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1.
Diagn Microbiol Infect Dis ; 110(4): 116517, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39217856

RESUMO

The aim of this work was to develop a real-time PCR assay with a TaqMan® probe that detects a species-specific part of the 16S rDNA gene of Ehrlichia canis. Canine blood samples (n = 207), collected and tested by a conventional PCR assay within a study conducted by De Salvo et al., were simultaneously analyzed with the novel designed real-time PCR, and the results of both assays were compared. The agreement between the two methods was 97.6 % with a kappa value of 0.92186. Hereby, the standard error was 0.034416 and the 95 % confidence interval from 0.8544 to 0.98931. While the conventional PCR assay showed false negative results (2.42 %; 5/207), the real-time PCR assays showed a specificity of 100 %. The results of the current study showed that the developed assay presents sensitivity and specificity for the detection of E. canis in blood samples, adding a new tool for the diagnosis of this pathogen.

2.
Rev Argent Microbiol ; 56(3): 287-291, 2024.
Artigo em Espanhol | MEDLINE | ID: mdl-39095319

RESUMO

The first autochthonous case of rickettsiosis is reported here. The case occurred in the Costanera Sur Ecological Reserve, a protected area of the City of Buenos Aires, in August 2022, where 4 species of ticks were found, namely Amblyomma aureolatum, Ixodes auritulus sensu lato, Rhipicephalus sanguineus sensu stricto and Amblyomma triste. The epidemiological, ecological, clinical and laboratory aspects that allowed timely diagnosis and appropriate treatment are also described.


Assuntos
Amblyomma , Argentina , Animais , Humanos , Masculino , Amblyomma/microbiologia , Feminino , Rhipicephalus sanguineus/microbiologia , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rickettsiose do Grupo da Febre Maculosa/diagnóstico , Ixodes/microbiologia , Ixodidae/microbiologia
3.
Front Vet Sci ; 11: 1399783, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828369

RESUMO

Tick-borne infectious agents (TBIAs) include several bacteria and protozoa that can infect vertebrates, including humans. Some of these agents can cause important diseases from both a public health perspective, such as Lyme disease, and from an animal health and production viewpoint, such as Texas fever. In Chile, several studies have assessed the presence of tick-borne disease agents in vectors and mammal hosts, mainly in the northern regions, but few studies have assessed the presence of these agents in Central and Southern Chile. This study aimed to assess the presence of three groups of TBIAs-Borrelia, Anaplasmataceae, and Piroplasmida-in cricetid rodents of Central and Southern Chile. A total of 207 specimens from 13 localities between the O'Higgins and Los Lagos regions were captured. DNA was extracted from the liver and spleen, and subsequently underwent polymerase chain reaction (PCR) amplification targeting the 16S rRNA, flaB, and 18S rRNA genes to detect DNA from Borrelia, Anaplasmataceae, and Piroplasmida, respectively. Although no DNA from these TBIAs was detected, the DNA extraction process was validated by optimal DNA purity ratios (an A260/A280 ratio within the 1.6-2.0 range) and successful internal control amplification in all samples. These results, in addition to findings from previous reports, suggest a very low prevalence of these TBIAs in the rodent population studied. Further research into the factors influencing the presence of these agents and their vectors will provide insight into the reasons underlying this low prevalence.

4.
Parasit Vectors ; 17(1): 268, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918818

RESUMO

BACKGROUND: Ticks are obligate hematophagous ectoparasites involved in transmitting viruses of public health importance. The objective of this work was to identify the Jingmen tick virus in hard ticks from the Colombian Caribbean, an arbovirus of importance for public health. METHODS: Ticks were collected in rural areas of Córdoba and Cesar, Colombia. Taxonomic identification of ticks was carried out, and pools of 13 individuals were formed. RNA extraction was performed. Library preparation was performed with the MGIEasy kit, and next-generation sequencing (NGS) with MGI equipment. Bioinformatic analyses and taxonomic assignments were performed using the Galaxy platform, and phylogenetic analyses were done using IQ-TREE2. RESULTS: A total of 766 ticks were collected, of which 87.33% (669/766) were Rhipicephalus microplus, 5.4% (42/766) Dermacentor nitens, 4.2% (32/766) Rhipicephalus linnaei, and 3.0% (23/766) Amblyomma dissimile. Complete and partial segments 1, 2, 3, and 4 of Jingmen tick virus (JMTV) were detected in the metatranscriptome of the species R. microplus, D. nitens, and A. dissimile. The JMTVs detected are phylogenetically related to JMTVs detected in Aedes albopictus in France, JMTVs detected in R. microplus in Trinidad and Tobago, JMTVs in R. microplus and A. variegatum in the French Antilles, and JMTVs detected in R. microplus in Colombia. Interestingly, our sequences clustered closely with JMTV detected in humans from Kosovo. CONCLUSIONS: JMTV was detected in R. microplus, D. nitens, and A. dissimile. JMTV could pose a risk to humans. Therefore, it is vital to establish epidemiological surveillance measures to better understand the possible role of JMTV in tropical diseases.


Assuntos
Arbovírus , Ixodidae , Filogenia , Animais , Colômbia/epidemiologia , Ixodidae/virologia , Ixodidae/classificação , Arbovírus/genética , Arbovírus/isolamento & purificação , Arbovírus/classificação , Região do Caribe , Feminino , Masculino , Saúde Pública , Sequenciamento de Nucleotídeos em Larga Escala , Rhipicephalus/virologia , Rhipicephalus/classificação , Humanos , Amblyomma/virologia , Dermacentor/virologia
5.
J Am Vet Med Assoc ; 262(5): 698-704, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38417252

RESUMO

Rocky Mountain spotted fever (RMSF) is an international and quintessential One Health problem. This paper synthesizes recent knowledge in One Health, binational RMSF concerns, and veterinary and human medical perspectives to this fatal, reemerging problem. RMSF, a life-threatening tick-borne disease caused by the bacterium Rickettsia rickettsii, emerged during the first decade of the 21st century in impoverished communities in the southwestern US and northern Mexico. Lack of an index of suspicion, delay in diagnosis, and delayed initiation of antibiotic treatment contribute to fatality. Campaigns targeting dog neutering, restraint to residents' properties, and on-dog and on-premises treatment with acaricides temporarily reduce prevalence but are often untenable economically. Contemporary Mexican RMSF is hyperendemic in small communities and cities, whereas epidemics occur in the western US primarily in small tribal communities. In in both locations, the epidemics are fueled by free-roaming dogs and massive brown dog tick populations. In the US, RMSF has a case fatality rate of 5% to 7%; among thousands of annual cases in Mexico, case fatality often exceeds 30%.1,2 Numerous case patients in US border states have recent travel histories to northern Mexico. Veterinarians and physicians should alert the public to RMSF risk, methods of prevention, and the importance of urgent treatment with doxycycline if symptomatic. One Health professionals contribute ideas to manage ticks and rickettsial disease and provide broad education for the public and medical professionals. Novel management approaches include vaccine development and deployment, acaricide resistance monitoring, and modeling to guide targeted dog population management and other interventions.

6.
Zoonoses Public Health ; 71(2): 217-224, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38050875

RESUMO

BACKGROUND: On the American continent, Rhipicephalus sanguineus s.l. comprises two species: Rhipicephalus linnaei and R. sanguineus s.s. Each species has been identified as a potential vector of at least one of five species of pathogenic bacteria of the genus Rickettsia. In particular, Rickettsia massiliae is one of three species with the greatest importance in public health at the continental level. In Mexico, this species is reported exclusively in the Nearctic states of Baja California and Chihuahua. AIM: For this reason, the aim of this work was to provide new records of R. massiliae for the centre of the country derived from active acarological surveillance. MATERIALS AND METHODS: During the period of February-October 2019, 29 dogs from six municipalities in the state of Morelos were sampled. Hosts were visually inspected, and ticks were recovered and identified morphologically and molecularly by amplification of the 16S rDNA gene. Subsequently, five genes from members of the genus Rickettsia were amplified and sequenced. RESULTS: A total of 229 (117♀, 98♂ and 14 N) ticks identified as R. linnaei were recovered, two of which were positive for R. massiliae strains related to those recovered from Argentina and the United States. CONCLUSIONS: This work provides the second record of R. massiliae infecting R. linnaei in Mexico and the Americas, increasing the geographic distribution of this Rickettsia species in the Neotropical region, and providing information on the possible role of R. linnaei as a potential vector of this microorganism.


Assuntos
Doenças do Cão , Rhipicephalus sanguineus , Rhipicephalus , Rickettsia , Infestações por Carrapato , Cães , Animais , México/epidemiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Rickettsia/genética , Rhipicephalus sanguineus/microbiologia
7.
J Med Entomol ; 60(5): 1081-1087, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37410021

RESUMO

Tick-borne diseases have increased significantly in Europe and Spain in recent years. One strategy explored for tick surveillance and control is the study of the microbiota. The focus is on understanding the relationships between pathogens and endosymbionts within the microbiota and how these relationships can alter these arthropods' vectorial capacity. Thus, it is pivotal to depict the bacterial communities composing the microbiota of ticks present in specific territories. This work aimed to describe the microbiota present in 29 adult individuals of 5 tick species collected from 4 provinces of Castilla y Leon in northwestern Spain from 2015 to 2022. DNA extraction and sequencing of the V4 hypervariable region of 16S-rRNA was performed on the tick samples, with subsequent analysis of diversity, taxonomic composition, and correlations between genera of microorganisms. There were no differences in the alpha diversity of microbiota by tick species, nor were compositional changes evident at the phylum level for microorganisms. However, interindividual differences at the microbial genus level allowed spatial differentiation of the 5 tick species included in the study. Correlation analyses showed complex interactions between different genera of microbiota members. These findings provide an initial insight into the composition of the gut microbiota of various tick species in northwestern Spain, which can contribute to establishing surveillance and control measures to reduce diseases such as rickettsiosis, Lyme disease, and Crimean-Congo hemorrhagic fever.


Assuntos
Microbioma Gastrointestinal , Ixodidae , Doenças Transmitidas por Carrapatos , Carrapatos , Humanos , Animais , Carrapatos/microbiologia , Ixodidae/microbiologia , Espanha , Doenças Transmitidas por Carrapatos/epidemiologia , RNA Ribossômico 16S/genética
8.
Bol Med Hosp Infant Mex ; 80(Supl 1): 12-22, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37490688

RESUMO

BACKGROUND: Ehrlichia chaffeensis is responsible for most cases of human ehrlichiosis, an acute febrile tick-borne disease. This clinical entity is more commonly reported in adults from the United States. Therefore, it is of special interest to characterize this disease in children, given that very few cases in children have been reported outside of this country. CASE REPORT: We describe the case of a 15-year-old female from northeastern Mexico with a five-day history of myalgias, arthralgias, fever, abdominal pain, rash, and somnolence. The possibility of tick-borne disease was suspected considering that she lived with three tick-infested dogs that had recently died and a neighbor with similar symptoms who deteriorated rapidly and died a week earlier. Ehrlichia spp. was detected in blood samples by polymerase chain reaction. The patient completed a seven-day course of doxycycline and was discharged with complete resolution of symptoms. CONCLUSIONS: This case is the first report of ehrlichiosis in a pediatric patient in Mexico, illustrating the importance of considering tick-borne diseases as a differential diagnosis in patients with rash, fever, and altered level of consciousness. This initial clinical presentation may be indistinct from other conditions such as dengue, meningococcemia, and multisystem inflammatory syndrome in children (MIS-C), among others.


INTRODUCCIÓN: Ehrlichia chaffeensis es responsable de la mayoría de los casos de ehrlichiosis humana, una enfermedad febril aguda transmitida por garrapatas. Esta entidad clínica se reporta con mayor frecuencia en adultos de Estados Unidos. Por lo tanto, es de especial interés caracterizarla en niños, dado que se han reportado muy pocos casos en niños fuera de este país. CASO CLÍNICO: Se describe el caso de una paciente de sexo femenino de 15 años, originaria y residente del noreste de México con una historia de cinco días de mialgias, artralgias, fiebre, dolor abdominal, erupción cutánea y somnolencia. Se sospechó la posibilidad de una enfermedad transmitida por garrapatas considerando que convivió con tres perros infestados de garrapatas que habían muerto recientemente y una vecina con síntomas similares, quien se deterioró rápidamente y murió una semana antes. Ehrlichia spp. se detectó en una muestra sérica mediante reacción en cadena de la polimerasa. La paciente completó un curso de siete días de doxiciclina y fue dada de alta con resolución de los síntomas. CONCLUSIONES: Este caso es el primer reporte de ehrlichiosis en un paciente pediátrico en México que ilustra la importancia de considerar enfermedades transmitidas por garrapatas dentro del diagnóstico diferencial de pacientes con exantema, fiebre y alteración del estado de conciencia. Esta presentación clínica inicial puede ser indistinguible de otras entidades como dengue, meningococcemia y síndrome multisistémico inflamatorio, entre otras.


Assuntos
Ehrlichia chaffeensis , Ehrlichiose , Doenças Transmitidas por Carrapatos , Adulto , Feminino , Humanos , Criança , Animais , Cães , Adolescente , México , Ehrlichiose/diagnóstico , Ehrlichiose/tratamento farmacológico , Doxiciclina/uso terapêutico , Febre
9.
Pathogens ; 12(6)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37375474

RESUMO

Ticks and tick-borne diseases affect livestock productivity and cause significant economic losses. Therefore, surveillance of these pathogens and vectors is paramount to reducing these effects in livestock. This study aimed to identify Anaplasma marginale and Borrelia burgdorferi sensu lato in ticks collected from cattle. Molecular biology techniques were utilized to identify A. marginale for both types of samples, i.e., ticks and bovine blood. Serology of cattle using indirect immunofluorescence assay (IFA) was conducted to determine antibodies to B. burgdorferi s.l. from seven locations in Nuevo Leon, Mexico, between 2015 and 2017. From 404 bovines, 2880 ticks were collected: Rhipicephalus microplus (2391 females and 395 males), Amblyomma spp. (51 females and 42 males) and Dermacentor variabilis (1 female). Rhipicephalus microplus represented the largest specimens captured, with 96.7% within the seven study sites. PCR processed only 15% (442) of tick samples to identify A. marginale. Field genera proportions were followed to select testing tick numbers. Results showed that 9.9% (44/442) of A. maginale infected the pooled tick species, whereas the highest percent corresponded to 9.4% (38/404) in R. microplus. Regarding the molecular analysis of blood samples, 214 of 337 (63.5%) were positive for A. maginale. In each of the seven locations, at least one bovine sample tested positive for A. maginale. Borrelia burgdorferi s.l. was not found either in the ticks or serum samples. Two A.marginale DNA nucleotide sequences obtained in this study were deposited in the GenBank with the following accession numbers OR050501 cattle, and OR050500 R.microplus tick. Results of this work point to current distribution of bovine anaplasmosis in northern Mexico.

10.
Animals (Basel) ; 13(8)2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37106851

RESUMO

Brazilian spotted fever (BSF) is the most important tick-borne diseases affecting humans in Brazil. Cases of BSF have recently been reported in the Goiás state, midwestern Brazil. All cases have been confirmed by reference laboratories by seroconversion to Rickettsia rickettsii antigens. Because serological cross-reactions among different rickettsial species that belong to the spotted fever group (SFG) are common, the agent responsible for BSF cases in Goiás remains unknown. From March 2020 to April 2022, ticks and plasma were collected from dogs, horses and capybaras (Hydrochoerus hydrochaeris), and from the vegetation in an area where BSF cases have been reported and two areas under epidemiological surveillance in Goiás. Horses were infested by Amblyomma sculptum, Dermacentor nitens and Rhipicephalus microplus; dogs by Rhipicephalus sanguineus sensu lato (s.l.), Amblyomma ovale and A. sculptum, and capybaras by A. sculptum and Amblyomma dubitatum. Adults of A. sculptum, A. dubitatum, Amblyomma rotundatum and immature stages of A. sculptum and A. dubitatum, and Amblyomma spp. were collected from the vegetation. DNA of Rickettsia that did not belong to the SFG was detected in A. dubitatum, which was identified by DNA sequencing as Rickettsia bellii. Seroreactivity to SFG and Rickettsia bellii antigens was detected in 25.4% (42/165) of dogs, 22.7% (10/44) of horses and 41.2% (7/17) of capybaras, with higher titers for R. bellii in dogs and capybaras. The seropositivity of animals to SFG Rickettsia spp. antigens demonstrates the circulation of SFG rickettsiae in the region. Further research is needed to fully determine the agent responsible for rickettsiosis cases in this area.

11.
Rev. argent. microbiol ; Rev. argent. microbiol;55(1): 111-120, mar. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1441191

RESUMO

Resumen Se informa un caso autóctono de rickettsiosis por Rickettsia parkeri, ocurrido en junio del 2018 en la zona selvática del Parque Provincial Urugua-í, Misiones, Argentina, región sin registros previos de esta enfermedad en humanos. Se describen los aspectos epidemiológicos, ecológicos, clínicos y de laboratorio necesarios para el diagnóstico oportuno y el tratamiento adecuado. Se resalta el hecho de considerar a las rickettsiosis como diagnóstico diferencial ante un paciente con síndrome febril agudo exantemático; el antecedente epidemiológico de exposición al vector característico de la región, garrapatas del género Amblyomma, es un elemento fundamental.


Abstract We report an autochthonous case of Rickettsia parkeri rickettsiosis occurred in June 2018 in a forested area of the Urugua-í Provincial Park, Misiones, Argentina. No previous records of this disease in humans have been previously reported in this region. The epidemiological, ecological, clinical, and laboratory features required for a proper diagnosis and adequate treatment are described here. The fact of considering rickettsiosis as a differential diagnosis in a patient with exanthematic acute febrile syndrome is highlighted, being the epidemiological history of exposure to the vector (ticks of the genus Amblyomma) an essential element.

12.
Rev Argent Microbiol ; 55(1): 83-87, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-36163115

RESUMO

We report an autochthonous case of Rickettsia parkeri rickettsiosis occurred in June 2018 in a forested area of the Urugua-í Provincial Park, Misiones, Argentina. No previous records of this disease in humans have been previously reported in this region. The epidemiological, ecological, clinical, and laboratory features required for a proper diagnosis and adequate treatment are described here. The fact of considering rickettsiosis as a differential diagnosis in a patient with exanthematic acute febrile syndrome is highlighted, being the epidemiological history of exposure to the vector (ticks of the genus Amblyomma) an essential element.


Assuntos
Infecções por Rickettsia , Rickettsia , Humanos , Argentina/epidemiologia , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/tratamento farmacológico , Florestas
13.
Bol. méd. Hosp. Infant. Méx ; 80(supl.1): 12-22, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1513760

RESUMO

Abstract Background: Ehrlichia chaffeensis is responsible for most cases of human ehrlichiosis, an acute febrile tick-borne disease. This clinical entity is more commonly reported in adults from the United States. Therefore, it is of special interest to characterize this disease in children, given that very few cases in children have been reported outside of this country. Case report: We describe the case of a 15-year-old female from northeastern Mexico with a five-day history of myalgias, arthralgias, fever, abdominal pain, rash, and somnolence. The possibility of tick-borne disease was suspected considering that she lived with three tick-infested dogs that had recently died and a neighbor with similar symptoms who deteriorated rapidly and died a week earlier. Ehrlichia spp. was detected in blood samples by polymerase chain reaction. The patient completed a seven-day course of doxycycline and was discharged with complete resolution of symptoms. Conclusions: This case is the first report of ehrlichiosis in a pediatric patient in Mexico, illustrating the importance of considering tick-borne diseases as a differential diagnosis in patients with rash, fever, and altered level of consciousness. This initial clinical presentation may be indistinct from other conditions such as dengue, meningococcemia, and multisystem inflammatory syndrome in children (MIS-C), among others.


Resumen Introducción: Ehrlichia chaffeensis es responsable de la mayoría de los casos de ehrlichiosis humana, una enfermedad febril aguda transmitida por garrapatas. Esta entidad clínica se reporta con mayor frecuencia en adultos de Estados Unidos. Por lo tanto, es de especial interés caracterizarla en niños, dado que se han reportado muy pocos casos en niños fuera de este país. Caso clínico: Se describe el caso de una paciente de sexo femenino de 15 años, originaria y residente del noreste de México con una historia de cinco días de mialgias, artralgias, fiebre, dolor abdominal, erupción cutánea y somnolencia. Se sospechó la posibilidad de una enfermedad transmitida por garrapatas considerando que convivió con tres perros infestados de garrapatas que habían muerto recientemente y una vecina con síntomas similares, quien se deterioró rápidamente y murió una semana antes. Ehrlichia spp. se detectó en una muestra sérica mediante reacción en cadena de la polimerasa. La paciente completó un curso de siete días de doxiciclina y fue dada de alta con resolución de los síntomas. Conclusiones: Este caso es el primer reporte de ehrlichiosis en un paciente pediátrico en México que ilustra la importancia de considerar enfermedades transmitidas por garrapatas dentro del diagnóstico diferencial de pacientes con exantema, fiebre y alteración del estado de conciencia. Esta presentación clínica inicial puede ser indistinguible de otras entidades como dengue, meningococcemia y síndrome multisistémico inflamatorio, entre otras.

14.
Ticks Tick Borne Dis ; 13(6): 102021, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36116202

RESUMO

Cytauxzoonosis is an acute and highly lethal tick-borne disease of wild and domestic cats, and is widely distributed in Africa, Asia, Europe, the USA and Brazil. So far, only two tick species present on the USA are experimentally confirmed in Cytauxzoon transmission however, in Brazil and other continents, the epidemiology of the disease remains unknown. Evidences points to Panthera onca as a possible reservoir, but there is no evidence to point the vector. Therefore, this study evaluates the presence of Cytauxzoon spp. in wild felids from areas with and without records of Amblyomma sculptum this ixodid for comparison. Overall, 53 blood samples of P. onca, Puma concolor, and Leopardus pardalis from the Midwest region (MR; region with A. sculptum) and 143 blood and/or spleen samples from Leopardus geoffroyi, Leopardus wiedii, Leopardus munoai, Leopardus guttulus, Herpailurus yagouaroundi, L. pardalis, and P. concolor from Rio Grande do Sul State (RS; without A. sculptum). Only one feline sample was negative for Cytauxzoon sp. from MR; no samples from RS were positive. In total, 507 ticks were identified from MR felids, with predominance of A. sculptum (69.23%). In RS, there were 93 ixodids, of which 90.32% were Amblyomma aureolatum. The difference in the tick fauna of the two regions studied (presence/absence of A. sculptum) reflects the results found. This study highlighted A. sculptum as a possible vector since this hemoparasite was abundantly observed in areas where it occurs, also, there was no evidence of Cytauxzoon spp. where it was absent. Additionally, the study supported the suggestion that P. onca is the reservoir for the agent in MR.

15.
Artigo em Inglês | MEDLINE | ID: mdl-35627785

RESUMO

Of the documented tick-borne diseases infecting humans in México, Rocky Mountain spotted fever (RMSF), caused by the Gram-negative bacterium Rickettsia rickettsii, is responsible for most fatalities. Given recent evidence of brown dog tick, Rhipicephalus sanguineus s.l., as an emerging vector of human RMSF, we aimed to evaluate dogs and their ticks for rickettsiae infections as an initial step in assessing the establishment of this pathosystem in a poorly studied region of northeastern México while evaluating the use of dogs as sentinels for transmission/human disease risk. We sampled owned dogs living in six disadvantaged neighborhoods of Reynosa, northeastern México to collect whole blood and ticks. Of 168 dogs assessed, tick infestation prevalence was 53%, composed of exclusively Rh. sanguineus s. l. (n = 2170 ticks). Using PCR and sequencing, we identified an overall rickettsiae infection prevalence of 4.1% (n = 12/292) in ticks, in which eight dogs harbored at least one infected tick. Rickettsiae infections included Rickettsia amblyommatis and Rickettsia parkeri, both of which are emerging human pathogens, as well as Candidatus Rickettsia andeanae. This is the first documentation of pathogenic Rickettsia species in Rh. sanguineus s.l. collected from dogs from northeastern México. Domestic dog infestation with Rickettsia-infected ticks indicates ongoing transmission; thus, humans are at risk for exposure, and this underscores the importance of public and veterinary health surveillance for these pathogens.


Assuntos
Doenças do Cão , Rhipicephalus sanguineus , Rickettsia , Infestações por Carrapato , Animais , Doenças do Cão/epidemiologia , Cães , Humanos , México/epidemiologia , Rhipicephalus sanguineus/microbiologia , Rickettsia/genética , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária
16.
Insects ; 13(3)2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35323561

RESUMO

Rocky Mountain spotted fever (RMSF) is a significant health problem in Sonora, Mexico. The tick vector, Rhipicephalus sanguineus, feeds almost exclusively on domestic dogs that, in this region, also serve as the reservoir for the tick-borne pathogen, Rickettsia rickettsii. A process-based mathematical model of the life cycle of R. sanguineus was developed to predict combinations of insecticidal dog collars and long-lasting insecticidal wall treatments resulting in suppression of indoor tick populations. Because of a high burden of RMSF in a rural community near the Sonora state capital of Hermosillo, a test area was treated with a combination of insecticidal dog collars and long-lasting insecticidal wall treatments from March 2018 to April 2019, with subsequent reduction in RMSF cases and deaths. An estimated 80% of the dogs in the area had collars applied and 15% of the houses were treated. Data on tick abundance on walls and dogs, collected during this intervention, were used to parameterize the model. Model results show a variety of treatment combinations likely to be as successful as the one carried out in the test community.

17.
Rev. bras. parasitol. vet ; 31(2): e021621, mar. 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1381609

RESUMO

Canine monocytic ehrlichiosis (CME) is one of the most important tick-borne diseases worldwide, with multisystemic presentations. Immune dysregulation has been proposed as the primary mechanism involved in its pathogenesis and in tissue injury in dogs with CME. Experimental infection of German Shepherd dogs in the present study demonstrated that CME caused marked pathological changes in their lymph nodes and spleen, and also gave rise to mononuclear infiltration in organs and tissues. Immunophenotyping of cells in lymph nodes, spleen and injured tissues highlighted differences in lymphocyte subsets, local expression of immunoglobulin subclasses and MHCII molecules between infected and control dogs. These findings suggest that the immunophenotypic and immunopathological changes in dogs with acute experimental CME are related to Th1 bias and compartmentalized immune response.(AU)


A erliquiose monocítica canina (EMC) é uma das doenças veiculadas por carrapatos com apresentações multisistêmicas mais relevantes em todo o mundo. A desregulação do sistema imune vem sendo proposta como o principal mecanismo envolvido na patogênese e lesão de tecidos em cães com EMC. A infecção experimental de pastores alemães nesta pesquisa evidenciou marcadas alterações patológicas em linfonodos, baço e também infiltração mononuclear em órgãos e tecidos. A imunofenotipagem de células em linfonodos, baço e tecidos lesados destacou diferenças em subconjuntos de linfócitos, expressão local de subclasses de imunoglobulinas e de moléculas MHCII entre cães infectados e controle. Esses achados sugerem que um viés Th1 e uma resposta imune compartimentalizada estão relacionados às alterações imunofenotípicas e imunopatológicas em cães com EMC experimental aguda.(AU)


Assuntos
Animais , Imunofenotipagem/veterinária , Ehrlichiose/fisiopatologia , Ehrlichia canis/patogenicidade , Cães/parasitologia
18.
Rev. Bras. Parasitol. Vet. (Online) ; 31(3): e006622, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1381866

RESUMO

A dog that shared habitat with domestic animals in a cattle farm and that was exposed to wildlife was taken to a private practitioner for clinical examination. The analyses conducted on the patient revealed the presence of Babesia bigemina by a molecular test. Clinical signs such as lethargy, anorexia and hyperthermia > 39 °C, pale mucous membranes and blood urine were observed in the patient. The animal was treated with imidocarb dipropionate (two doses each 0.5 ml/10 kg b.w. at an interval of 14 days). On treatment day 7, the clinical signs were mostly reduced. On day 30, PCR was carried out to assess the efficacy of the treatment, with a negative result. This case represents the first report of babesiosis due to B. bigemina in a dog living on a cattle farm in Mexico. It indicates the lower host specify of these pathogens and that dogs can play a role as sentinels of vector-borne parasites in livestock animals.(AU)


Um cão que compartilhava hábitat com animais domésticos em uma fazenda de gado e que foi exposto à vida selvagem foi levado a um clínico particular para que fosse examinado. As análises realizadas no paciente revelaram a presença de Babesia bigemina por um teste molecular. Sinais clínicos, como letargia, anorexia e hipertermia > 39°C, mucosas pálidas e sangue na urina foram observados no paciente. O animal foi tratado com dipropionato de imidocarb (duas doses cada 0,5 ml/10 kg de peso corporal em um intervalo de 14 dias). No dia de tratamento 7, os sinais clínicos foram reduzidos. No dia 30, foi realizada PCR para avaliar a eficácia do tratamento, com resultado negativo. Esse caso representa o primeiro relato de babesiose por B. bigemina em um cão que vive em uma fazenda de gado no México. Isso indica que o hospedeiro inferior especifica esses patógenos, e que os cães podem desempenhar um papel como sentinelas de parasitas transmitidos por vetores em animais de criação.(AU)


Assuntos
Animais , Babesia/efeitos dos fármacos , Babesiose/diagnóstico , Cães/parasitologia , Antiprotozoários/administração & dosagem , Filogenia , Zona Rural , Reação em Cadeia da Polimerase/veterinária , Técnicas de Diagnóstico Molecular/veterinária , Imidocarbo/análogos & derivados , México
19.
Ticks Tick Borne Dis ; 12(5): 101765, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34146934

RESUMO

Rangelia vitalii is a protozoan parasite that causes a hemorrhagic and hemolytic disease in dogs known as rangeliosis. Current reports of the disease are concentrated in the southern and southeastern regions of Brazil, as well as in Uruguay, Argentina, and Paraguay, and mainly concern domestic dogs. South American wild canids, such as the crab-eating fox (Cerdocyon thous), the pampas fox (Lycalopex gymnocercus), and the maned wolf (Chrysocyon brachyurus) may also be affected, although existing reports are restricted to Brazil. The present study aimed to detect R. vitalii parasitism in the Uruguayan wild fox population. DNA extracted from the blood and/or spleen samples of road-killed C. thous and L. gymnocercus found in northern Uruguay were subjected to polymerase chain reaction (PCR) to amplify a 551-bp fragment of the Rangelia 18S rRNA gene. A total of 62 wild canids, including 38 C. thous and 24L. gymnocercus, were analyzed. Five crab-eating fox samples (13.2%) were positive for R. vitalii, with 99.5-100% identity between the sequences. All samples from pampas fox tested negative for R. vitalii. When compared with the R. vitalii sequences available in GenBank, a similarity of 98.9-100% was revealed. Molecular analysis results suggest that R. vitalii is circulating in the crab-eating fox population in Uruguay; however, its veterinary relevance for these foxes remains unknown.


Assuntos
Canidae , Piroplasmida/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Animais , Feminino , Masculino , Prevalência , Infecções Protozoárias em Animais/parasitologia , Uruguai/epidemiologia
20.
Front Public Health ; 9: 577789, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777873

RESUMO

Spotted Fever Rickettsioses (SFR) are diseases caused by bacteria of the genus Rickettsia, and are transmitted mainly by ticks. Its eco-epidemiological scenarios vary spatially, and may also vary over time due to environmental changes. It is the main disease transmitted by ticks to humans in Brazil, with the state of Paraná (PR) having the sixth highest number of notified incidences in the country. However, information is lacking regarding the SFR disease cycles at likely infection sites within PR. During case investigations or environmental surveillance in PR for SFR, 28,517 arthropods were collected, including species known or potentially involved in the SFR cycles, such as Amblyomma sculptum, Amblyomma aureolatum, Amblyomma ovale, Amblyomma dubitatum, Amblyomma parkeri, Ctenocephalides felis felis, and Rhipicephalus sanguineus sensu lato. From these Rickettsia asembonensis, Rickettsia bellii, Rickettsia felis, Rickettsia parkeri strain Atlantic Rainforest and Candidatus Rickettsia paranaensis were detected. Ectoparasite abundance was found to be related with specific hosts and collection environments. Rickettsiae circulation was observed for 48 municipalities, encompassing 16 Health Regions (HR). As for socio-demographic and assistance indicators, circulation occurred largely in the most urbanized HR, with a higher per capita Gross Domestic Product, lower Family Health Strategy coverage, and with a higher ratio of beds in the Unified Health System per thousand inhabitants. For environmental variables, circulation occurred predominantly in HR with a climatic classified as "subtropical with hot summers" (Cfa), and with forest type phytogeographic formations. In terms of land use, circulation was commonest in areas with agriculture, pasture and fields and forest cover. Rickettsiae were circulating in almost all hydrographic basins of PR state. The results of this study provide the first descriptive recognition of SFR in PR, as well as outlining its eco-epidemiological dynamics. These proved to be quite heterogeneous, and analyzed scenarios showed characteristics strongly-associated with the outbreaks, with cases presenting clinical variation in space, so illustrating the complexity of scenarios in PR state. Due to the diversity of the circumstances surrounding SFR infections in PR, public health initiatives are necessary to foster a better understanding of the dynamics and factors effecting vulnerability to SFR in this Brazilian state.


Assuntos
Ixodidae , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Animais , Biodiversidade , Brasil/epidemiologia , Humanos , Rickettsia/genética , Rickettsiose do Grupo da Febre Maculosa/epidemiologia
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