheopis. the pcr technique was performed on ectoparasite specimens to d ...201424820571
molecular and serological evidence of flea-associated typhus group and spotted fever group rickettsial infections in madagascar.rickettsiae are obligate intracellular bacteria responsible for many febrile syndromes around the world, including in sub-saharan africa. vectors of these pathogens include ticks, lice, mites and fleas. in order to assess exposure to flea-associated rickettsia species in madagascar, human and small mammal samples from an urban and a rural area, and their associated fleas were tested.201728259176
detection of rickettsia felis, rickettsia typhi, bartonella species and yersinia pestis in fleas (siphonaptera) from africa.little is known about the presence/absence and prevalence of rickettsia spp, bartonella spp. and yersinia pestis in domestic and urban flea populations in tropical and subtropical african countries.201425299702
murine typhus in returned travelers: a report of thirty-two cases.murine typhus, caused by rickettsia typhi and transmitted mainly by the rat fleas, xenopsylla cheopis, has emerged in the field of travel medicine. we analyzed retrospectively the epidemiological, clinical, and biological characteristics of the 32 murine typhus cases that were diagnosed during the past 3 years at the world health organization collaborative center for rickettsial diseases, marseille, france. all of the cases occurred in travelers and most of them had returned from africa (n = 13 ...201222665617
murine typhus: clinical and epidemiological aspects.is an intracellular bacteria who causes murine typhus. his importance is reflected in the high frequency founding specific antibodies against rickettsia typhi in several worldwide seroepidemiological studies, the seroprevalence ranging between 3-36%. natural reservoirs of r. typhi are rats (some species belonging the rattus genus) and fleas (xenopsylla cheopis) are his vector. this infection is associated with overcrowding, pollution and poor hygiene. typically presents fever, headache, rash on ...201224893060
opossums and cat fleas: new insights in the ecology of murine typhus in galveston, texas.murine typhus is an acute undifferentiated febrile illness caused by rickettsia typhi the classic reservoir (rattus spp.) and flea vector (xenopsylla cheopis) were once culprits of murine typhus in the united states. vector and rodent control efforts have drastically decreased the prevalence of disease, except in a few endemic foci where opossums and cat fleas play a role in transmission. since 2012, there has been a reemergence of murine typhus in galveston, tx. we hypothesize that opossums and ...201627273642
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