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1.
Rev. bras. parasitol. vet ; 29(1): e018019, 2020. tab, graf
Article Dans Anglais | LILACS | ID: biblio-1058020

Résumé

Abstract The aim of the present study was to detect Cercopithifilaria bainae and other tick-borne pathogens and to perform molecular characterization of the tick Rhipicephalus sanguineus s.l. collected from dogs. Ticks (n = 432, including 8 larvae, 59 nymphs, and 365 adults) were sampled from domiciled dogs (n = 73) living in Campo Grande, Mato Grosso do Sul (Midwest Brazil). All ticks were morphologically identified as R. sanguineus. Genomic DNA was extracted in pools (three to five ticks per animal) and was used for definition of R. sanguineus haplotypes (based on 16S rRNA analysis) and pathogen identification (Cercopithifilaria sp., Ehrlichia canis, Anaplasma platys, Hepatozoon canis, Babesia vogeli and Rickettsia spp.). Rhipicephal us sanguineus specimens were identified as haplotypes A and B. DNA of Cercopithifilaria bainae (43.83%; 32/73), Ehrlichia canis (24.65%; 18/73), Anaplasma platys (19.17%; 14/73), and Hepatozoon canis (5.47%; 4/73) was detected. The identity of pathogens was confirmed by DNA sequence analysis. The present study confirms the presence of haplotypes A and B of R. sanguineus in the state of Mato Grosso do Sul and its importance as a vector of several pathogens of veterinary concern. Finally, this is the first report to identify C. bainae in ticks in the Midwestern region of Brazil.


Resumo O objetivo do presente estudo foi detectar Cercopithifilaria bainae e outros patógenos transmitidos por carrapatos e realizar a caracterização molecular do carrapato Rhipicephalus sanguineus s.l. coletado em cães. Carrapatos (n = 432, incluindo 8 larvas, 59 ninfas e 365 adultos) foram amostrados de cães domiciliados (n = 73) residentes no município de Campo Grande, Mato Grosso do Sul (centro-oeste do Brasil). Todos os carrapatos foram identificados morfologicamente como R. sanguineus. O DNA genômico foi extraído em pools (três a cinco carrapatos por animal), seguido pela definição de haplótipos (com base no gene 16S rRNA) e pela investigação de patógenos (Cercopithifilaria sp., Ehrlichia canis, Anaplasma platys, Hepatozoon canis, Babesia vogeli e Rickettsia spp.). Os espécimes coletados foram identificados como haplótipos A e B de R. sanguineus. Foram detectados DNA de Cercopithifilaria bainae (43,83%; 32/73), Ehrlichia canis (24,65%; 18/73), Anaplasma platys (19,17%; 14/73) e Hepatozoon canis (5,47%; 4/73). A identidade dos patógenos foi confirmada por análise de sequência de DNA. O presente estudo confirma a circulação dos haplótipos A e B de R. sanguineus no estado de Mato Grosso do Sul e sua importância como vetor de vários patógenos de interesse veterinário. Finalmente, este é o primeiro relato de C. bainae em carrapatos na região centro-oeste do Brasil.


Sujets)
Animaux , Vecteurs arachnides/parasitologie , Rhipicephalus sanguineus/parasitologie , Chiens/parasitologie , Rickettsia/isolement et purification , Rickettsia/génétique , Babesia/isolement et purification , Babesia/génétique , Brésil , ARN ribosomique 16S/génétique , Eucoccidiida/isolement et purification , Eucoccidiida/génétique , Ehrlichia canis/isolement et purification , Ehrlichia canis/génétique , Anaplasma/isolement et purification , Anaplasma/génétique
2.
Biomédica (Bogotá) ; 37(supl.2): 208-214, jul.-set. 2017. tab, graf
Article Dans Espagnol | LILACS | ID: biblio-888537

Résumé

Resumen Introducción. En estudios previos se detectó la presencia de Leishmania infantum en Rhipicephalus sanguineus, lo cual planteaba la posibilidad de que R. sanguineus transmitiera la leishmaniasis a una variedad de huéspedes. Objetivo. Identificar Leishmania (Viannia) spp. en garrapatas recolectadas en animales silvestres de una zona endémica para leishmaniasis. Materiales y métodos. Se hicieron 81 extracciones individuales de ADN en las garrapatas recogidas de tres tapires o dantas (Tapirus terrestres) y tres pecaríes de collar (Pecari tajacu) cazados en Madre de Dios, Perú. Las garrapatas recolectadas se identificaron taxonómicamente y se prepararon para la identificación del cinetoblasto (kDNA) de Leishmania (Viannia) spp. mediante reacción en cadena de la polimerasa (PCR), así como de la especie de Leishmania mediante PCR de fusión de alta resolución (High Resolution Melt, HRM). Resultados. Se detectó el kDNA de Leishmania (V) spp. en tres garrapatas silvestres de R. (Boophilus) microplus, Canestrini, 1888, recolectadas en un pecarí de collar cazado en la selva de Madre de Dios. El análisis mediante HRM-PCR evidenció que una de las muestras positivas de kDNA tenía una curva compatible con L. (V) guyanensis. Conclusión. Los resultados evidenciaron la presencia de ADN de L. (V) guyanensis en R. (Boophilus) microplus, probablemente adquirida después de picar al pecarí. Es importante hacer nuevos estudios para aclarar la participación de R. (Boophilus) microplus en la transmisión de la leishmaniasis.


Abstract Introduction: Previous studies identified the presence of Leishmania infantum in Rhipicephalus sanguineus and indicated the possibility that it could transmit leishmaniasis to a variety of hosts. Objective: To identify parasites of Leishmania (Viannia) spp. in ticks collected from wild animals in an endemic area for leishmaniasis. Materials and methods: We performed 81 individual DNA extractions from ticks collected from three Tapirus terrestris and three Pecari tajacu in Madre de Dios, Perú. Ticks were taxonomically identified and they were subsequently prepared to identify Leishmania (Viannia) spp. kDNA by PCR and the species of Leishmania by HRM-PCR. Results: Leishmania (Viannia) kDNA was detected in three wild ticks of the species R. microplus, collected from a collard peccary (P. tajacu) hunted in the forests of Madre de Dios. The HRM-PCR showed that one of the positive samples had a kDNA curve compatible with L. (V) guyanensis. Conclusion: The results showed the presence of L. (V) guyanensis DNA in R. microplus possibly acquired after biting a collarde peccary. Therefore, it is important to design future studies to clarify R. microplus involvement in the transmission of leishmaniasis.


Sujets)
Animaux , Mâle , Vecteurs arachnides/parasitologie , Artiodactyla/parasitologie , Infestations par les tiques/médecine vétérinaire , Leishmania guyanensis/isolement et purification , Rhipicephalus/parasitologie , Perissodactyla/parasitologie , Pérou/épidémiologie , Spécificité d'espèce , Infestations par les tiques/parasitologie , Réservoirs de maladies , Leishmaniose cutanéomuqueuse/transmission , Leishmaniose cutanéomuqueuse/épidémiologie , Réaction de polymérisation en chaîne , Leishmania guyanensis/génétique , ADN kinétoplastique/analyse , Maladies endémiques
3.
Medicina (B.Aires) ; 76(5): 304-306, Oct. 2016.
Article Dans Espagnol | LILACS | ID: biblio-841597

Résumé

El objetivo del presente trabajo es comunicar el hallazgo de Amblyomma triste por primera vez en la provincia de Santa Fe, Argentina, y sumar una nueva localidad para Amblyomma tigrinum en la misma provincia. Ambas especies de garrapatas son reconocidos vectores de Rickettsia parkeri, agente etiológico de la fiebre manchada. Los especímenes fueron colectados durante el mes de agosto de 2014 y diciembre de 2015 a partir de turistas en la Fundación Federico Wildermuth (31° 59'S, 61° 24'O), departamento de San Martín, provincia de Santa Fe. Se colectaron 5 garrapatas adultas que fueron identificadas morfológicamente como A. tigrinum (3 hembras y 1 macho) y A. triste (1 hembra). El presente hallazgo de A. triste y A. tigrinum representa el primero en incluir a ambas especies del complejo Amblyomma maculatum en una misma localidad y permite alertar sobre la presencia de vectores de R. parkeri en la zona. Nuevos estudios que incluyan el muestreo de un mayor número de garrapatas y la detección de R. parkeri permitirán dilucidar más aspectos sobre la situación de esta rickettsia en Santa Fe.


The aim of this communication is to report, for the first time, the occurrence of Amblyomma triste in Santa Fe province, Argentina, and to add a new isolation place for Amblyomma tigrinum. Both species of ticks are vectors of Rickettsia parkeri, a spotted fever group rickettsia. Ticks were recovered from tourists in August 2014 and December 2015 at the Federico Wildermuth Foundation (31° 59'S, 61° 24'O), San Martin Department, Santa Fe province. Five adult ticks were morphologically identified as A. tigrinum (3 females and 1 male) and A. triste (1 female). This is the first finding including both Amblyomma maculatum group species, A. triste and A. tigrinum, together in the same locality in Argentina. This finding suggests that this site might have favorable features for the development of both species of R. parkeri vector. Further studies including sampling of a larger number of ticks and detection of R. parkeri DNA are needed to better document the epidemiology of this rickettsia in Santa Fe.


Sujets)
Humains , Animaux , Mâle , Femelle , Vecteurs arachnides/microbiologie , Rickettsioses/transmission , Ixodidae/microbiologie , Argentine , Rickettsia/isolement et purification , Ixodidae/classification
4.
The Korean Journal of Parasitology ; : 87-91, 2016.
Article Dans Anglais | WPRIM | ID: wpr-36477

Résumé

Deer serve as reservoirs of tick-borne pathogens that impact on medical and veterinary health worldwide. In the Republic of Korea, the population of Korean water deer (KWD, Hydropotes inermis argyropus) has greatly increased from 1982 to 2011, in part, as a result of reforestation programs established following the Korean War when much of the land was barren of trees. Eighty seven Haemaphysalis flava, 228 Haemaphysalis longicornis, 8 Ixodes nipponensis, and 40 Ixodes persulcatus (21 larvae, 114 nymphs, and 228 adults) were collected from 27 out of 70 KWD. A total of 89/363 ticks (266 pools, 24.5% minimum infection rate) and 5 (1.4%) fed ticks were positive for Anaplasma phagocytophilum using nested PCR targeting the 16S rRNA and groEL genes, respectively. The 16S rRNA gene fragment sequences of 88/89 (98.9%) of positive samples for A. phagocytophilum corresponded to previously described gene sequences from KWD spleen tissues. The 16S rRNA gene fragment sequences of 20/363 (5.5%) of the ticks were positive for A. bovis and were identical to previously reported sequences. Using the ITS specific nested PCR, 11/363 (3.0%) of the ticks were positive for Bartonella spp. This is the first report of Anaplasma and Bartonella spp. detected in ticks collected from KWD, suggesting that ticks are vectors of Anaplasma and Bartonella spp. between reservoir hosts in natural surroundings.


Sujets)
Animaux , Anaplasma/génétique , Vecteurs arachnides/microbiologie , Bartonella/génétique , Chaperonine-60/génétique , Cervidae/parasitologie , Réservoirs de maladies/médecine vétérinaire , ARN ribosomique 16S/génétique , République de Corée/épidémiologie , Tiques/microbiologie
5.
Chinese Journal of Virology ; (6): 26-31, 2016.
Article Dans Chinois | WPRIM | ID: wpr-296221

Résumé

Until the recent emergence/re-emergence of human-pathogenic viruses in ticks, tick-borne viruses have been neglected as causative agents of human disease (particularly in China). To gain insight into the diversity of tick-borne viruses in Xinjiang Uygur Autonomous Region (northwestern China), we conducted illumina deep sequencing-based screening for virus-derived small RNAs in field-collected Ixodes persulcatus ticks. We found 32, 631 unique virus-matched reads. In particular, 77 reads mapped to the tick-borne group within the genus of Flavivirus, and covered 3.8%-2.4% viral genomes. In addition, 32 unique reads were specific to the Siberian subtype of tick-borne encephalitis viruses (TBEV-Sib) which have never been reported in Chinese TBE loci. We confirmed the potential existence of TBEV-Sib by amplification (using reverse transcription-polymerase chain reaction) of genomic fragments from the envelope gene or 3' genomic terminus from the pools of examined ticks. Both sequences demonstrated high homology to TBEV-Sib strains attached geographically to southern Siberia with nucleotide identity of 97.2%-95.5% and aminoacid identity of 99.4%-98.3%, respectively. In conclusion, we report, for the first time, detection of TBEV-Sib in the natural TBE loci of China. These novel data may provide genetic information for further isolation and epidemiologic investigation of TBEV-Sib.


Sujets)
Animaux , Humains , Vecteurs arachnides , Virologie , Chine , Virus de l'encéphalite à tiques (sous-groupe) , Classification , Génétique , Encéphalites à tiques , Virologie , Génome viral , Ixodes , Virologie , Données de séquences moléculaires , Phylogenèse
6.
Rev. chil. infectol ; 31(1): 54-65, feb. 2014. ilus, tab
Article Dans Espagnol | LILACS | ID: lil-706547

Résumé

Tick-borne rickettsioses are worldwide infectious diseases that are considered emerging and re-emerging. Until recently the only tick-borne rickettsiosis present in Latin America was Rickettsia rickettsii infection, but to date, with the incorporation of new tools as PCR and sequencing and the quick cellular close tube cultures (Shell-vial), new species has been involved as human pathogens. In these guidelines, we offer an update of the microbiological assays for diagnosing rickettsioses. Besides we have included a section in which the most important hard ticks involved in human rickettsioses in Latinoamerica are detailed.


Las rickettsiosis transmitidas por garrapatas son afecciones de distribución mundial, que por diferentes motivos se pueden considerar emergentes y reemergentes. Hasta hace escasos años la única rickettsiosis transmitida por garrapatas en Latinoamérica era la infección por Rickettsia rickettsii, pero en la actualidad y fundamentalmente, gracias a la incorporación de nuevas herramientas para el diagnóstico microbiológico como la reacción en cadena de la polimerasa y secuenciación o el cultivo celular rápido en tubo cerrado, se han descrito e involucrado otras especies de Rickettsia en la producción de patología humana. En estas guías se detallan y describen las diferentes técnicas utilizadas para el diagnóstico microbiológico de las rickettsiosis. Además, se incluye una sección en la que se detallan las especies más importantes de garrapatas duras relacionadas con las rickettsiosis en Latinoamérica, con claves para su clasificación taxonómica.


Sujets)
Animaux , Humains , Vecteurs arachnides/microbiologie , Rickettsioses/diagnostic , Rickettsia/classification , Maladies transmises par les tiques/diagnostic , Tiques/microbiologie , Techniques de culture cellulaire , Technique d'immunofluorescence indirecte , Amérique latine , Réaction de polymérisation en chaîne , Rickettsioses/microbiologie , Rickettsioses/transmission , Rickettsia/isolement et purification , Fièvre pourprée des Montagnes Rocheuses/diagnostic , Fièvre pourprée des Montagnes Rocheuses/microbiologie , Maladies transmises par les tiques/microbiologie , Tiques/anatomie et histologie , Tiques/classification
7.
The Korean Journal of Parasitology ; : 225-229, 2014.
Article Dans Anglais | WPRIM | ID: wpr-121881

Résumé

A total of 9,281 larval chigger mites were collected from small mammals captured at Hwaseong-gun, Gyeonggi-do (Province) (2,754 mites from 30 small mammals), Asan city, Chungcheongnam-do (3,358 mites from 48 mammals), and Jangseong-gun, Jeollanam-do (3,169 for 62 mammals) from April-November 2009 in the Republic of Korea (= Korea) and were identified to species. Leptotrombidium pallidum was the predominant species in Hwaseong (95.8%) and Asan (61.2%), while Leptotrombidium scutellare was the predominant species collected from Jangseong (80.1%). Overall, larval chigger mite indices decreased from April (27.3) to June (4.9), then increased in September (95.2) and to a high level in November (169.3). These data suggest that L. pallidum and L. scutellare are the primary vectors of scrub typhus throughout their range in Korea. While other species of larval chigger mites were also collected with some implications in the transmission of Orientia tsutsugamushi, they only accounted for 11.2% of all larval chigger mites collected from small mammals.


Sujets)
Animaux , Vecteurs arachnides , Larve/microbiologie , Orientia tsutsugamushi/isolement et purification , République de Corée , Rodentia , Fièvre fluviale du Japon/microbiologie , Trombiculidae/classification
8.
Biomédica (Bogotá) ; 33(supl.1): 31-37, set. 2013. mapas, tab
Article Dans Anglais | LILACS | ID: lil-695794

Résumé

Introduction: Since the middle of last century, cases of rickettsiosis have been found in Panamá when outbreaks of murine typhus and spotted fever were reported. Since then, little information exists about its prevalence in this country, since it is most often is misdiagnosed as another disease. Objectives: The aim of this paper is to demonstrate the presence of Rickettsia infections in humans in three locations in Panamá. These locations are agricultural areas, near forested areas or those who work in zoo. Materials and methods: Three locations where chosen for this study: Tortí, El Valle de Antón and workers in the Summit Municipal Park in Panamá City. All volunteers signed an informed consent and answered a questionnaire. The samples were analyzed for the detection of rickettsial spotted fever and typhus group by the indirect immunofluorescence (using commercial kits) and antigens of Rickettsia rickettsii and R. amblyommii. Results: Blood samples were taken from 97 volunteers in Tortí (25), El Valle de Anton (37) and Summit Municipal Park (35). Of these, a total of 38 (39%) samples reacted to one of the two methods: eight (32%) in Tortí, 18 (48%) in El valle and 12 (34%) in Summit Municipal Park. Conclusion: The results show a high prevalence of antibodies to Rickettsia belonging to the spotted fever group in each of the three study areas, in addition to presenting evidence of the typhus group Rickettsia in El Valle de Anton. These areas could be considered endemic for rickettsiosis as there are conditions for maintaining them.


Introducción. Desde mediados del siglo pasado, se conocen en Panamá casos de rickettsiosis, cuando fueron reportados brotes de tifus en ratones y de fiebres manchadas. A partir de entonces, poca información se tiene sobre su prevalencia en este país, lo cual se debe principalmente a que son confundidos con otras enfermedades. Objetivos. El objetivo de este trabajo fue demostrar la presencia de rickettsiosis en humanos provenientes de tres localidades de Panamá, que corresponden a zonas agropecuarias, cercanas a bosques, o que trabajaban en zoológicos. Materiales y métodos. Se escogieron tres localidades para este estudio: Tortí (provincia de Panamá), El Valle de Antón (provincia de Coclé) y el Parque Municipal Summit en Ciudad de Panamá. Los voluntarios firmaron un consentimiento informado, además de responder un cuestionario. De cada voluntario se extrajo sangre venosa, la que fue analizada por medio de inmunoflorescencia indirecta, utilizando kits comerciales y láminas sensibilizadas con antígenos cultivados de Rickettsia rickettsii y Rickettsia amblyommii . Resultados. Se tomaron muestras de 97 voluntarios, 25 en Tortí, 37 en El Valle de Antón y 35 en el Parque Municipal Summit. De estos, 38 (39 %) de las muestras fueron positivas en algunas de las dos técnicas practicadas: 8 (32 %) en Tortí, 18 (48 %) en El Valle y 12 (34 %) en el Parque Municipal Summit. Conclusión. Se demuestra una alta prevalencia de anticuerpos contra Rickettsia del grupo de las fiebres manchadas en las tres áreas de estudio, además de presentarse evidencia de títulos para Rickettsia del grupo tifus en El Valle de Antón. Estas zonas podrían considerarse como endémicas por rickettsiosis, ya que existen condiciones que permiten el mantenimiento de las mismas.


Sujets)
Animaux , Humains , Anticorps antibactériens/sang , Rickettsioses/épidémiologie , Rickettsia/immunologie , Maladies des agriculteurs/épidémiologie , Animaux de zoo/parasitologie , Antigènes bactériens/immunologie , Vecteurs arachnides/microbiologie , Réservoirs de maladies/parasitologie , Maladies endémiques , Exposition environnementale , Technique d'immunofluorescence indirecte , Forêts , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Ixodidae/microbiologie , Exposition professionnelle , Panama/épidémiologie , Animaux de compagnie/parasitologie , Population rurale , Rickettsioses/immunologie , Rickettsia ricketsii/immunologie , Études séroépidémiologiques , Spécificité d'espèce , Enquêtes et questionnaires , Morsures de tiques/microbiologie , Infestations par les tiques/épidémiologie , Infestations par les tiques/prévention et contrôle , Infestations par les tiques/médecine vétérinaire , Population urbaine
9.
Biomédica (Bogotá) ; 33(supl.1): 38-51, set. 2013. ilus, graf, tab
Article Dans Espagnol | LILACS | ID: lil-695795

Résumé

Introducción. Las rickettsias son bacterias patógenas usualmente transmitidas por ectoparásitos, como garrapatas, piojos o pulgas. En la última década se presentaron tres brotes de rickettsiosis con casos fatales en la región noroccidental de Antioquia y en un municipio limítrofe de Córdoba. Objetivo. Describir la ecología y la epidemiología de las infecciones por Rickettsia spp. en el Urabá antioqueño. Materiales y métodos. Se obtuvieron muestras de 354 roedores y se recolectaron 839 ectoparásitos de estos en los municipios de Apartadó, Turbo y Necoclí. Asimismo, se obtuvieron 220 sueros humanos. Estas muestras fueron estudiadas por reacción en cadena de la polimerasa (PCR) e inmunofluorescencia indirecta (IFI) para la detección de infección por rickettsias. Resultados. Por IFI se detectaron anticuerpos antirickettsias en 130 (43 %) de los roedores y en 53 (24 %) de los sueros humanos estudiados. Además, se amplificaron secuencias del gen gltA específicas del género Rickettsia en 23 (6,8 %) muestras de hígado de roedores, las cuales mostraron una similitud del 98,7 % con R. prowazekii . Una secuencia de gltA obtenida de larvas de garrapatas del género Amblyomma sp., tuvo una identidad mayor de 99 % con las secuencias de R. tamurae . Conclusión. Estos resultados demuestran la circulación de rickettsias en roedores, ectoparásitos y humanos en los municipios estudiados.


Introduction: Rickettsia spp. are tick, flea or lice-borne pathogenic bacterium, usually carried by rodents. In the last decade three outbreaks of rickettsial disease including fatalities, occurred in the provinces of Antioquia and Córdoba in northwestern Colombia. Objective: The purpose of this study was to perform an ecological and epidemiological description of the Rickettsia spp infection in the recently affected region of Colombia. Materials and methods: Samples were obtained from 354 rodents and their parasites captured in the municipalities of Apartadó, Turbo and Necoclí. Likewise, 220 human sera were also collected, for detection of infection by Rickettsia spp. Results: Indirect immunofluorescence assay (IFA) revealed that 130 (43%) of the rodents and 53 (24%) of the humans produced antibodies to Rickettsia spp. Additionally, rickettsial DNA was amplified by PCR from 23 (6.8%) rodent liver samples using primers directed to the genus specific gltA gene. While gltA sequences from rodent samples exhibited a 98.7% similitude with R . prowazekii, a sequence amplified from larvae of Amblyomma sp exhibited identities of >99% similarity with R. tamurae . Conclusion: These results demonstrate the presence of rickettsia in rodents, ectoparasites and humans throughout the municipalities studied.


Sujets)
Adulte , Animaux , Enfant , Femelle , Humains , Mâle , Adulte d'âge moyen , Anticorps antibactériens/sang , Vecteurs arachnides/microbiologie , Réservoirs de maladies/parasitologie , Rickettsioses/épidémiologie , Rickettsia/isolement et purification , Rodentia/parasitologie , Infestations par les tiques/médecine vétérinaire , Colombie/épidémiologie , Épidémies de maladies , Maladies endémiques , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Larve/microbiologie , Foie/microbiologie , Mites (acariens)/microbiologie , Phylogenèse , Rickettsioses/sang , Rickettsioses/transmission , Rickettsioses/médecine vétérinaire , Rickettsia/génétique , Rickettsia/immunologie , Rodentia/sang , Études séroépidémiologiques , Facteurs socioéconomiques , Infestations par les tiques/épidémiologie , Tiques/microbiologie
10.
Biomédica (Bogotá) ; 33(supl.1): 161-178, set. 2013. tab
Article Dans Espagnol | LILACS | ID: lil-695807

Résumé

Las rickettsiosis son entidades clínicas de tipo zoonótico, causadas por bacterias intracelulares estrictas de los géneros Rickettsia y Orientia, pertenecientes a la familia Rickettsiaceae. Su ecología está determinada por factores ambientales y la presencia de vectores específicos que condicionan el establecimiento y la epidemiología en diferentes regiones del mundo. En las Américas, durante el siglo XX, únicamente eran reconocidas tres de estas enfermedades: la fiebre manchada de las Montañas Rocosas, el tifus epidémico y el tifus endémico, Sin embargo, a partir del año 2000 se han descrito mas de 10 especies diferentes previamente desconocidas en este continente, tanto en artrópodos como en casos clínicos, hecho que permite clasificarlas como entidades clínicas emergentes y reemergentes. Dadas las manifestaciones clínicas de las enfermedades causadas por rickettsias, siendo la gran mayoría inespecíficas y, por lo mismo, compartidas con otras enfermedades infecciosas, especialmente virales y bacterianas, han sido enmarcadas entre los diagnósticos diferenciales del síndrome febril agudo, tanto en áreas urbanas como tropicales. En la actualidad, se cuenta con métodos diagnósticos directos e indirectos, que son útiles en la identificación del agente infeccioso, en este caso, causante de rickettsiosis.


Rickettsioses are a group of zoonotic diseases caused by strict intracellular bacteria of the genus Rickettsia and Orientia which belong to the Rickettsiaceae family. Their ecology is influenced by environmental factors and the presence of specific vectors that determine the establishment and epidemiology in different world regions. In America, during the 20 th century, only three of these diseases were recognized: Rocky Mountain spotted fever, epidemic typhus and endemic typhus. However, since 2000, more than 10 different species that had previously been unknown in this continent have been described, both in arthropods and in clinical cases, fact that classifies them as emerging and re-emerging diseases. Given the clinical manifestations of the diseases caused by rickettsias, being the majority unspecific and, therefore, shared with other infectious diseases, especially viral and bacterial, they have been framed within the differential diagnoses of acute febrile syndrome in urban and tropical areas. Nowadays, there are direct and indirect diagnostic methods, which are useful in the definition of the infectious agent, in this case, the cause of rickettsioses.


Sujets)
Animaux , Humains , Rickettsioses/épidémiologie , Maladies transmises par les tiques/épidémiologie , Amériques/épidémiologie , Vecteurs arachnides/microbiologie , Technique de Western , Maladies transmissibles émergentes , Réservoirs de maladies/parasitologie , Réaction de polymérisation en chaîne , Rickettsioses/classification , Rickettsioses/diagnostic , Rickettsioses/transmission , Rickettsia/classification , Rickettsia/isolement et purification , Spécificité d'espèce , Coloration et marquage , Fièvre fluviale du Japon/épidémiologie , Fièvre fluviale du Japon/transmission , Tests sérologiques/méthodes , Morsures de tiques/microbiologie , Infestations par les tiques/épidémiologie , Infestations par les tiques/médecine vétérinaire , Maladies transmises par les tiques/diagnostic , Tiques/microbiologie
11.
The Korean Journal of Parasitology ; : 327-331, 2012.
Article Dans Anglais | WPRIM | ID: wpr-45624

Résumé

Monthly surveys were conducted to investigate the occurrence of chigger mites and seroprevalence of scrub typhus among small mammals in Jeollanam-do, the southwestern part of Korea, from November 2006 through October 2007. Fifty-eight small mammals, including 57 Apodemus agrarius (98.3%) and 1 Crocidura lasiura (1.7%), were captured, and a total of 4,675 chigger mites representing 4 genera and 8 species were collected from them. The chigger infestation rate among small mammals was 69.0%. The most predominant species in A. agrarius was Leptotrombidium scutellare (54.0%), followed by Leptotrombidium pallidum (39.4%), Leptotrombidium orientale (4.4%), Leptotrombidium palpale (1.1%), Neotrombicula tamiyai (0.6%), Eushoengastia koreaensis (0.3%), Neotrombicula gardellai (0.3%), and Cheladonta ikaoensis (<0.1%). The chigger index of A. agrarius was the highest in October (740.0), followed by November (242.0), September (134.6), March (98.3), February (38.2), January (35.3), December (34.5), April (30.8), and May (1.7). The average antibody positive rate of scrub typhus in wild rodents was 50.0%. The seropositive rates were high in October (100.0%) and November (83.3%), whereas those in other months were relatively low (28.6-57.1%). The chigger index of L. scutellare rapidly increased in September to form an acuminate peak in October, followed by a gradual decline. These results suggest that the outbreak of scrub typhus in the southwestern part of Korean peninsula is mostly due to L. scutellare.


Sujets)
Animaux , Humains , Anticorps antibactériens/sang , Spécificité des anticorps , Vecteurs arachnides/microbiologie , Réservoirs de maladies , Murinae/parasitologie , Orientia tsutsugamushi/immunologie , Dynamique des populations , Surveillance de la santé publique , République de Corée/épidémiologie , Maladies des rongeurs/parasitologie , Fièvre fluviale du Japon/épidémiologie , Saisons , Études séroépidémiologiques , Musaraignes/parasitologie , Spécificité d'espèce , Trombidiose/parasitologie , Trombiculidae/microbiologie
12.
Asian Pacific Journal of Tropical Medicine ; (12): 459-464, 2012.
Article Dans Anglais | WPRIM | ID: wpr-819652

Résumé

OBJECTIVE@#To investigate the precise species of tick vector and the Borrelia spirochete pathogen at the Heilongjiang Province international border with Russia.@*METHODS@#In this study, ticks were collected from 12 Heilongjiang border crossings (including grasslands, shrublands, forests, and plantantions) to determine the rate and species type of spirochete-infected ticks and the most prevalent spirochete genotypes.@*RESULTS@#The ticks represented three genera and four species of the Ixodidae family [Ixodes persulcatus, Dermacentor silvarum, Haemaphysalis concinna and Haemaphysalis japonica]. Ixodes persulcatus had the highest amount of Borrelia burgdorferi sensu lato infection of 25.6% and the most common species of Borrelia isolated from Ixodes persulcatus was Borrelia garinii, strain PD91.@*CONCLUSIONS@#Our results suggest that Borrelia garinii PD91-infected Ixodes persulcatus may be the principal cause of Lyme disease in the border crossing areas of Heilongjiang Province.


Sujets)
Animaux , Vecteurs arachnides , Microbiologie , Groupe Borrelia burgdorferi , Génétique , Chine , Émigration et immigration , Ixodes , Microbiologie , Maladie de Lyme , Microbiologie , Réaction de polymérisation en chaîne , Polymorphisme de restriction , ARN , Génétique , Russie
13.
Chinese Journal of Virology ; (6): 252-257, 2012.
Article Dans Chinois | WPRIM | ID: wpr-354739

Résumé

To understand the maintenance and transmission of SFTS virus, the potential vector ticks were collected from sheep, cattle and dogs in the endemic areas of SFTSV in Shandong Province. Among the collected ticks, the dominant species was H. longicornis ticks. Real-time PCR for RNA detection, virus isolation and characterization, genomic sequencing, phylogenetic and antigenic analysis were performed in this investigation. The results showed that the SFTS viral RNA was detected in 2.14% H. longicornis, and a SFTS virus was isolated from one of viral RNA positive ticks collected from sheep. Whole genome analysis of the SFTSV isolates with 11 human-origin SFTS virus revealed a highly pairwise similarity, and the growth curve analysis showed nearly identical in virus yield and the dynamic of virus reproduction compared to human derived viral isolates. Immunofluorescence and neutralization test showed identical serological reaction character of the two different origin viral strains. In this study, the characters of a SFTSV isolate was firstly described, which suggested that the tick species H. longicornis acting important vector role in the transmission of SFTS virus.


Sujets)
Animaux , Bovins , Chiens , Humains , Animaux domestiques , Parasitologie , Vecteurs arachnides , Virologie , Infections à Bunyaviridae , Virologie , Lignée cellulaire , Bétail , Parasitologie , Données de séquences moléculaires , Phlebovirus , Classification , Génétique , Phylogenèse , Ovis , Tiques , Virologie
14.
The Korean Journal of Parasitology ; : 419-422, 2011.
Article Dans Anglais | WPRIM | ID: wpr-78162

Résumé

Severe tick infestation was found in a hare in a suburban area of Nanchang, Jiangxi Province, China. We sampled ticks and identified them based on their morphologic characteristics. Three species, Ixodes sinensis, which is commonly found in China and can experimentally transmit Borrelia burgdorferi, Rhipicephalus haemaphysaloides, and Haemaphysalis longicornis which can transmit Lyme disease were detected with an optical microscope and a stereomicroscope. Risk of spreading ticks from suburban to urban areas exists due to human transportation and travel between the infested and non-infested areas around Nanchang.


Sujets)
Animaux , Femelle , Humains , Mâle , Vecteurs arachnides/classification , Borrelia burgdorferi/physiologie , Chine , Issue fatale , Lepus/parasitologie , Ixodidae/classification , Maladie de Lyme/microbiologie , Risque , Infestations par les tiques/parasitologie
15.
The Korean Journal of Parasitology ; : 437-440, 2011.
Article Dans Anglais | WPRIM | ID: wpr-107277

Résumé

Babesia spp. were detected from 4 asymptomatic pukus captured on a game ranch in central Zambia in October 2008. Blood smears were examined in 4 species of aymptomatic free-ranging antelopes, namely the puku (Kobus vordanii), reedbuck (Redunca arundinum), bushbuck (Tragelaphus sylvaticus), and kudu (Tragelaphus strepsiceros), and showed the presence of Babesia parasites only in the puku. In the puku, the prevalence of babesiosis was estimated at 33.3% (n=12), while the overall prevalence in all examined animals was 8.5% (n=47). The parasites showed morphological characteristics of paired ring-like stages with the length varying between 1.61 microm and 3.02 microm (mean=2.12 microm, n=27; SD=0.76 microm). Both the infected and non-infected pukus showed good body condition scores (BCS), while the dominant tick species detected from all animals were Rhipicephalus appendiculatus, Rhipicephalus spp., and Boophilus spp. To our knowledge this is the first report of Babesia spp. infection in pukus in Zambia. These findings suggest that wildlife could play an important role in the epidemiology of babesiosis in Zambia.


Sujets)
Animaux , Animaux sauvages/parasitologie , Antilopes/parasitologie , Vecteurs arachnides/classification , Maladies asymptomatiques , Babesia/isolement et purification , Babésiose/épidémiologie , Érythrocytes/parasitologie , Prévalence , Rhipicephalus/classification , Infestations par les tiques/épidémiologie , Tiques/parasitologie , Zambie/épidémiologie
16.
An. bras. dermatol ; 85(6): 930-938, nov.-dez. 2010. ilus, tab
Article Dans Portugais | LILACS | ID: lil-573639

Résumé

As borrelioses constituem um grupo de doenças infecciosas causadas por espiroquetas do gênero Borrelia. A borreliose de Lyme, também denominada doença de Lyme, é uma doença infecciosa, não contagiosa, causada por espiroquetas pertencentes ao complexo Borrelia burgdorferi Sensu Lato e transmitida, mais frequentemente, por picada de carrapatos do gênero Ixodes. A doença apresenta quadro clínico variado, podendo desencadear manifestações cutâneas, articulares, neurológicas e cardíacas.


Borreliosis is an infectious disease caused by spirochetes of the genus Borrelia. Lyme borreliosis, also known as Lyme disease, is a non-contagious infectious disease caused by spirochetes belonging to the complex Borrelia burgdorferi sensu lato and more often transmitted by the bite of infected ticks of the genus Ixodes.The disease is characterized by a varied clinical profile, which can trigger cutaneous, articular, neurological and cardiac manifestations.


Sujets)
Animaux , Humains , Vecteurs arachnides , Borrelia burgdorferi , Ixodes , Maladie de Lyme , Maladie de Lyme/diagnostic , Maladie de Lyme/traitement médicamenteux , Maladie de Lyme/transmission
17.
Rev. panam. salud pública ; 27(6): 461-466, jun. 2010. tab
Article Dans Portugais | LILACS | ID: lil-555988

Résumé

Embora no Brasil o número de casos confirmados de febre maculosa esteja em declínio desde 2005, a taxa de mortalidade (20 a 30 por cento) ainda é muito alta quando comparada a outros países. Esse alto índice de mortalidade tem estreita relação com a dificuldade em fazer o diagnóstico e estabelecer a terapia apropriada. Apenas dois grupos de antibióticos têm comprovada eficácia clínica, o cloranfenicol e as tetraciclinas. Até pouco tempo atrás, as tetraciclinas eram reservadas aos pacientes adultos em virtude das alterações dentárias e ósseas em crianças. Recentemente, entretanto, a Academia Americana de Pediatria e diversos autores têm recomendado a utilização da doxiciclina também em crianças. Em casos mais severos, a falta de experiência com uma tetraciclina injetável no Brasil faz com que se opte pelo cloranfenicol injetável. Como o pronto diagnóstico e a escolha adequada do fármaco são fatores determinantes de um prognóstico positivo, todos os profissionais da saúde devem estar melhor preparados para reconhecer e tratar a febre maculosa.


Although the number of confirmed cases of spotted fever has been declining in Brazil since 2005, the mortality rate (20 percent to 30 percent) is still high in comparison to other countries. This high mortality rate is closely related to the difficulty in making the diagnosis and starting the correct treatment. Only two groups of antibiotics have proven clinical effectiveness against spotted fever: chloramphenicol and tetracyclines. Until recently, the use of tetracyclines was restricted to adults because of the associated bone and tooth changes in children. Recently, however, the American Academy of Pediatrics and various researchers have recommended the use of doxycycline in children. In more severe cases, chloramphenicol injections are often preferred in Brazil because of the lack of experience with injectable tetracycline. Since early diagnosis and the adequate drug treatment are key to a good prognosis, health care professionals must be better prepared to recognize and treat spotted fever.


Sujets)
Humains , Animaux , Mâle , Femelle , Grossesse , Enfant , Adulte , Fièvre pourprée des Montagnes Rocheuses/épidémiologie , Animaux sauvages/parasitologie , Antibactériens/administration et posologie , Antibactériens/effets indésirables , Antibactériens/usage thérapeutique , Vecteurs arachnides/microbiologie , Brésil/épidémiologie , Retard de diagnostic , Diagnostic différentiel , Notification des maladies , Réservoirs de maladies/parasitologie , Surveillance de la population , Complications infectieuses de la grossesse/traitement médicamenteux , Complications infectieuses de la grossesse/microbiologie , Rickettsia ricketsii/isolement et purification , Fièvre pourprée des Montagnes Rocheuses/diagnostic , Fièvre pourprée des Montagnes Rocheuses/traitement médicamenteux , Fièvre pourprée des Montagnes Rocheuses/physiopathologie , Fièvre pourprée des Montagnes Rocheuses/prévention et contrôle , Infestations par les tiques/médecine vétérinaire , Tiques/microbiologie
19.
The Korean Journal of Parasitology ; : 237-243, 2010.
Article Dans Anglais | WPRIM | ID: wpr-46696

Résumé

Comprehensive quarterly serosurveillance on scrub typhus in small mammals collected from military training sites located near the Demilitarized Zone (DMZ), northern Gyeonggi-do (Province), ROK was conducted to determine the potential rodent-borne and associated ectoparasite disease risks to military personnel. A total of 1,196 rodents and insectivores representing 8 species, Apodemus agrarius (87.3%, n = 1,044), Mus musculus (5.4%, n = 65), Crocidura lasiura (3.3%, n = 40), Microtus fortis (2.6%, n = 31), Micromys minutus (0.3%, n = 4), Tscherskia triton (0.3%, n = 4), Rattus norvegicus (0.3%, n = 4), and Myodes regulus (0.3%, n = 4) were assayed for the presence of antibodies to Orientia tsutsugamushi. O. tsutsugamushi antibodies were detected in 6 of 8 species and seroprevalence determined; A. agrarius (45.6%), M. musculus (23.1%), M. fortis (48.4%), M. minutus (50.0%), T. triton (50.0%), and R. norvegicus (25.0%). A total of 31,184 chigger mites collected from 508 rodents and insectivores were slide-mounted and 10 species belonging to 4 genera were identified. Leptotrombidium pallidum (53.4%) was the most frequently collected, followed by L. palpale (15.7%), Neotrombicula tamiyai (14.3%), L. orientale (10.7%), L. zetum (3.1%), Walchia fragilis (2.1%), and L. gemiticulum (0.8%), while the remaining 3 species, L. subintermedium, N. gardellai, and Euschoengastia koreaensis were rarely observed (prevalence < 10%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4), L. orientale (45.0), and L. palpale (21.4), were observed during the spring season.


Sujets)
Animaux , Humains , Anticorps antibactériens/immunologie , Vecteurs arachnides/classification , Réservoirs de maladies/classification , Installations militaires , Orientia tsutsugamushi/immunologie , République de Corée , Rodentia/classification , Fièvre fluviale du Japon/microbiologie , Études séroépidémiologiques , Trombiculidae/classification
20.
Journal of Veterinary Science ; : 197-203, 2010.
Article Dans Anglais | WPRIM | ID: wpr-115096

Résumé

The prevalence of tick-borne encephalitis virus (TBEV) in southern Korea was determined by collecting ticks using tick drags. A total of 4,077 of 6,788 ticks collected were pooled (649 pools) according to collection site, species, and developmental stage and assayed for TBEV. The TBEV protein E and NS5 gene fragments were detected using RT-nested PCR in six pools of nymphs collected from Jeju Island (2,491 ticks). The minimum field detection rates for TBEV were 0.17% and 0.14% for Haemaphysalis longicornis and Haemayphysalis. flava nymphs, respectively. The 252 bp NS5 and 477 bp protein E gene amplicons were sequenced. Phylogenetic analysis showed that the NS5 and protein E genes of the Jeju strain were clustered with Western subtype (98.0% and 99.4% identity, respectively). The Western subtype of TBEV is endemic in Korea, including Jeju Island. The study of vector and zoonotic host susceptibility to TBEV is required to better understand its potential impact on public health.


Sujets)
Animaux , Vecteurs arachnides/virologie , Séquence nucléotidique , Amorces ADN/génétique , Virus de l'encéphalite à tiques (sous-groupe)/classification , Encéphalites à tiques/épidémiologie , Données de séquences moléculaires , Phylogenèse , Prévalence , République de Corée/épidémiologie , RT-PCR , Analyse de séquence d'ADN , Tiques/virologie , Protéines de l'enveloppe virale/génétique
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