| some biological properties of an endotoxic lipopolysaccharide from the typhus group rickettsiae. | a lipophilic thermostable lipopolysaccharide (lps) complex was isolated by phenol extraction from purified suspensions of the typhus group rickettsiae. the lps complex is antigenic and possesses some endotoxic properties such as toxicity for actinomycin d-treated mice, pyrogenicity for rabbits and guinea pigs, ability to elicit hypothermia in white rats and local schwartzman reaction and active cutaneous anaphylaxis in rabbits. | 1977 | 22240 |
| seroprevalence of rickettsia typhi and rickettsia conorii infection among rodents and dogs in egypt. | a serological survey of 1813 rodent and 549 dog sera, collected from 1979 to 1986 from animals in 16 egyptian governorates were tested for antibody to rickettsia typhi and rickettsia conorii by the indirect fluorescent antibody test. only three of 82 (4%) sera from rattus rattus collected near aswan had antibody to r. conorii. the prevalence of r. typhi antibody in dog sera was only 0.4% (n = 549) while 25% (n = 547) of rattus norvegicus and 11% (n = 1138) of r. rattus had measurable antibodies. ... | 1989 | 2509729 |
| 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 ... | 1996 | 8615457 |
| 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 ... | 2001 | 11372975 |
| urban zoonoses caused by bartonella, coxiella, ehrlichia, and rickettsia species. | the last half of the 20th century witnessed an increase in the occurrence and recognition of urban zoonoses caused by members of the genera bartonella, coxiella, ehrlichia, and rickettsia, all traditionally considered to be members of the family rickettsiaceae. in recent years, new human pathogens (bartonella elizabethae, bartonella henselae, and rickettsia felis) have been recognized in urban environments. other newly recognized pathogens (ehrlichia chaffeensis and ehrlichia phagocytophila in t ... | 2001 | 12653141 |
| rickettsia typhi infection in wild rodents from central spain. | when sera from 218 rodents captured in two provinces of central spain were tested, by indirect immunofluorescence, for antibodies to rickettsia typhi, 46 (21.1%) were found to be positive, at titres between 1:20 and 1:320. the seropositives included rodents of each of the five species collected: mus musculus, mus spretus, apodemus sylvaticus, rattus rattus and rattus norvegicus. rickettsia typhi infection appears to be common and widespread among the rodents of central spain. | 2003 | 12831526 |
| seroprevalence of rickettsial infection in commensal rodents and shrews trapped in the bangkok metropolitan area. | murine typhus and scrub typhus are important human rickettsial diseases in thailand. small mammals, including many species of rodents and shrews, serve as the reservoir host of rickettsial diseases. rickettsia typhi can be transmitted to humans by fleas causing murine typhus, while infection with orientia tsutsugamushi causing scrub typhus in humans is transmitted by chiggers. the prevalence of rickettsial infection depends on the geographic area. the seroprevalence of antibody to r. typhi and o ... | 2003 | 12924799 |
| seroepidemiological survey of rodents collected at a u.s. military installation, yongsan garrison, seoul, republic of korea. | a seroepidemiological study of selected rodent-borne diseases (hantavirus [seoul [seo] virus], scrub typhus [orientia tsutsugamushi], murine typhus [rickettsia typhi], and leptospirosis [leptospira interrogans]), as part of the u.s. military rodent surveillance and control program, was conducted from 2001 through 2005 at yongsan garrison, seoul, republic of korea. rodents were collected to determine the prevalence of rodent-borne diseases at a u.s. military installation in an urban environment. ... | 2007 | 17691691 |
| murine typhus: an unrecognized suburban vectorborne disease. | murine typhus, an acute febrile illness caused by rickettsia typhi, is distributed worldwide. mainly transmitted by the fleas of rodents, it is associated with cities and ports where urban rats (rattus rattus and rattus norvegicus) are abundant. in the united states, cases are concentrated in suburban areas of texas and california. contrary to the classic rat-flea-rat cycle, the most important reservoirs of infection in these areas are opossums and cats. the cat flea, ctenocephalides felis, has ... | 2008 | 18260783 |
| 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 ... | 2008 | 18412961 |
| [experimental study of the inoculative transmission of rickettsia typhi by gamasid mites (gamasidae) ornithonyssus bacoti]. | the authors' studies have established that the concentration of rickettsia typhi may increase about 100-fold in the infected ornithonyssus bacoti mites. at the time, when on feeding 20 to 200 adult mites on guinea-pigs and albino rats 4 to 36 days after inoculation, they did not transmit rickettsia typhi on blood sucking. | 2009 | 19566066 |
| 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 ... | 2010 | 21142968 |
| detection of rickettsia felis and rickettsia typhi and seasonal prevalence of fleas collected from small mammals at gyeonggi province in the republic of korea. | abstract fleas were collected from live-captured small mammals to identify flea-borne pathogens, host associations, and seasonal prevalence of flea species, as part of the 65th medical brigade rodent-borne disease surveillance program at 20 military installations and training sites, gyeonggi province, republic of korea, 2005-2007. a total of 1251 fleas were recovered from 2833 small mammals. apodemus agrarius, the striped field mouse, accounted for 93.1% (2,637/2,833) of all small mammals captur ... | 2011 | 21612536 |
| rats, cities, people, and pathogens: a systematic review and narrative synthesis of literature regarding the ecology of rat-associated zoonoses in urban centers. | urban norway and black rats (rattus norvegicus and rattus rattus) are the source of a number of pathogens responsible for significant human morbidity and mortality in cities around the world. these pathogens include zoonotic bacteria (leptospira interrogans, yersina pestis, rickettsia typhi, bartonella spp., streptobacillus moniliformis), viruses (seoul hantavirus), and parasites (angiostrongylus cantonensis). a more complete understanding of the ecology of these pathogens in people and rats is ... | 2013 | 23590323 |
| 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 ... | 2014 | 24445202 |
| an investigation of bartonella spp., rickettsia typhi, and seoul hantavirus in rats (rattus spp.) from an inner-city neighborhood of vancouver, canada: is pathogen presence a reflection of global and local rat population structure? | urban norway and black rats (rattus norvegicus and rattus rattus) are reservoirs for variety of zoonotic pathogens. many of these pathogens, including rickettsia typhi, bartonella spp., and seoul hantavirus (seov), are thought to be endemic in rat populations worldwide; however, past field research has found these organisms to be absent in certain rat populations. rats (rattus spp.) from an inner city neighborhood of vancouver, canada, were tested for exposure to and/or infection with seov and r ... | 2015 | 25629777 |
| prevalence and characteristics of escherichia coli and salmonella spp. in the feces of wild urban norway and black rats (rattus norvegicus and rattus rattus) from an inner-city neighborhood of vancouver, canada. | although rat feces are widely suspected to be a source of pathogenic bacteria, few investigators have studied fecal pathogens in rats. we investigated the prevalence and characteristics of escherichia coli and salmonella spp. in norway and black rats (rattus norvegicus and rattus rattus, respectively) from an urban neighborhood of vancouver, canada, collected september 2011-august 2012. colon content was cultured for e. coli and salmonella spp. and screened for the seven most-common enteropathog ... | 2015 | 25932669 |
| serologic evidence for rickettsia typhi and an ehrlichial agent in norway rats from baltimore, maryland, usa. | we screened serum from 90 norway rats trapped in east baltimore, maryland, usa, from april to november 2005 for antibodies against rickettsia typhi and ehrlichia chaffeensis. six rats had positive titers of > or = 1:64 against r. typhi and did not react with r. akari. in addition, four rats had cross-reactive antibodies with titers of > or = 1:64 against ehrlichia chaffeensis. sera from these rats also cross-reacted with anaplasma phagocytophilum or ehrlichia muris. our data indicate that the ag ... | 2006 | 16989563 |
| prevalence study of antibody to ratborne pathogens and other agents among patients using a free clinic in downtown los angeles. | norway rats (rattus norvegicus) are hosts for various microbes. homeless people who have contact with rats may be at risk of infection by them. the los angeles county department of health services initiated a seroepidemiologic study among patients who used a free clinic in downtown los angeles; 200 serum specimens obtained for other routine assays were tested for antibodies to ratborne pathogens and other agents. the seroprevalence of antibody to hepatitis e virus in this population was 13.6%; t ... | 2002 | 12447746 |
| 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 ... | 2002 | 12164301 |
| prevalence of antibodies to coxiella burnetti, rickettsia conorii, and rickettsia typhi in seven african countries. | the prevalences of antibodies reactive with coxiella burnetti, rickettsia conorii, and rickettsia typhi were determined by indirect fluorescent antibody testing of sera from seven african countries. the seroprevalences of antibodies reactive with c. burnetti and r. conorii in countries from north africa were similar to those reported from southern europe. in countries of sub-saharan africa, the seroprevalence of antibodies reactive with c. burnetti varied greatly; the generally higher figures fo ... | 1995 | 8589132 |
| 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 ... | 1994 | 7966170 |
| 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 ... | 1994 | 7893179 |
| experimental infection with rickettsia mooseri and antibody response of adult and newborn laboratory rats. | quantitative studies of selected features of peripherally induced rickettsia mooseri (= r. typhi) infection in rattus norvegicus-derived white laboratory rats revealed a unique association between microbe and amplifying vertebrate host which appears to be especially conducive to maintenance of the enzootic cycle. both adult and newborn (1-3 days old) rats were highly susceptible to percutaneous infection (id50 = approximately 1 organism), but neither showed signs of disease or died even when ino ... | 1984 | 6486291 |
| [immune animal organs from the viewpoint of culture]. | | 1965 | 4957016 |
| transmission of murine typhus rickettsiae by xenopsylla cheopis, with notes on experimental infection and effects of temperature. | in studies on experimental infection of rickettsia mooseri (= r. typhi) in xenopsylla cheopis and laboratory rats, it was found that 10 days after the infectious feeding, the fleas were voiding feces that were infective to rats upon inoculation. the feces remained infective for at least the duration of the experiment, and a quantity as small as 0.2 micrograms of feces would result in seroconversion of 67% of the rats upon inoculation. fleas were capable of transmitting the infection to rats as e ... | 1985 | 3923852 |
| newborn rats in the murine typhus enzootic infection cycle: studies on transplacental infection and passively acquired maternal antirickettsial antibodies. | this study focused attention on the newborn rat as a possible significant participant in the highly successful enzootic cycle of murine typhus. we examined the influence of maternal rickettsia typhi (r. mooseri) infection in rats on the offspring with respect to the possible vertical transmission of r. typhi and the passive transfer of maternal antirickettsial antibodies. transmission of r. typhi by rickettsemic pregnant rats did not occur either transplacentally during gestation to their fetuse ... | 1988 | 3142287 |
| 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. ... | 1987 | 3120611 |
| 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 ... | 2014 | 24820571 |
| rats as indicators of the presence and dispersal of six zoonotic microbial agents in cyprus, an island ecosystem: a seroepidemiological study. | a total of 622 rats (402 rattus norvegicus and 220 r. rattus frugivorus) were collected in 51 different areas in cyprus during 2000-2003 and used as indicators of the presence and dispersal of six zoonotic microbial agents. igg antibodies against rickettsia typhi (241/496, 48.6%), r. conorii (209/500, 41.8%), toxoplasma sp. (138/494, 27.9%), coxiella burnetti (63/494, 12.8%), bartonella henselae (52/494, 10.5%) and leishmania infantum (36/494, 7.3%) were detected by indirect immunofluorescence t ... | 2010 | 20870259 |
| detection of rickettsia typhi and seasonal prevalence of fleas collected from small mammals in the republic of korea. | fleas were collected from live-captured small mammals to identify potential flea-borne pathogens, seasonal prevalence of flea species, and host preference as part of the us military rodent-borne diseases surveillance program conducted at one us military installation and 10 military training sites, northern gyeonggi province, republic of korea. during 2003-04, 948 fleas (563 females and 385 males) were recovered from 2,742 small mammals (seven rodent and one insectivore species). apodemus agrariu ... | 2010 | 20090029 |
| a survey of zoonotic pathogens carried by norway rats in baltimore, maryland, usa. | norway rats (rattus norvegicus) carry several zoonotic pathogens and because rats and humans live in close proximity in urban environments, there exists potential for transmission. to identify zoonotic agents carried by rats in baltimore, maryland, usa, we live-trapped 201 rats during 2005-2006 and screened them for a panel of viruses, bacteria, and parasites. antibodies against seoul virus (57.7%), hepatitis e virus (hev, 73.5%), leptospira interrogans (65.3%), bartonella elizabethae (34.1%), a ... | 2007 | 17224086 |
| [intrapulmonary immunization against rickettsia mooseri and comparative evaluation of its effectiveness]. | | 1964 | 14198914 |