Rickettsia rickettsii is the causative agent of Brazilian spotted fever (BSF), for which humans and dogs are both susceptible. Dogs are sentinels in serological surveys, however, canine disease is rarely reported. Therefore, we aimed to evaluate natural infection by spotted fever group (SFG) Rickettsia spp. in dogs and ticks collected from domiciles close to forest fragments, featuring domestic-wildlife interface areas. Samples from 115 dogs and 135 ixodids were assessed by polymerase chain reactions (PCR) targeting the gltA gene for Rickettsia spp. and the ompA gene for the SFG rickettsial species. One dog (0.87%; 1/115) was positive for R. rickettsii. This dog presented nonspecific laboratory and clinical abnormalities (thrombocytopenia, hyperproteinemia, lymph node enlargement, emaciation, anorexia, and lethargy). Rickettsia parkeri was identified in 2.96% (4/135) of the ticks (Amblyomma sculptum, A. aureolatum, and Rhipicephalus sanguineus). This study confirmed the presence of SFG bacteria in non-endemic and preserved locations, where domestic and wild populations interact. We reinforce the fact that the dog is susceptible to natural R. rickettsii infection. Although this is a rare finding, preventive measures should be taken against BSF in the studied areas. Finally, R. parkeri infection is possibly being demonstrated in A. sculptum for the first time.

• MeSH
• klíšťata mikrobiologie   MeSH
• nemoci psů diagnóza   mikrobiologie   MeSH
• polymerázová řetězová reakce MeSH
• protilátky bakteriální krev   MeSH
• psi MeSH
• Rickettsia klasifikace   genetika   izolace a purifikace   MeSH
• skvrnité horečky diagnóza   mikrobiologie   veterinární   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Brazílie MeSH

BACKGROUND: Rickettsialpox is a febrile illness caused by the mite-borne pathogen Rickettsia akari. Several cases of this disease are reported worldwide annually. Nevertheless, the relationship between the immunogenicity of R. akari and disease development is still poorly understood. Thus, misdiagnosis is frequent. Our study is aiming to identify immunogenic proteins that may improve disease recognition and enhance subsequent treatment. To achieve this goal, two proteomics methodologies were applied, followed by immunoblot confirmation. RESULTS: Three hundred and sixteen unique proteins were identified in the whole-cell extract of R. akari. The most represented protein groups were found to be those involved in translation, post-translational modifications, energy production, and cell wall development. A significant number of proteins belonged to amino acid transport and intracellular trafficking. Also, some proteins affecting the virulence were detected. In silico analysis of membrane enriched proteins revealed 25 putative outer membrane proteins containing beta-barrel structure and 11 proteins having a secretion signal peptide sequence. Using rabbit and human sera, various immunoreactive proteins were identified from which the 44 kDa uncharacterized protein (A8GP63) has demonstrated a unique detection capability. It positively distinguished the sera of patients with Rickettsialpox from other rickettsiae positive human sera. CONCLUSION: Our proteomic analysis certainly contributed to the lack of knowledge of R. akari pathogenesis. The result obtained may also serve as a guideline for a more accurate diagnosis of rickettsial diseases. The identified 44 kDa uncharacterized protein can be certainly used as a unique marker of rickettsialpox or as a target molecule for the development of more effective treatment.

• MeSH
• chromatografie kapalinová MeSH
• králíci MeSH
• lidé MeSH
• molekulární modely MeSH
• molekulová hmotnost MeSH
• proteiny vnější bakteriální membrány chemie   imunologie   metabolismus   MeSH
• proteomika metody   MeSH
• protilátky bakteriální krev   MeSH
• Rickettsia akari imunologie   izolace a purifikace   metabolismus   MeSH
• sekundární struktura proteinů MeSH
• skvrnité horečky diagnóza   imunologie   MeSH
• tandemová hmotnostní spektrometrie MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In the last two decades, the advent of molecular methods has revealed a remarkable diversity of rickettsiae (Rickettsiales: Rickettsiaceae) in invertebrates. Several species of these obligate intracellular bacteria are known to cause human infections, hence more attention has been directed towards human-biting ectoparasites. A spotted fever group Rickettsia sp. was previously detected in Ixodes lividus ticks (Ixodidae) associated with sand martins (Hirundinidae: Riparia riparia). In order to identify whether this rickettsia varies among isolated tick populations, a total of 1758 I. lividus ticks and five Ixodes ricinus ticks (Ixodidae) were collected in the Czech Republic and 148 I. lividus ticks were collected in Belgium, from nests of sand martins, European bee-eaters (Meropidae: Merops apiaster), Eurasian tree sparrows (Passeridae: Passer montanus), and from captured sand martins. We screened 165 and 78 I. lividus ticks (from the Czech Republic and Belgium, respectively) and all five I. ricinus ticks for the presence of rickettsial DNA. Only I. lividus samples were positive for Rickettsia vini, a spotted fever group rickettsia that commonly infects the tree-hole tick Ixodes arboricola (Ixodidae). Maximum likelihood analysis of the rickettsial sequences showed that the most closely related organism to R. vini corresponds to an uncharacterized rickettsia detected in Argas lagenoplastis (Argasidae), a nidicolous soft tick of the fairy martin (Hirundinidae: Petrochelidon ariel) in Australia. The observed variability of R. vini sequences from isolated tick populations was low; all 85 sequenced samples were identical to each other in five out of six partial rickettsial genes, except for the sca4 sequence (99.9% identity, 808/809 nt) that differed in I. lividus ticks from two sampling sites in the Czech Republic.

• MeSH
• Argasidae mikrobiologie   MeSH
• DNA bakterií genetika   MeSH
• fylogeneze MeSH
• infestace klíšťaty epidemiologie   veterinární   MeSH
• klíště mikrobiologie   MeSH
• koevoluce genetika   MeSH
• lidé MeSH
• nemoci ptáků mikrobiologie   MeSH
• nymfa MeSH
• pravděpodobnostní funkce MeSH
• ptáci parazitologie   MeSH
• Rickettsia klasifikace   genetika   izolace a purifikace   MeSH
• rickettsiové infekce epidemiologie   mikrobiologie   veterinární   MeSH
• skvrnité horečky epidemiologie   mikrobiologie   veterinární   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Belgie epidemiologie   MeSH
• Česká republika epidemiologie   MeSH

• MeSH
• diferenciální diagnóza MeSH
• erythema chronicum migrans MeSH
• klíšťová encefalitida komplikace   prevence a kontrola   MeSH
• lidé MeSH
• lymeská nemoc diagnóza   farmakoterapie   komplikace   MeSH
• lymská neuroborelióza MeSH
• nemoci přenášené klíšťaty * diagnóza   klasifikace   MeSH
• rickettsiové infekce MeSH
• skvrnité horečky MeSH
• virové vakcíny terapeutické užití   MeSH
• Check Tag
• lidé MeSH

Tick-borne diseases have become a world health concern, emerging with increasing incidence in recent decades. Spotted fever group (SFG) rickettsiae are tick-borne pathogens recognized as important agents of human tick-borne diseases worldwide. In this study, 88 adult ticks from the species Hyalomma anatolicum, Rhipicephalus annulatus, Rh. bursa, Rh. sanguineus sensu lato, and Rh. turanicus, were collected from farm ruminants in Lebanon, and SFG rickettsiae were molecularly identified and characterized in these ticks. The screening showed a prevalence of 68% for Rickettsia spp., including the species R. aeschlimannii, R. africae, R. massiliae and Candidatus R. barbariae, the latter considered an emerging member of the SFG rickettsiae. These findings contribute to a better knowledge of the distribution of these pathogens and demonstrate that SFG rickettsiae with public health relevance are found in ticks collected in Lebanon, where the widespread distribution of tick vectors and possible livestock animal hosts in contact with humans may favor transmission to humans. Few reports exist for some of the tick species identified here as being infected with SFG Rickettsia. Some of these tick species are proven vectors of the hosted rickettsiae, although this information is unknown for other of these species. Therefore, these results suggested further investigation on the vector competence of the tick species with unknown role in transmission of some of the pathogens identified in this study.

• MeSH
• farmy MeSH
• fylogeneze MeSH
• Ixodidae mikrobiologie   MeSH
• koně MeSH
• kozy MeSH
• nemoci koní epidemiologie   mikrobiologie   MeSH
• nemoci koz epidemiologie   mikrobiologie   MeSH
• nemoci ovcí epidemiologie   mikrobiologie   MeSH
• nemoci skotu epidemiologie   mikrobiologie   MeSH
• ovce MeSH
• prevalence MeSH
• Rickettsia klasifikace   fyziologie   MeSH
• sekvenční analýza DNA MeSH
• skot MeSH
• skvrnité horečky epidemiologie   mikrobiologie   veterinární   MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Libanon epidemiologie   MeSH

BACKGROUND: Tick-borne rickettsial diseases are caused by pathogens acquired from hard ticks. In particular, Rickettsia slovaca, a zoonotic infectious bacterium causing tick-borne lymphadenopathy (TIBOLA), is transmitted by the vectors Dermacentor spp. that can be found all over Europe. Although recent studies point out the extreme complexity of bacteria-induced effects in these blood-feeding vectors, the knowledge of individual molecules involved in the preservation and transmission of the pathogen is still limited. System biology tools, including proteomics, may contribute greatly to the understanding of pathogen-tick-host interactions. METHODS: Herein, we performed a comparative proteomics study of the tick vector Dermacentor reticulatus that was experimentally infected with the endosymbiotic bacterium R. slovaca. Rickettsia-free ticks, collected in the southern region of Slovakia, were infected with the bacterium by a capillary tube-feeding system, and the dynamics of infection was assessed by quantitative PCR method after 5, 10, 15 and 27 days. RESULTS: At the stage of controlled proliferation (at 27 dpi), 33 (from 481 profiled) differentially abundant protein spots were detected on a two-dimensional gel. From the aforementioned protein spots, 21 were successfully identified by tandem mass spectrometry. CONCLUSIONS: Although a few discovered proteins were described as having structural or housekeeping functions, the vast majority of the affected proteins were suggested to be essential for tick attachment and feeding on the host, host immune system evasion and defensive response modulation to ensure successful pathogen transmission.

• MeSH
• Dermacentor genetika   mikrobiologie   MeSH
• DNA bakterií MeSH
• infekce přenášené vektorem MeSH
• nemoci přenášené klíšťaty mikrobiologie   přenos   MeSH
• polymerázová řetězová reakce MeSH
• proteomika * MeSH
• Rickettsia genetika   patogenita   MeSH
• rickettsiové infekce přenos   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Geografické názvy
• Slovenská republika MeSH