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Rickettsia felis is an obligate intracellular alpha-proteobacteria and the cause of flea-borne spotted fever (FBSF), an emerging zoonosis of global public health importance, for which dogs and cats have been implicated as potential mammalian reservoirs hosts. The purpose of this study was to determine the prevalence and associated risk factors for R. felis-like species in semi-domesticated cats and their fleas in aim of understanding public health risks posed by cats and their fleas in Bangkok, Thailand. Single whole blood samples (n = 432) and where observed, fleas (n = 234), were collected from cats from 53 temple communities in Bangkok. Fleas were morphologically and genetically identified to a species level. Cat blood and fleas were subjected to a spotted fever group (SFG)-specific PCR targeting the partial outer membrane protein B (ompB). Those that were positive, were further characterised using an R. felis-specific nested PCR targeting the partial citrate synthase A (gltA) gene. All fleas were identified as Ctenocephalides felis felis. In total SFG Rickettsiae were detected in the blood of 82/482 (17.01%) cats and 3/234 fleas (1.28%). DNA sequencing of the partial ompB characterised all positive amplicons from cat blood and their fleas as 100% identical to Rickettsia endosymbiont of Ctenocephalides felis orientis isolate (Rickettsia sp. genotype RF2125) and Rickettsia asemboensis (GenBank accession no. KP256362 and KY650699, respectively). The gltA gene targeting R. felis was successfully amplified from 12/82 PCR-positive cat blood samples and these clustered with 99% bootstrap support with isolates within the Rickettsia sp. genotype RF2125 clade. Cats that were permitted to roam freely inside monasteries were more likely to be infected with R. felis compared with cats confined indoors. The results suggest that cats in Thailand are potential mammalian reservoir hosts for Rickettsia sp. genotype RF2125.

The aims of this study were to assess the psocids that potentially carry Rickettsia and to characterize Rickettsia species. We collected booklice from dried fragments of Chinese medicinal herbs for retail. Species identification and Rickettsia detection were performed by using nondestructive DNA extraction method and PCR. Of the 224 booklice samples collected, the following species were identified: Liposcelis pearmani (50.89%), L. bostrychophila (25.89%) and L. entomophila (23.21%). Twenty-four samples were found to be positive for Rickettsia (10.71%, 24/224), and the number of Rickettsia-positive samples per species was as follows: L. pearmani (n = 10), L. bostrychophila (n = 8) and L. entomophila (n = 6). The phylogenetic tree revealed that the rickettsial agents found in booklice cluster along with Rickettsia felis belong to the spotted fever group (SFG). Mixed booklice contamination occurs in herbal fragments. The presence of Rickettsia-infected booklice suggests that there is a risk of louse-borne rickettsioses to humans in contact with herbs. These findings can contribute to the development of a disease control program that assists relevant practitioners and promotes public health.

Fleas are commonly recorded on stray as well as domestic dogs and cats in Hong Kong. Fleas can be a major cause of pruritus in dogs and cats and also vectors of potentially zoonotic bacteria in the genera Rickettsia and Bartonella. Morphological examination of 174 fleas from dogs and cats living in Hong Kong revealed only cat fleas (Ctenocephalides felis). Cytochrome c oxidase subunit 1 gene (cox1) genotyping of 20 randomly selected specimens, revealed three cox1 haplotypes (HK-h1 to HK-h3). The most common haplotype was HK-h1 with 17 specimens (17/20, 85%). HK-h1 was identical to cox1 sequences of fleas in Thailand and Fiji. HK-h1 and HK-h2 form a distinct cat flea cox1 clade previously recognized as the Clade 3. HK-h3 forms a new Clade 6. A multiplex Bartonella and Rickettsia real-time PCR of DNA from 20 C. felis found Bartonella and Rickettsia DNA in three (15%) and ten (50%) C. felis, respectively. DNA sequencing confirmed the presence of R. felis, B. clarridgeiae and Bartonella henselae. This is the first reported study of that kind in Hong Kong, and further work is required to expand the survey of companion animals in the geographical region. The sampling of fleas on domestic cats and dogs in Hong Kong revealed them to be exclusively infested by the cat flea and to be harbouring pathogens of zoonotic potential.

The cat flea (Ctenocephalides felis) is the most common flea species parasitising both domestic cats and dogs globally. Fleas are known vectors of zoonotic pathogens such as vector borne Rickettsia and Bartonella. This study compared cat fleas from domestic cats and dogs in New Zealand’s North and South Islands to Australian cat fleas, using the mitochondrial DNA (mtDNA) marker, cytochrome c oxidase subunit I and II (cox1, cox2). We assessed the prevalence of Rickettsia and Bartonella using genus specific multiplexed real-time PCR assays. Morphological identification confirmed that the cat flea (C. felis) is the most common flea in New Zealand. The examined fleas (n = 43) at cox1 locus revealed six closely related C. felis haplotypes (inter-haplotype distance 1.1%) across New Zealand. The New Zealand C. felis haplotypes were identical or near identical with haplotypes from southern Australia demonstrating common dispersal of haplotype lineage across both the geographical (Tasman Sea) and climate scale. New Zealand cat fleas carried Rickettsia felis (5.3%) and Bartonella clarridgeiae (18.4%). To understand the capability of C. felis to vector zoonotic pathogens, we determined flea cox1 and cox2 haplotype diversity with the tandem multiplexed real-time PCR and sequencing for Bartonella and Rickettsia. This enabled us to demonstrate highly similar cat fleas on cat and dog populations across Australia and New Zealand.

Rickettsia felis is an emerging zoonosis, causing flea-borne spotted fever (FBSF). Serological diagnosis is typically confounded by cross-reactivity with typhus group rickettsiae and prior to the development of specific serological methods, cases of FBSF in Australia were misdiagnosed.Patient sera tested between August 2010 and December 2013 and known to be seropositive to R. typhi by immunofluorescence antibody testing (IFAT) were subsequently retested against R. felis using an R. felis-specific IFAT. Sera of 49 patients were of a sufficient quality to be included in re-analysis. A classification of FBSF and murine typhus (MT) was attributed to fourteen and seven patients respectively, based on a minimum four-fold higher antibody titre to R. felis than to R. typhi and vice versa. Twenty-eight patients were classified as indeterminate for either R. felis or R. typhi (antibody titres within two-fold of one another).Historically, it is likely that Australian patients clinically ill with FBSF were misdiagnosed. It is important that medical practitioners consider FBSF as part of their differential diagnoses, and obtain relevant history with regard to patient's exposure to domestic pets and their fleas. Australian microbiology diagnostic laboratories should include serological testing for R. felis as part of the diagnostic panel for febrile diseases. Veterinarians are encouraged to increase their awareness of this emerging zoonosis and advocate flea control in pets.

Introduction Rickettsia felis is the causative agent of flea-borne spotted fever (FBSF), an emerging zoonosis. Although there is evidence of FBSF in Greece, fleas, the classic vectors of R. felis, have not been adequately studied. Thus, the aim of this study was to detect and characterize bacteria of genus Rickettsia and especially R. felis from common fleas parasitizing domestic cats and dogs in Greece and evaluate the efficiency of established molecular techniques. Materials and methods DNA of flea-pools (samples) by animal-host was investigated by quantitative real-time PCRs (qPCR), and 16S metagenomics (16S). Determination of Rickettsia spp., Rickettsia felis-like organisms (RFLOs), and R. felis was based on a combination of qPCRs targeting gltA and ompB genes, 16S automated metagenomics and manual comparison of 16S sequences for >99% similarity with the publicly available 16S R. felis GenBank sequences using the Basic Local Alignment Search Tool (BLAST>99). Information for the animal-hosts was available and statistically analyzed. Results Among 100 flea-pools, R. felis was detected in 14 samples with a combination of six, five and three assays in 10, two and two samples, respectively. The sensitivity of the assays for Rickettsia genus (16S, and genus specific qPCRs) ranged from 62.5% to 93.8% and the specificity from 65.0% to 100%. R. felis-targeting qPCRs for gltA and ompB demonstrated sensitivity and specificity of 92.9% and 100%, and 100.0% and 87.5%, respectively. 16S metagenomics using the assay software was not able to identify R. felis positive specimens, although manual BLAST>99 did identify the species, but demonstrated sensitivity of 92.9% and specificity of 65.0%. No association of the detection rate of Rickettsia genus or R. felis, with the epidemiological data collected, was identified. Conclusions These observations suggest the occurrence of R. felis in fleas from pets in Attica, Greece, but PCR and sequencing assays varied considerably in sensitivity and specificity and a consensus methodology for assigning the positivity status is required to be established.

Dogs and cats are important hosts and reservoirs of many viral, bacterial, protozoal, and helminthic pathogens transmitted by arthropods, including some of zoonotic concern. By sharing the same environment, these companion animals play an important role in the transmission of zoonotic pathogens to humans in various regions and socioeconomic contexts. While canine and feline vector-borne diseases (VBD) are of major concern in wealthy regions (e.g. Europe and North America), less attention has been received in developing countries such as those in Southeast Asia (SEA). This review provides summarized and updated information on canine and feline VBD with emphasis on those of zoonotic concern in SEA. Of these, zoonotic bacteria (i.e. Bartonella henselae, Bartonella clarridgeiae, and Rickettsia felis) and filarial nematodes (i.e. Brugia malayi, Dirofilaria repens, and Dirofilaria immitis) stand out as the most important in veterinary and human medicine. Additionally, the recent finding of Leishmania infantum in dogs in SEA raised more concerns about the spreading of this zoonotic agent in this region. Further epidemiological surveys, especially in countries with extremely scant information such as Cambodia, Laos, Myanmar, and Timor-Leste are advocated. Additionally, effective control measures of canine and feline VBD as well as their arthropod vectors should be simultaneously performed for the management of zoonotic infections.

The cat flea (Ctenocephalides felis) is the most common flea species parasitising both domestic cats and dogs globally. Fleas are known vectors of zoonotic pathogens such as vector-borne Rickettsia spp. and Bartonella spp. and could theoretically transmit Coxiella burnetii, the causative agent of Q fever. A total of 107 fleas were collected from 21 cats and 14 dogs in veterinary clinics, a feline rescue organisation and a grooming salon in New South Wales, Australia, to undergo PCR detection of Bartonella spp., Rickettsia spp. and C. burnetii DNA. Morphological identification confirmed that the cat flea (C. felis) is the most common flea in New South Wales, Australia, with only a single stick fast flea, Echidnophaga gallinacea recorded. The examined fleas (n = 35) at the cox1 locus revealed five closely related C. felis haplotypes (inter-haplotype distance

From July 2015 to December 2016, the presence of rickettsial pathogens was investigated for 414 patients with unknown fever in eight places in all the divisions of Bangladesh. Rickettsia felis was identified in blood samples from all the regions (overall detection rate, 19.6%), suggesting nationwide prevalence of R. felis infections.

Cat fleas (Ctenocephalides felis) are the most commonly recognised ectoparasites of domestic pets globally and are frequently implicated in the transmission of a variety of zoonotic vector-borne pathogens. The aim of the present study was to investigate the morphological and molecular identity of fleas parasitising cats and dogs in Northern Laos and screen them for a range of bacterial pathogens. Fleas (n = 120) were collected from dogs and cats and morphologically identified as Ctenocephalides felis (115/120), Ctenocephalides orientis (4/120) and Pulex irritans (1/120). Molecular barcoding using the cytochrome c oxidase subunit I gene (cox1) was used to confirmed species identity of 21 selected fleas. The cat flea (C. felis) was the most dominant flea identified. Rickettsia and Bartonella spp. DNA was detected in 21/21 and 7/21 samples, respectively, via a multiplex real-time PCR targeting gltA and ssrA. Sequencing of the seven Bartonella-positive samples and ten Rickettsia-positive samples revealed Bartonella clarridgeiae, Bartonella rochalimae, Rickettsia felis and Rickettsia sp. genotype RF2125 DNA. Anaplasma platys DNA was detected in a single C. felis after 20 of the 21 DNA samples were screened using a commercial PCR panel for vector-borne pathogens. The detection of a range of bacterial pathogens in fleas from owned cats and dogs in Northern Laos provides further evidence to the importance of these ectoparasites as vectors of zoonotic diseases in the region.

Genome sequences of 36 Rickettsia and Orientia were analyzed using Formal Order Analysis (FOA). This approach takes into account arrangement of nucleotides in each sequence. A numerical characteristic, the average distance (remoteness) - "g" was used to compare of genomes. Our results corroborated previous separation of three groups within the genus Rickettsia, including typhus group, classic spotted fever group, and the ancestral group and Orientia as a separate genus. Rickettsia felis URRWXCal2 and R. akari Hartford were not in the same group based on FOA, therefore designation of a so-called transitional Rickettsia group could not be confirmed with this approach.

International audience; Little is known about the epidemiology of zoonotic diseases in American Samoa (Pacific). A review of literature did not identify any published information on human Rickettsia spp., Bartonella spp., Ehrlichia spp. or Coxiella burnetii infections in this country. To determine the presence of these diseases, we conducted a serosurvey of American Samoans. The presence of immunoglobulin G antibodies against Rickettsia felis, Rickettsia typhi, Rickettsia conorii, C. burnetii, Bartonella henselae, Bartonella quintana, and Ehrlichia chaffeensis was evaluated by indirect immunofluorescence assay in sera from 197 American Samoan adults. None of the samples had antibodies at a significant level against Rickettsia spp., Bartonella spp., Ehrlichia spp. or C. burnetii (seroprevalence 0%; one-tailed 95% CI 0-1.86%). We cannot conclude that these pathogens are absent in American Samoa but, if present, their prevalence is probably very low. Q fever has been reported worldwide except in New Zealand and French Polynesia; these new data suggest that the prevalence of Q fever is likely to be very low in the Pacific Islands. (C) 2016 Elsevier GmbH. All rights reserved.

Certain vector-borne organisms serve as etiological agents of equine disease. After previously identifying a new Ehrlichia species in horses from Merida, we aimed to determine the infection frequency and screen for a wide range of vector-borne organisms from 93 tick-exposed, Ehrlichia seropositive horses in this region. PCR assays were performed to identify infection by organisms within the following genera: Anaplasma, Babesia, Bartonella, Ehrlichia, Leishmania, Mycoplasma, Neorickettsia, Rickettsia and Theileria. Overall, 90/93 horses (96.8%) were infected with one or more vector-borne organisms. Ninety (96.8%) horses were infected with Theileria equi and 21 (26.8%) with Babesia caballi. Nine (9.7%) horses were infected with the novel Ehrlichia species previously designated H7, reported in horses from Nicaragua and Brazil. Two horses (2.2%) were infected with Rickettsia felis. Anaplasma, Bartonella, Leishmania, Mycoplasma, or Neorickettsia species DNA was not amplified from any horse. Ticks collected from horses infected with vector-borne organisms were identified as Amblyomma cajennense sensu lato and Dermacentor nitens. Horses in Merida are infected by a range of vector-borne organisms, including B. caballi, T. equi, Ehrlichia species H7, and R. felis. To the authors’ knowledge, this constitutes the first report of molecular detection of R. felis in horses.

Flea infestations are common in Thailand, but little is known about the flea-borne infections. Fifty flea pools and 153 blood samples were collected from client-owned cats between June and August 2009 from veterinary hospitals in Bangkok, Thailand. Total DNA was extracted from all samples, and then assessed by conventional PCR assays. The prevalence rates of Bartonella spp. in blood and flea samples were 17% and 32%, respectively, with DNA of Bartonella henselae and Bartonella clarridgeiae being amplified most commonly. Bartonella koehlerae DNA was amplified for the first time in Thailand. Hemoplasma DNA was amplified from 23% and 34% of blood samples and flea pools, respectively, with 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis being detected most frequently. All samples were negative for Rickettsia felis. Prevalence rate of B. henselae DNA was increased 6.9 times in cats with flea infestation. Cats administered flea control products were 4.2 times less likely to be Bartonella-infected.

Hedgehogs have become a popular pet despite their potential role in zoonotic disease transmission. We conducted an entomological study in a mountainous region of northeast Algeria in which we collected 387 fleas (Archeopsylla erinacei) and 342 ticks (Rhipicephalus sanguineus and Haemaphysalis erinacei) from Paraechinus aethiopicus and Atelerix algirus hedgehogs. Of the hedgehogs sampled, 77.7% and 91% were infested with fleas and ticks, respectively. Significantly more ticks and fleas were collected from A. algirus than from P. aethiopicus. Rickettsia felis was detected in 95.5% of fleas and R. massiliae was detected in 6.25% of Rh. sanguineus ticks by molecular tools. A new Rickettsia species of the spotted fever group was detected in 11.25% of Rh. sanguineus and in 77% of H. erinacei ticks. Overall, we show that hedgehogs can act as hosts for ectoparasites infected with several rickettsial agents. These data justify a more detailed investigation of animal reservoirs for Rickettsiae.

The aim of our study was to detect the presence of Rickettsia spp. and Bartonella spp. in ticks and fleas collected from red foxes (Vulpes vulpes) in southeastern France during 2008. Using a genus-specific quantitative PCR (qPCR) assay, which was followed by a species-specific qPCR assay for the positive samples, 45.2% (33/73) of ticks (Rhipicephalus turanicus) were found to be infected with Rickettsia massiliae. 10.5% (2/19) of the fleas (Archaeopsylla erinacei) collected in the study tested positive for Rickettsia jells. A genus-specific qPCR assay did not reveal any Bartonella species in any of the ticks or fleas collected. The role of red foxes in the epidemiology of spotted fever caused by Rickettsiae species requires further investigation.

Rickettsia spp. are zoonotic pathogens and mainly transmitted by various arthropod vectors, such as fleas, ticks, and lice. Previous epidemiological studies indicated that ectoparasites infested on dogs or cats may be infected by Rickettsia spp., and transmit them to human beings accidentally. In this study, the prevalence of Rickettsia infection was evaluated using fleas and ticks from stray dogs and cats in Taiwan. A total of 158 pools made by 451 cat fleas (Ctenocephalides felis) from 37 dogs and 4 cats were used for analysis. Besides, 386 Rhipicephalus ticks collected from the other 62 stray dogs were included in this study. Nymphal and adult ticks were individually analyzed but larvae were separated into 21 pools for molecular detection. Partial sequencing analysis of the gltA gene was applied for Rickettsia identification. The results showed that 44.3% (70/158) of the cat flea pools were harboring Rickettsia DNA. Although 6.9% (13/187) of adult ticks were infected with Rickettsia, neither larval pools nor nymphal ticks were found to contain Rickettsia DNA. According to the results of sequencing analyses, all Rickettsia PCR-positive cat flea pools were infected with R. felis, and all Rickettsia PCR-positive adult ticks were infected with R. rhipicephali. The results of this study demonstrated that C. felis but not Rhipicephlus sanguineus (the brown dog tick) and Rh. haemaphysaloides collected from stray animals in Taiwan could be infected the zoonotic pathogen R. felis. Moreover, R. rhipicephali was only identified in adult stage of Rhipicephalus sanguineus and Rh. haemaphysaloides.

Summary Objective The aim of this work was to evaluate the prevalence of past infection due to Rickettsia typhi and Rickettsia conorii in the Canary Islands (Spain). Methods A representative sample of the population of the seven islands, formed of 662 people aged between 5 and 75 years (368 females, 294 males), was analyzed. Epidemiological data were obtained by direct survey. The detection of serum IgG antibodies against both microorganisms was based on an indirect immunofluorescence test, considered positive if the titers were ≥1/80. Results Of the analyzed population 3.9% had IgG antibodies against R. typhi and 4.4% against R. conorii . Out of these positive samples, only three were positive for both species. The seroprevalence was similar in both sexes. Positive results were found in all age groups, but a higher rate was noticed in those aged 46 years and older ( p R. typhi was found to be more prevalent in rural areas of all islands, as well as in farmers. Conclusions Our results confirm the presence of antibodies against the causative agents of murine typhus and Mediterranean spotted fever in the Canary Islands. Indirect data suggest that the detection of antibodies to R. conorii might be due to a cross-reaction between these species.

A wide range of blood-sucking arthropods have either been confirmed or are suspected as important vectors in Bartonella transmission to mammals, including humans. Overall, it appears that the diversity of Bartonella species DNA identified in ectoparasites is much broader than the species detected in their mammalian hosts, suggesting a mechanism of adaptation of Bartonella species to their host-vector ecosystem. However, these mechanisms leading to the fitness between the vectors and their hosts still need to be investigated.

The present research evaluated the presence of Rickettsia spp. on ectoparasites of horses and dogs (using PCR techniques), and their sera (using immunofluorescence assay) in El Valle de Antón town in Panama. A total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks Rhipicephalus sanguineus, Amblyomma ovale, Amblyomma oblongoguttatum, and the flea Ctenocephalides felis), and two tick species on horses (Amblyomma cajennense and Dermacentor nitens). DNA of Rickettsia amblyommii was found in pools of A. cajennense, D. nitens, and R. sanguineus, while Rickettsia felis was detected in C. felis pools. Overall, 70% (14/20) and 65% (13/20) of the horses and dogs, respectively, were seroreactive (titer ≥ 64) to spotted fever group rickettsiae. Sera from six dogs and five horses reacted to R. amblyommii antigens with titers at least four-fold higher than those for the other antigens tested (Rickettsia bellii, Rickettsia parkeri, Rickettsia rhipicephali, R. felis, and R. rickettsii). These serological results, coupled with our molecular findings, suggest that these dogs and horses were infected by Rickettsia amblyommii. More studies need to be realized afford to identify the Rickettsia species responsible for other serological and molecular positive results, and their ecological importance.

Rickettsia felis infection usually is a mild-to-moderate illness characterized by general signs and symptoms. Generally, patients do not require hospitalization. However, we detected 2 severe infections with R. felis. Our findings support the importance of R. felis infection as a potentially severe illness in humans.

Rickettsia typhi and Rickettsia felis are the etiologic agents of murine typhus and flea-borne spotted fever, respectively. We have constructed two quantitative real-time polymerase chain reaction (qPCR) assays to detect these pathogenic rickettsiae. The qPCR assays were developed utilizing unique sequences of the R. typhi and R. felis outer membrane protein B genes (ompB) to design the specific primers and molecular beacon probes. The assays were found to be species-specific and did not yield false-positive reactions with nucleic acid from other rickettsiae, orientiae, neorickettsiae or unrelated bacteria. In addition, the assays were sensitive enough to detect three target sequence copies per reaction and were capable of detecting R. typhi and R. felis nucleic acid in the cat flea, Ctenocephalides felis. These results demonstrate that two sensitive and specific qPCR assays have been successfully developed to detect and enumerate R. typhi and R. felis.

The carriage of Bartonella, Rickettsia felis and haemoplasma species was investigated in cat fleas (Ctenocephalides felis) collected from 121 cats and dogs in the United Kingdom. DNA extracted from fleas was analysed using genus and species-specific PCR and amplicons were characterised using DNA sequencing. Fifty percent of flea samples were PCR positive for at least one pathogen. Twenty one percent were positive for R. felis, 17% for Bartonella henselae, 40% for haemoplasma species and 20% were infected with more than one of the pathogen species studied. It is clear from the results in this study that companion cats and dogs are commonly infested with Ct. felis carrying bacterial pathogens of significance to human and animal health. These findings raise the possibility that Ct. felis found on dogs and cats are a potential source of infection with such pathogens for humans.

Background: Fever caused by Rickettsia felis was recently shown to play an important role in infectious diseases morbidity in sub-Saharan Africa. Eschar biopsy has been repeatedly shown to be very useful for the detection of rickettsial DNA in patients. To evade the biopsy, a good alternative may be the examination of swabs from skin lesions in rickettsiosis patients. Rickettsial DNA may be present in the crusts and fluids of the eschars, even after the initiation of treatment and in cases for which serum (even convalescent) remains negative against rickettsial antigens To clarify the clinical symptoms of R. felis infection,we collected 68 cotton swabs from fever-associated eschars in four different regions of Senegal. Methods & Materials: The criteria for inclusion in the study were as follows: (1) the presence of fever (axillary temperature >37.5 ◦C) as the primary symptom, and (2) the presence of eschar(s) on the skin of the patient. Eschars (tache noire) in our patientswere identified as single or several (grouped) local skin lesions coated by a coagulated crust or slough that developed without anterior anamnesticallyevident trauma.TheDNAextracted fromthese samples, as well as DNA from negative controls (healthy skin swabs fromSenegal andFrance),was tested for thepresenceof pathogenic bacteria. Results: In 5/68 of eschar samples (7.4%), we have identified DNA from R. felis. In 49/68 (72.1%), we found DNA from Staphylococcus aureus; in 35/68 (51.5%), Streptococcus pyogenes; and in 4/68 (5.9%), Streptococcus pneumoniae. In 34 cases, S. aureus was found together with S. pyogenes. DNA from R. felis was also found in swabs from the skin of the healthy Senegalese villagers (3/60, 5%), but not from French urbanites. Conclusion: The presence of DNA from S. aureus and S. pyogenes was significantly associated with the presence of eschars in febrile patients compared to the healthy skin from the control group.When the two negative control groupswere compared, only thepresenceof S. aureusDNAwassignificantlyhigher inSenegalese villagers. Finally, we confirmed that Senegal is an endemic region for R. felis, which is found in both eschars and healthy skin swabs.

Rickettsia typhi is the aetiological agent of murine typhus (MT). This disease is often acute and mild, although some fatal cases have been observed [1]. In Spain, clinical cases and serological evidence of exposure to R. typhi in humans have been described [2,3]. In the past, MT has been associated with rodents and rat fleas. Later, a peridomestic animal cycle involving cats, dogs, opossums and their fleas [1] was described. In Spain, R. typhi seropositivity has been shown in dogs [4] from the central region. Rickettsia felis, transmitted by fleas, produces flea-borne spotted fever, a clinical syndrome indistinguishable from MT. Serological evidence of R. felis infection in humans has been observed in Spain [2,3]. R. felis has been detected in fleas commonly found on domestic cats and dogs in Spain [5]. Prevention of these infections depends on recognition of routes of transmission, risk factors for infection, and reservoirs. The aim of this study was to determine the prevalence of both rickettsiae in dog populations from the north-east of Spain.

Brazilian spotted fever (BSF) caused by Rickettsia rickettsii is transmitted to humans by Amblyomma tick species occurring mainly in southeastern regions of the country. The disease is similar to the North American Rocky Mountain spotted fever and without an adequate and prompt treatment it can be fatal. In the last years, the number of BSF cases has increased in the State of Rio de Janeiro. Epidemiologic data on vectors and hosts are lacking. Recently, the first BSF fatal case was registered in the Barra Mansa municipality. Targeting the adoption of the adequate rickettsiosis control strategy we developed an epidemiological study, using immunological and molecular techniques, to detect Rickettsia species in potential vectors and hosts of this new BSF focus.

Rickettsial Zoonoses Branch, National Center for Zoonotic, Vector-Borne and Enteric Diseases, Centers for Disease Control and Prevention, Atlanta, GA, California Department of Public Health, VectorBorne Disease Section, Ontario, CA, Orange County Vector Control District, Garden Grove, CA, USA, Long Beach Department of Health and Human Services, Vector Management Program, Long Beach, CA, USA, and Long Beach Department of Health and Human Services, Animal Control Division, Long Beach, CA, USA

Summary Three patients with fever, exanthem, headache, and central-nervous-system involvement were diagnosed with Rickettsia felis infection by specific PCR of blood or skin and seroconversion to surrogate Rickettsia antigens. Although R felis's relationship to other Rickettsia species is known and the pathogenic potential of this clade is well documented, R felis's role as a pathogen has not been fully understood.