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1.
Clin Microbiol Rev ; : e0009724, 2024 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-39494872

RESUMEN

SUMMARYLyme borreliosis or Lyme disease is the most frequently reported tick-borne disease in the Northern Hemisphere. In countries of the Southern Hemisphere, such as Brazil, since the early 1990s, some researchers have argued for the existence of an autochthonous Lyme-like borreliosis, known locally as the Baggio-Yoshinari syndrome (BYS), an alleged "Brazilian borreliosis" supposedly caused by a different strain of Borrelia burgdorferi and transmitted by hard ticks. Currently, the existence of BYS in Brazil is still accepted by a large part of the human health care workers, scientists, medical societies, and patients. In fact, this alleged "Brazilian borreliosis" has been the tick-borne zoonotic disease with the greatest number of reported cases and published studies in Brazil during this century, second only to Brazilian spotted fever. In this manuscript, we reviewed all manuscripts directly related to BYS that have been published in Brazil during the last 35 years. This analysis included 199 individual human cases that have been reported in Brazil since 1989, plus multiple studies on ticks, domestic, and wild animals. Our revision aimed to provide a critical opinion on whether the current published works allow healthcare workers, public health agencies, and patients to accept the existence of Lyme disease, BYS, or other Lyme borreliosis-related disease in Brazil. For this purpose, we evaluated the strengths and weaknesses of each published study, considering the diagnostic methods used, such as serological, microbiological, and molecular analyses. Based on these evaluations, we conclude that there is not enough evidence to support the occurrence of Lyme borreliosis in Brazil or that BYS (Brazilian Lyme-like disease) is caused by a bacterium of the genus Borrelia. This assumption is based on the inaccuracy, unreliability, and misinterpretation of the different diagnostic methods that have been used in Brazil. Recognizing the lack of technical evidence for the occurrence of Lyme borreliosis in Brazil has highly relevant implications. For example, it becomes imperative to raise awareness among the country's medical profession, as they have adopted unnecessary and extreme therapies recommended for patients with a supposed borrelial infection, including BYS, in Brazil. Finally, the technical analyses carried out in this study could be applied to other countries in the Southern Hemisphere (e.g., Argentina, South Africa, Australia), where cases classified and alleged as Lyme disease have been reported.

2.
Parasitol Res ; 123(7): 264, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980469

RESUMEN

Ticks are ectoparasite vectors of pathogens affecting human and animal health worldwide. Rational integration of different control interventions including plant-derived repellents and acaricides, management of natural predators, and vaccines is required for innovative approaches to reduce the risks associated with ticks and tick-borne diseases. How tick populations are naturally controlled is always a question. Tick interactions with other arthropods including predators evolved from ancient times. In this study, Cretaceous (ca. 100 Mya) Burmese amber inclusions were identified as probably related to Compluriscutula vetulum (Acari: Ixodida: Ixodidae) tick larvae and spider silk. As illustrated in this study, ancient interactions between ticks and spiders may support arthropod predatory behavior as a natural control intervention. Rational integrative management of different tick control interventions including natural predators under a One Health perspective will contribute to effectively and sustainably reducing the risks associated with ticks and tick-borne diseases.


Asunto(s)
Conducta Predatoria , Arañas , Animales , Arañas/fisiología , Ixodidae/fisiología , Larva/fisiología
3.
Exp Appl Acarol ; 92(3): 463-477, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38361037

RESUMEN

Ticks are hematophagous arthropods and, during feeding, may transmit pathogens to vertebrate hosts, including humans. This study aimed to investigate the presence of Rickettsia spp. in ticks collected between 2010 and 2013 from free-ranging capybaras (Hydrochoerus hydrochaeris) and opossums (Didelphis albiventris) that inhabit Sabiá Park in Uberlândia, Brazil. Overall, 1,860 ticks were collected: 1,272 (68.4%) from capybaras (487 of the species Amblyomma sculptum, 475 adults and 12 nymphs; 778 Amblyomma dubitatum, 727 adults and 51 nymphs; and seven larva clusters of the genus Amblyomma); and 588 (31.6%) from opossums (21 A. sculptum, one adult and 20 nymphs; 79 A. dubitatum, all nymphs; 15 Ixodes loricatus, 12 adults and three nymphs; 457 Amblyomma sp. larva clusters; 15 Ixodes sp. larva clusters; and one Argasidae larva cluster). Out of 201 DNA samples tested for the presence of Rickettsia spp. DNA using polymerase chain reaction (PCR) 12 showed amplification of a gtlA gene segment that was specific to Rickettsia bellii, a bacterium non-pathogenic to humans. As there has been a report showing serological evidence of infections caused by Rickettsia species of the spotted fever group (SFG) in capybaras and opossums in the park, including Rickettsia rickettsii, the etiological agent of Brazilian spotted fever, and considering the presence of A. sculptum ticks, which are aggressive to humans, as well as these vertebrate hosts, which are amplifiers of R. rickettsii, it is important to monitor the presence of SFG rickettsiae in the Sabiá Park, which is visited daily by thousands of people.


Asunto(s)
Didelphis , Ixodidae , Larva , Ninfa , Rickettsia , Animales , Brasil , Rickettsia/aislamiento & purificación , Ninfa/crecimiento & desarrollo , Ninfa/microbiología , Ninfa/fisiología , Larva/microbiología , Larva/crecimiento & desarrollo , Larva/fisiología , Ixodidae/microbiología , Ixodidae/crecimiento & desarrollo , Ixodidae/fisiología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/epidemiología , Femenino , Parques Recreativos , Amblyomma/microbiología , Amblyomma/crecimiento & desarrollo , Masculino , Roedores/parasitología , Zarigüeyas/parasitología
4.
Exp Appl Acarol ; 91(2): 339-358, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37768388

RESUMEN

We report Rickettsia species from 2,334 ticks collected from environment (1,939 ticks) and animals (395 ticks) in the largest inland fragment of the Atlantic rainforest of southern Brazil and its fragments. Additionally, the DNA infection rates of Amblyomma ovale tick populations in the Neotropics with Rickettsia bellii and Rickettsia parkeri strain Atlantic rainforest were calculated using data from scientific publications, and their correlation was evaluated. From 11 tick species Rickettsia DNA was detected in seven (Amblyomma brasiliense, Amblyomma coelebs, Amblyomma incisum, Amblyomma longirostre, A. ovale, Haemaphysalis juxtakochi, Ixodes fuscipes) and was not detected in four species (Amblyomma dubitatum, Ixodes loricatus, Rhipicephalus microplus and Rhipicephalus sanguineus sensu lato). DNA of five Rickettsia species was detected (R. bellii, Rickettsia amblyommatis, Rickettsia rhipicephali, Rickettsia felis and Rickettsia sp. Aragaoi). To determine the prevalence of Rickettsia DNA positivity according to vector species, ticks were processed individually or in pools of 2-10 individuals (samples). The most prevalent Rickettsia species was R. bellii, found in 112 samples, followed by R. amblyommatis, R. rhipicephali, R. felis and Rickettsia sp. Aragaoi, found in 16, five, two and one sample, respectively. Rickettsia bellii DNA was found in five tick species with the highest infection rate in A. ovale and A. brasiliense. Absence of R. parkeri strain Atlantic rainforest in A. ovale ticks was an unexpected result. Furthermore, a negative correlation was identified between the infection rates (DNA) of R. bellii and/or R. parkeri strain Atlantic rainforest within A. ovale tick populations in the Neotropics. Putting together current knowledge, it can be proposed that, within natural settings, the diversity of rickettsiae and ticks creates a buffering effect on the overgrowth of rickettsiae and episodes of bacteremia in the hosts.

5.
Exp Appl Acarol ; 89(2): 317-327, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36795267

RESUMEN

Rickettsia rickettsii is the etiological agent of Rocky Mountain spotted fever, which is an important tick-borne zoonosis and, in Brazil, it causes Brazilian spotted fever, which has high lethality rate. This study aimed to evaluate a synthetic peptide corresponding to a segment of the outer membrane protein A (OmpA) as an antigen in a serological test for the diagnosis of rickettsial infections. The amino acid sequence of the peptide was selected by predicting B cell epitopes using B Cell Epitope Prediction (Immune Epitope Database and Analysis Resource) and Epitopia and OmpA sequences of Rickettsia rickettsii strain 'Brazil' and Rickettsia parkeri strains 'Maculatum 20' and 'Portsmouth'. A peptide with amino acid sequence common to both Rickettsia species was synthesized and arbitrarily named OmpA-pLMC. To evaluate this peptide in enzyme-linked immunosorbent assay (ELISA), serum samples of capybara (Hydrochoerus hydrochaeris), horse (Equus caballus), and opossum (Didelphis albiventris) that had been previously tested by indirect immunofluorescence assay (IFA) for rickettsial infection were separated into IFA-positive and IFA-negative groups and used in the assay. There were no significant differences in ELISA optical density (OD) values between IFA-positive and IFA-negative groups with horse samples. The mean OD values were significantly higher in the IFA-positive capybara serum samples (IFA-pos vs. IFA-neg = 2.389 ± 0.761 vs. 1.760 ± 0.840). However, receiver operating characteristic (ROC) curve analysis did not show significant diagnostic parameters. On the other hand, 12 out of 14 (85.7%) opossum samples of the IFA-positive group showed reactivity in ELISA, and this was significantly higher than of the IFA-negative group (0.7196 ± 0.440 vs. 0.2318 ± 0.098, respectively; 85.7% sensitivity, 100% specificity). Therefore, our results show that OmpA-pLMC has a potential to be used in immunodiagnostic assays to detect spotted fever group rickettsial infections.


Asunto(s)
Didelphis , Enfermedades de los Caballos , Infecciones por Rickettsia , Rickettsia , Fiebre Maculosa de las Montañas Rocosas , Enfermedades de los Roedores , Caballos , Animales , Roedores , Infecciones por Rickettsia/diagnóstico , Infecciones por Rickettsia/veterinaria , Fiebre Maculosa de las Montañas Rocosas/microbiología , Fiebre Maculosa de las Montañas Rocosas/veterinaria , Rickettsia rickettsii , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de los Caballos/diagnóstico , Enfermedades de los Roedores/microbiología
6.
Exp Appl Acarol ; 86(3): 455-463, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35235094

RESUMEN

Rickettsia rickettsii infection causes the highest human fatality rate among all Rickettsia species of the world and is endemic in Southeast Brazil. In this part of the country most human spotted fever cases are related to unnaturally high populations of ticks, usually a mix of two species, Amblyomma dubitatum Neumann and Amblyomma sculptum Berlese and their local host, capybara (Hydrochoerus hydrochaeris). At the same time, an increase in the number of SF notifications as well as its urbanization was observed, and a better characterization of disease epidemiology is mandatory for control measures and to halt its expansion. It was recently noticed in southeast Brazil that SF endemic areas were characterized by overgrowth populations of A. sculptum and decreased populations of A. dubitatum. Hence, characterization of areas with potential to endemicity, eco-epidemiological studies and control measures may rely on the evaluation of A. sculptum/A. dubitatum rate. However, in potentially endemic scenarios, discriminating the two tick species, particularly the nymphs considered the main vector stage, is a challenge in face of several hundreds to thousands of ticks that should be examined for quantitative studies. We herein present additional morphological features to an existing identification key for Amblyomma nymphs that considerably diminishes the labor to distinguish nymphs of these two tick species. Specifically, the oval-shaped scutum of A. dubitatum and a conspicuous scapula of A. sculptum are prominent discriminating features.


Asunto(s)
Ixodidae , Rickettsia , Garrapatas , Amblyomma , Animales , Brasil/epidemiología , Diagnóstico Diferencial , Ixodidae/microbiología , Escápula
7.
Emerg Infect Dis ; 27(4): 1177-1180, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33754985

RESUMEN

We obtained the complete sequence of a novel poxvirus, tentatively named Brazilian porcupinepox virus, from a wild porcupine (Coendou prehensilis) in Brazil that had skin and internal lesions characteristic of poxvirus infection. The impact of this lethal poxvirus on the survival of this species and its potential zoonotic importance remain to be investigated.


Asunto(s)
Infecciones por Poxviridae , Poxviridae , Brasil , Genómica , Humanos , Filogenia
8.
Exp Appl Acarol ; 84(3): 659-672, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34138398

RESUMEN

We herein describe zebuine cattle tick infestation in a farm in southeast Brazil with an examination accurate enough to detect tick immatures and species other than R. microplus. Cattle were inspected monthly for ticks from May 2015 to May 2017 and 7604 ticks were collected along 276 bovine inspections. Rhipicephalus microplus was the dominant species (7197 specimens, 94.5% from the total), but Amblyomma sculptum was also collected (407/5.5%). Horse tick infestations were evaluated for comparison purposes of A. sculptum infestations of a primary host sharing pastures with bovines. Ticks were counted on the left side of 4-12 horses every 3 months from October 2015 to October 2017. Overall, 68 horse inspections were performed and 1702 ticks were collected: Dermacentor nitens (805 specimens/47.3% of the total), A. sculptum (733/43.1%) and R. microplus (164/9.6%). Overall mean tick abundance on bovines was low if compared to that of taurine cattle and counting revealed four annual generations of R. microplus. The interval between infestation peaks was 3 months, irrespective of the season, and an increase in tick counts from spring onward, as described in the south of Brazil, was not seen. Amblyomma sculptum infestation abundance was minor but constant and in high prevalence. Cattle infestation with A. sculptum seems to depend on pasture sharing with other domestic and wild hosts that are its primary hosts and provide engorged females to complete their life cycle. The impact of such tick sharing among several host species on tick-borne pathogen transmission remains to be elucidated.


Asunto(s)
Enfermedades de los Bovinos , Ixodidae , Rhipicephalus , Infestaciones por Garrapatas , Amblyomma , Animales , Brasil/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Granjas , Femenino , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/veterinaria
9.
Exp Appl Acarol ; 83(4): 555-573, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33779896

RESUMEN

Rondônia is the only state in the North Region of Brazil to have registered confirmed cases of Brazilian Spotted Fever (BSF). The present study investigated the epidemiological cycle of Rickettsia spp. by surveying free-living ixodofauna and tick parasitism of dogs in the municipality of Porto Velho, Rondônia State. Ticks and dogs were tested for the presence of Rickettsia spp. DNA and dog serum was tested for reactivity to anti-Rickettsia spp. antibodies. Tick collection and dog blood sampling were performed in peri-urban and rural environments at 11 locations. Eight free-living Amblyomma species and one Haemaphysalis species were collected: A. scalpturatum, A. naponense, A. oblongoguttatum, A. coelebs, A. latepunctatum, A. pacae, A. ovale, Amblyomma sp., and H. juxtakochi. Three tick species were found parasitizing dogs: Rhipicephalus sanguineus sensu lato, A. oblongoguttatum and A. ovale. Molecular analysis did not identify the presence of the gltA gene fragment in any tick specimen. Results from an indirect immunofluorescent assay (IFA) showed that 20.8% of peri-urban and 15.4% of rural dog sera exhibited reactivity to Rickettsia rhipicephali, Rickettsia amblyommatis, Rickettsia bellii and Rickettsia parkeri antigens. Antibody prevalence in dogs was 16.4%. This study is the first to describe the prevalence of Rickettsia spp. infection in dogs from Porto Velho municipality. Our findings enhance current knowledge of Rickettsia spp. circulation in the Western Amazon.


Asunto(s)
Enfermedades de los Perros , Rickettsia , Rickettsiosis Exantemáticas , Garrapatas , Animales , Brasil/epidemiología , Enfermedades de los Perros/epidemiología , Perros
10.
Exp Appl Acarol ; 79(3-4): 405-410, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31792751

RESUMEN

Environmental distribution of the two most abundant ticks in forest areas in the Brazilian Pantanal was evaluated by CO2 traps methodology in the wet season (peak of adult ticks) of 2012 and 2013. Adults of Amblyomma parvum were concentrated inside agglomerates of Bromelia balansae, in the border of forest patches. Adults of Amblyomma sculptum occurred in similar numbers both in bromeliad clumps and in bromeliad-free areas. Differential distribution of ticks in this habitat could be associated to the frequent use of bromeliad clumps by wild animals (potential hosts) and to the microclimate conditions inside this vegetation in the Pantanal. It is important to verify whether larvae and nymphs of A. parvum have a similar pattern of distribution in the same areas, during the dry season. These stages are more susceptible to desiccation and their principal hosts, non-volant small mammals, also use these bromeliad areas.


Asunto(s)
Distribución Animal , Bosques , Ixodidae , Animales , Brasil , Bromeliaceae , Ninfa
11.
Acta Vet Hung ; 67(1): 81-86, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30922093

RESUMEN

At clinical examination, a 5-year-old male domestic short-haired cat exhibited painful swelling and erythema of the pinnae of both ears. Microscopically, the lesions on both pinnae were composed of diffuse granulomatous chondritis with degeneration and necrosis of the pinnal cartilage. Numerous mast cells were also observed within and surrounding the inflammatory lesion. Immunohistochemistry showed a mixed inflammatory infiltrate characterised by the predominance of macrophages (CD68+, MAC 387+ and Lysozyme+), T lymphocytes (CD3+), some B lymphocytes (CD79α+) and neutrophils. Immunopathological characterisation of the lesion showed a granulomatous inflammation profile and suggests that the morphological changes and immunopathogenesis of auricular chondritis in cats presents a similarity with relapsing polychondritis in humans.


Asunto(s)
Enfermedades de los Gatos/patología , Pabellón Auricular/patología , Síndrome de Tietze/veterinaria , Animales , Enfermedades de los Gatos/inmunología , Gatos , Masculino , Síndrome de Tietze/patología
12.
Exp Appl Acarol ; 76(4): 507-512, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30421132

RESUMEN

Amblyomma parvum Aragão (Acari: Ixodidae) is a tick species found with wide distribution in the Neotropical region. Even though it is a wildlife-related tick, it is also a frequent parasite of domestic animals, is aggressive to human beings and may harbor pathogenic microorganisms. Therefore, it is a target species for control on domestic animals, particularly those at the rural-wildlife interface. Herein, the efficacy of two isolates (E9 and IBCB 425) of an entomopathogenic fungus, Metarhizium anisopliae sensu lato, already evaluated for ticks that parasitize domestic animals, was tested against unfed A. parvum adults. Both isolates displayed high acaricidal efficacy after immersion in fungal conidial suspensions for 5 min. Isolate E9 killed all ticks by the 7th day post-treatment, and isolate IBCB 425 did so by the 11th day. Tick mortality of 80 and 90% was achieved as early as the 3rd and 4th days, respectively, with both treatments. Thus, if a commercial M. anisopliae s.l. acaricide against domestic animal ticks is developed, it would also be effective against A. parvum.


Asunto(s)
Ixodidae/microbiología , Metarhizium/fisiología , Control Biológico de Vectores , Control de Ácaros y Garrapatas , Animales , Femenino , Masculino
13.
Exp Appl Acarol ; 76(3): 381-397, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30317459

RESUMEN

The Cerrado Biome is the second largest in Brazil covering roughly 2 million km2, with varying features throughout its area. The Biome is endangered but it is also source of animal species for rural, green urban and degraded rainforest areas. Ticks are among Cerrado species that establish at anthropogenic sites and although information about them is steadily increasing, several features are unknown. We herein report tick species, abundance and some ecological relationships within natural areas of the Cerrado at higher altitudes (800-1500 m) within and around Serra da Canastra National Park, in Minas Gerais State Brazil. In total of 1196 ticks were collected in the environment along 10 campaigns held in 3 years (2007-2009). Amblyomma sculptum was the most numerous species followed by Amblyomma dubitatum and Amblyomma brasiliense. Distribution of these species was very uneven and an established population of A. brasiliense in the Cerrado is reported for the first time. Other tick species (Amblyomma ovale, Amblyomma nodosum, Amblyomma parvum, Ixodes schulzei and Haemaphysalis leporispalustris) were found in lesser numbers. Domestic animals displayed tick infestations of both rural and urban origin as well as from natural areas (Rhipicephalus sanguineus sensu lato, Rhipicephalus microplus, Dermacentor nitens, A. sculptum, A. ovale, Amblyomma tigrinum, Argas miniatus). Amblyomma sculptum had the widest domestic host spectrum among all tick species. DNA of only one Rickettsia species, R. bellii, was found in an A. dubitatum tick. Several biological and ecological features of ticks of the studied areas are discussed.


Asunto(s)
Biodiversidad , Ixodidae/fisiología , Rickettsia/aislamiento & purificación , Animales , Brasil , ADN Bacteriano/análisis , Femenino , Ixodidae/clasificación , Ixodidae/crecimiento & desarrollo , Ixodidae/microbiología , Larva/clasificación , Larva/fisiología , Masculino , Ninfa/clasificación , Ninfa/fisiología , Parques Recreativos , Dinámica Poblacional , ARN Ribosómico 16S/análisis , Rickettsia/clasificación , Estaciones del Año , Análisis de Secuencia de ADN
14.
Arch Virol ; 162(6): 1783-1786, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28220327

RESUMEN

Cacipacoré virus (CPCV) is a potential emerging virus classified in the genus Flavivirus, family Flaviviridae. In the present study, we present the genetic characterization of a CPCV isolated from ticks (Amblyomma cajennense) collected from a sick capybara (Hydrochoerus hydrochaeris) in São Paulo State, Brazil. The CPCV isolate shares the typical genomic organization of flaviviruses with 10,857 nucleotides in length and a single open reading frame of 10,284 nucleotides encoding a polyprotein of 3,427 amino acids. Phylogenetic analysis revealed that CPCV is unique, as a potentially tick-borne virus, in the Japanese encephalitis virus serogroup.


Asunto(s)
Vectores Arácnidos/virología , Infecciones por Flavivirus/veterinaria , Flavivirus/genética , Flavivirus/aislamiento & purificación , Enfermedades de los Roedores/virología , Garrapatas/virología , Animales , Brasil , Flavivirus/clasificación , Infecciones por Flavivirus/transmisión , Infecciones por Flavivirus/virología , Genoma Viral , Filogenia , Enfermedades de los Roedores/transmisión , Roedores , Proteínas Virales/genética
15.
Exp Appl Acarol ; 68(2): 227-40, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26613758

RESUMEN

Pantanal is a huge floodplain mostly in Brazil, and its main economic activity is extensive cattle raising, in farms characterized by an extremely wildlife-rich environment. We herein describe tick infestations of cattle and of the natural environment in Pantanal of Nhecolândia in Brazil, at areas with and without cattle during both dry and wet seasons. Environmental sampling resulted in three tick species: Amblyomma sculptum (423 nymphs and 518 adults), Amblyomma parvum (7 nymphs and 129 adults), Amblyomma ovale (3 adults) as well as three clusters and two individuals of Amblyomma sp. larvae. A significantly higher number of adult A. sculptum ticks was found in areas with cattle in the wet season. From 106 examinations of bovines 1710 ticks from three species were collected: Rhipicephalus microplus (55.7% of the total), A. sculptum (38%) and A. parvum (4.1%), as well as 32 Amblyomma sp. larvae. A significant similarity was found between Amblyomma tick fauna from environment and on cattle during both seasons. All A. sculptum females on bovines were flat whereas many of A. parvum females and A. sculptum nymphs were engorging. Although R. microplus was the most abundant tick species on cattle, overall highest tick prevalence on bovines in the dry season was of A. sculptum nymphs. Lack of R. microplus in environmental sampling, relationship between cattle and increase in adult A. sculptum numbers in the environment as well as suitability of bovine for the various tick species are discussed.


Asunto(s)
Bovinos/parasitología , Infestaciones por Garrapatas/veterinaria , Animales , Brasil , Ecosistema , Femenino , Masculino , Estaciones del Año , Infestaciones por Garrapatas/parasitología , Garrapatas
16.
Exp Appl Acarol ; 70(4): 483-489, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27815656

RESUMEN

Ticks from Rhipicephalus sanguineus complex are widely distributed in the world and one species from this complex is the most common tick on dogs in Brazil, notably in urban areas. This tick is a vector of several diseases. Among others it transmits the agent of canine Ehrlichiosis, a major dog infectious disease and the agent of Rocky Mountain spotted fever. This tick can spread rapidly and develop intolerable infestations within no time. Currently tick control is done with acaricides and demand for such drugs has grown fast. However, R. sanguineus has already developed resistance to the main active compounds and the development of new acaricides is necessary. Many essential oils of plants have acaricidal effect and may be an important source of molecules for the synthesis of new acaricide products. In this study, we evaluated the effectiveness of a new herbal phytotherapic, consisting of the essential oil of Tagetes minuta L., against R. sanguineus in vitro and on dogs undergoing experimental infestations. The product displayed 100% efficacy against larvae, nymphs and adults of the tick on all tested conditions.


Asunto(s)
Enfermedades de los Perros/tratamiento farmacológico , Aceites Volátiles/farmacología , Aceites Volátiles/uso terapéutico , Rhipicephalus sanguineus/efectos de los fármacos , Tagetes/química , Control de Ácaros y Garrapatas , Infestaciones por Garrapatas/veterinaria , Acaricidas/farmacología , Acaricidas/uso terapéutico , Animales , Brasil , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/prevención & control , Perros , Femenino , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Masculino , Ninfa/efectos de los fármacos , Ninfa/crecimiento & desarrollo , Rhipicephalus sanguineus/crecimiento & desarrollo , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/parasitología , Infestaciones por Garrapatas/prevención & control
17.
J Med Entomol ; 52(2): 117-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26336294

RESUMEN

Identifying the tick species that successfully feed on humans would increase knowledge of the epidemiology of several tick-borne diseases. These species salivate into the host, increasing the risk of pathogen transmission. However, there is a lack of data in the literature regarding the ticks that prefer to feed on humans. Herein, we describe the successful feeding of Amblyomma coelebs Neumann nymphs on two of the authors after accidental tick bites occurred during field surveys in two preserved areas of Mato Grosso do Sul, Brazil. One of the host-parasite interactions was closely monitored, and the tick development, gross host skin alterations, and related sensations are presented.


Asunto(s)
Ixodidae , Piel/patología , Mordeduras de Garrapatas/patología , Animales , Conducta Alimentaria , Humanos , Ninfa
18.
Exp Appl Acarol ; 64(3): 393-406, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25037743

RESUMEN

The Pantanal in Brazil is the largest floodplain of the world. This ecosystem, rich in wildlife, has a large feral pig population. Such a large host biomass must have a strong influence on the parasite fauna. In this work, we evaluated the role of feral pigs in the maintenance of Amblyomma sculptum (formerly Amblyomma cajennense), the most prevalent tick species in the Pantanal. Tick infestations were evaluated on 243 feral pigs and their environment. The suitability of domestic pigs, representing their feral relatives, to A. sculptum adults and nymphs was assessed experimentally. Tick infestation of feral pigs was strongly associated with that of the environment: 96 and 97 % of the ticks, respectively, were A. sculptum. The infestation prevalence on this host species was close to 90 % in the dry season and 100 % in the wet season and mean infestation intensity was above 30 ticks in both seasons. Suitability of pigs as hosts for A. sculptum was shown by the high proportion of nymphs and female ticks found engorging on captured feral pigs and adequate biological parameters displayed by ticks from experimental infestations of domestic pigs. Other tick species on feral pigs, albeit in much lower numbers, were Amblyomma parvum and Ornithodorus rostratus. Results show that feral pigs feed a high proportion of the A. sculptum adults and nymphs in their territories and should be a target for tick-borne diseases studies. This is particularly relevant to public health because all the main tick species found on feral pigs are aggressive to humans as well.


Asunto(s)
Interacciones Huésped-Parásitos , Ixodidae/fisiología , Porcinos/parasitología , Infestaciones por Garrapatas/veterinaria , Animales , Brasil , Conducta Alimentaria , Femenino , Ixodidae/crecimiento & desarrollo , Ninfa/fisiología , Densidad de Población , Prevalencia , Infestaciones por Garrapatas/epidemiología
19.
Exp Appl Acarol ; 64(2): 259-63, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24696361

RESUMEN

Brazil harbors five species of Cypseloidinae swifts. Those from Streptoprocne and Cypseloides genera have a very distinct ecology. They shelter at night and build nests in moist cliffs by waterfalls. Information about tick infestation of these birds is virtually non-existent and restricted to the description of a new species, Ixodes paranaensis, in Streptoprocne biscutata in Paraná State and another record of this species in Streptoprocne zonaris in Minas Gerais State. We herein report tick infestation of swifts at eight waterfalls in the Cerrado biome of Minas Gerais State, southeastern Brazil. Swifts were captured during six campaigns from November 2008 to April 2013. Overall, 584 swifts were captured (527 C. senex, four C. fumigatus and 53 S. zonaris). Four birds were tick infested (prevalence of 0.7 %). Three individuals of C. senex hosted one tick each; a nymph of I. paranaensis, a female of I. paranaensis and a nymph of Amblyomma cajennense. One S. zonaris hosted an I. paranaensis nymph and an Ornithodoros sp. larva (Argasidae).


Asunto(s)
Enfermedades de las Aves/parasitología , Ixodidae/clasificación , Infestaciones por Garrapatas/veterinaria , Animales , Enfermedades de las Aves/epidemiología , Aves , Brasil/epidemiología , Femenino , Especificidad de la Especie , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
20.
Vet Parasitol Reg Stud Reports ; 50: 101016, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38644046

RESUMEN

Wild boars or feral pigs are classified by the Brazilian Institute for the Environment and Renewable Resources (IBAMA) in "Category I of invasive exotic species". They cause economic losses, harm the environment, serve as hosts and reservoirs for several zoonotic disease agents, and provide a blood meal for tick species that act as vectors for zoonotic diseases. The objective of this study was to identify tick species on wild boars, assess host-seeking ticks in the related environment, and identify other potential tick hosts coexisting with wild boars on a farm located in the state of Minas Gerais, southeastern Brazil. Additionally, the study aimed to determine the presence of rickettsiae in these arthropods and assess the exposure of wild boars to rickettsiae species from the Spotted Fever Group and Rickettsia bellii through serology. A total of 3585 host-seeking ticks from three species (Amblyomma sculptum - 41.58%; Amblyomma dubitatum - 0.39% and Rhipicephalus microplus - 0.05%) were collected in the environment and A. sculptum was the most abundant species. Thirty-one wild boars were evaluated, resulting in the collection of 415 ticks, all of which were A. sculptum. Rickettsia DNA was not detected in samples of A. sculptum and R. microplus from the environment or in A. sculptum ticks from wild boars. However, all A. dubitatum ticks (n = 14) had Rickettsia bellii DNA confirmed by the species-specific PCR protocol. Out of the 31 serum samples from wild boars, 24 reacted with at least one Rickettsia antigen. Among these, seven individuals exhibited a reaction to a probable homologous antigen (PHA) of three rickettsiae species: R. rickettsii (n = 3), R. amblyommatis (n = 3) and R. rhipicephali (n = 1). Despite the high prevalence of seroreactivity, titers were low, indicating limited exposure to Rickettsia spp. Camera traps generated 874 animal records, capturing a total of 1688 individuals. At least 11 species of birds and 14 species of mammals (12 wild and two domestic) shared the environment with wild boars and potentially shared ticks with them. These findings provide baseline information for understanding the sharing of ticks and tick-borne pathogens between wild boars and other animals within the Cerrado biome. Further studies are necessary to monitor the potential and actual risk of wild boars to harbor infected ticks and their role in the transmission and maintenance cycle of Rickettsia spp.


Asunto(s)
Infecciones por Rickettsia , Rickettsia , Sus scrofa , Enfermedades de los Porcinos , Infestaciones por Garrapatas , Animales , Brasil/epidemiología , Rickettsia/aislamiento & purificación , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/parasitología , Enfermedades de los Porcinos/microbiología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología , Infecciones por Rickettsia/veterinaria , Infecciones por Rickettsia/epidemiología , Infecciones por Rickettsia/microbiología , Infecciones por Rickettsia/transmisión , Femenino , Masculino , Ixodidae/microbiología , Amblyomma/microbiología , Rhipicephalus/microbiología
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