Effect of environmental variables on the abundance of Amblyomma ticks, potential vectors of Rickettsia parkeri in central Brazil.

Amblyomma ticks are vectors of both Rickettsia rickettsii and R. parkeri in the Americas, where capybaras (Hydrochoerus hydrochaeris) are the main hosts in urban areas, thus contributing to the transmission of spotted fever. Herein, we studied: (i) the seasonal dynamics and abundance of ticks in areas where capybaras live, (ii) the effect of environmental variables on tick abundance, and (iii) the presence of Rickettsia-infected ticks. Between September 2021 and September 2022, we sampled ticks using cloth-dragging at 194 sites on the shore of Lake Paranoá in Brasília, Brazil. We measured environmental data (season, vegetation type, canopy density, temperature, humidity, and presence or vestige of capybara) at each site. Nymphs and adults were morphologically identified to the species level, and a selected tick sample including larvae was subjected to genotypic identification. We investigated Rickettsia-infected ticks by PCR (gltA, htrA, ompB, and ompA genes) and associations between tick abundance and environmental variables using Generalized Linear Models. A total of 30,334 ticks (96% larvae) were captured. Ticks were identified as Amblyomma, with A. sculptum comprising 97% of the adult/nymphs. Genotype identification of a larval sample confirmed that 95% belonged to A. dubitatum. Seasonal variables showed significant effects on tick abundance. Most larvae and nymphs were captured during the early dry season, while the adults were more abundant during the wet season. Vegetation variables and the presence of capybaras showed no association with tick abundance. Rickettsia parkeri group and R. bellii were identified in A. dubitatum, while A. sculptum presented R. bellii. We conclude that: (i) Amblyomma ticks are widely distributed in Lake Paranoá throughout the year, especially larvae at the dry season, (ii) the abundance of Amblyomma ticks is explained more by climatic factors than by vegetation or presence of capybaras, and (iii) A. dubitatum ticks are potential vectors of R. parkeri in Brasília.

Epidemiological analysis of Dirofilaria immitis (Spirurida: Onchocercidae) infecting pet dogs (Canis lupus familiaris, Linnaeus, 1758) in Baixada Fluminense, Rio de Janeiro.

Dirofilaria immitis infection is routinely detected in dogs during veterinary care in tropical and subtropical regions worldwide. Parasitological tests for the detection of this infection are routinely performed only in areas with a high prevalence. Baixada Fluminense, a region in Rio de Janeiro, was considered heartworm-free until local veterinarians began to receive blood exams results indicating the presence of microfilariae (MF). A laboratory database was hence used to collect data from 2017 to 2020 to understand the extent of spread of the parasite in this area. The results of complete blood count analysis and MF or heartworm antigen detection tests conducted on canine samples sent from veterinary clinics in Baixada Fluminense (Magé, Duque de Caxias, Guapimirim, Nova Iguaçu, and São João de Meriti municipalities) were included. In total, the results of 16,314 hematological tests were considered. The overall prevalence of D. immitis was 3.4% (554/16,314), considering that only one test result was obtained per animal on the same day. This study is highly relevant because it indicates the spreading geographic distribution of the worms, heightens awareness among local health professionals and the general population, and encourages compliance with prophylactic measures to prevent further spread of parasite.

Piroplasmid Infections Among Domestic Dogs in the Mountain City of Rio de Janeiro, Brazil.

PURPOSE: The aim of the present study was to analyze the frequency of the piroplasmids in blood from dogs and ticks recovered from these animals in Teresópolis city, located in the mountain region of Rio de Janeiro state, Brazil. In addition to the clinical and hematological profile. METHODS: A total of 400 dogs attended in a veterinary clinic in this city between 2020 and 2021 were included. The blood was collected from the dogs, along with ticks and information on these dogs was obtained through a questionnaire applied to the owners. Thin-smear analyses and complete blood counts were performed. All forms characteristic of piroplasmids were measured and classified morphologically. The blood was also subjected to PCR assays based on the genes 18S rRNA and hsp70. In addition, the ixodid ticks were classified morphologically and subjected to PCR for piroplasmids research. The amplified products were sent for gene sequencing. RESULTS: Piroplasmids were detected in 2.3% of the dogs. The variables statistically associated with infections in these animals were hemorrhage/bleeding, jaundice, anisocytosis, activated monocytes and macroplatelets (p ≤ 0.05). Piriform, ring-shaped, oval and aberrant structures were viewed in erythrocytes, neutrophils and monocytes, with lengths greater than and less than 2.5 µm. The nine positive samples from these dogs were characterized as due to Rangelia vitalii. However, one sequence from B. vogeli was detected in a single adult specimen of R. sanguineus. CONCLUSION: Although circulation of two species of piroplasmids potentially infective for domestic dogs has been observed in the mountain city of Rio de Janeiro, infection due to R. vitalii was mostly seen in the dogs of the present study.

Detection of Rickettsia tamurae-like and other spotted fever group rickettsiae in ticks (Acari: Ixodidae) associated with wild birds in the Western Amazon, Brazil.

Ticks are vectors for several pathogens, including bacteria belonging to the Rickettsia genus, such as Rickettsia rickettsii and Rickettsia parkeri, the causative agents of spotted fever. The aim of the present study was to investigate the tick species richness and rickettsial agents associated with wild birds captured in the Humaita Forest Reserve, Acre, in the Western Amazon region. Wild birds were captured with ornithological nets for visual inspection with the purpose of collecting ticks, which were identified through morphological analyses and molecular tests for several genes (12S rDNA, 16S rDNA, gltA, ompA, and sca4). A total of 607 wild birds were captured, 12% of which were parasitized by 268 ticks of the Amblyomma genus, with new host-parasite associations reported for Amblyomma calcaratum, Amblyomma geayi, Amblyomma longirostre, Amblyomma naponense, Amblyomma nodosum, and Amblyomma varium. Of the total ticks collected, 113 were tested for the presence of rickettsial DNA fragments, with 19 testing positive for R. parkeri in A. geayi, Rickettsia tamurae-like in Amblyomma sp., and Rickettsia amblyommatis in A. geayi, A. longirostre, and Amblyomma sp. We detected R. tamurae-like in Amblyomma larvae for the first time in the Western Brazilian Amazon biome, and registered spotted fever group rickettsiae, although the relevance of the detected species in a public health context should be further explored in South America, as well as new host-parasite interactions in this underexplored region.

Estudo descritivo de casos notificados de febre maculosa em São Paulo, Rio de Janeiro e Minas Gerais entre 2007 e 2016 / Descriptive study of reported cases of spotted fever in São Paulo, Rio de Janeiro and Minas Gerais between 2007 and 2016

Resumo Introdução A febre maculosa é uma doença infecciosa aguda causada por bactérias do gênero Rickettsia e transmitida por carrapatos que pode levar à hospitalização e, eventualmente, a óbito por causa de quadros mais graves. Objetivo O objetivo deste artigo foi descrever o cenário epidemiológico da doença nas três unidades federativas de maior número de notificações e óbitos pela doença no Brasil entre 2007 e 2016. Método Estudo epidemiológico descritivo com base nos dados das fichas de investigação para a doença, sendo analisados dados demográficos, geográficos, ambientais e de hospitalização, diagnóstico e desfecho dos casos na área de estudo. Resultados Foram confirmados 953 casos da doença, em sua maioria por critérios laboratoriais, sendo observada maior prevalência entre homens com idade média de 35 anos, pouco relacionados ao ambiente de trabalho, mas amplamente relacionados ao meio urbano. Do total de casos confirmados, 64% pacientes afirmaram ter tido algum contato com carrapato, assim como com cães (36%), capivaras (20%) e equinos (19%). Conclusão Existem questionamentos a respeito da doença que não foram elucidados neste artigo, entretanto abordagens criativas, validadas e ancoradas na associação de áreas de conhecimento distintas poderão dar bons resultados se objetivamente aplicadas em ações estratégicas da gestão da saúde.

Abstract Background Spotted fever is an acute infectious disease caused by bacteria of the genus Rickettsia and transmitted by ticks, which can lead to hospitalization and, eventually, death due to more severe conditions. Objective The purpose of this article was to describe the epidemiological scenario of the disease in the three federal states with the highest number of notifications and deaths due to the disease in Brazil between 2007 and 2016. Method A descriptive epidemiological study was carried out based on data from the investigation forms for the disease, with data being analyzed on demographic, geographic, environmental, and hospitalization, diagnosis, and outcome of cases in the study area. Results 953 cases of the disease were confirmed, mostly by laboratory criteria, with a higher prevalence being observed among men with an average age of 35 years, little related to the work environment, but largely related to the urban environment. Of the total confirmed cases, 64% of patients said that they had had some contact with ticks, as well as with dogs (36%), capybaras (20%), and horses (19%). Conclusion We believe that there are questions about the disease that were not elucidated in this article, however, creative approaches, validated and anchored in the association of different areas of knowledge can give good results if objectively applied in strategic health management actions.

Piroplasm Infection in Domestic Cats in the Mountainous Region of Rio de Janeiro, Brazil.

Piroplasm infections in domestic cats have been reported with increasing frequency in numerous countries. However, in some states of Brazil, little information is available about the occurrence of these parasites. Blood samples were collected from 250 cats treated at a private clinic in the mountainous region of Rio de Janeiro. The samples were each subjected to a blood count, microscopic examination, and molecular research on piroplasms. The animals' clinical histories and epidemiological information were analyzed to identify the risk factors associated with infection. Ticks were recovered during the clinical care and were identified and subjected to molecular analyses to determine the presence of piroplasm DNA. Piroplasms were detected in 2.7% (7/250) of the cats. Nucleotide sequences of Babesia vogeli were identified in six cats, while the Cytauxzoon sp. was identified in one cat. Cats displaying apathy/weakness/prostration and hemorrhage/bleeding were more likely to be infected. In addition, Amblyomma aureolatum was recovered from a cat PCR-negative for piroplasms. This is the first study in Rio de Janeiro that has detected Babesia vogeli in cats. The results obtained here underscore the need for further studies in Rio de Janeiro to investigate the dynamics of such infections and the vectors involved.

Mapping potential risks for the transmission of spotted fever rickettsiosis: The case study from the Rio de Janeiro state, Brazil.

Spotted fever rickettsiosis is a zoonosis transmitted by ticks, having a varied clinical course that can lead to death if not managed properly. In Brazil it is more commonly observed in the Southeast, being an emerging public health problem. Hazard mapping models are common in different areas of knowledge, including public health, as a way of inferring reality and seeking to reduce or prevent damage. The aim of this study is to offer a spatial heuristic methodology for assessing the potential risk of transmission of spotted fever in the Rio de Janeiro state, located in the southeastern region of Brazil. For this, we used geospatial tools associated with eco-epidemiological data related to the clinical profile of the disease. The results achieved were substantially encouraging, considering that there are territories with greater or lesser expectation of risk for spotted fever in the study area. We observed that there are important distinctions between the two rickettsiosis scenarios in the same geographic space and that the areas where there is a greater potential risk of contracting rickettsiosis coincide with the administrative regions that concentrated the cases of hospitalization and deaths from the disease, concluding that the scenery found are relevant to the case series for the disease and that the planning of surveillance actions can gain in quality if the use of this spatial analysis tool is incorporated into the routine of local health management.

A new focus of spotted fever caused by Rickettsia parkeri in Brazil.

Spotted fever (SF) is a tick-borne zoonosis caused by bacteria of the genus Rickettsia . The disease varies in severity from mild clinical forms to severe cases. In Brazil, Rickettsia rickettsii SF is the most serious rickettsiosis and can result in death if not diagnosed and treated at the onset of symptoms. The SF mild form is caused by Rickettsia parkeri strain Atlantic Rainforest, and this etiological agent has been reported in the South, Southeast and Northeast regions of the country, in areas of preserved or little antropized Atlantic Rainforest. Amblyomma ovale is the proven vector and dogs are the hosts associated with the bioagent cycle. During a SF case investigation in Paraty municipality, Rio de Janeiro State, an Atlantic Rainforest biome area in Southeastern Brazil, the human pathogen R. parkeri strain Atlantic Rainforest was detected by PCR in a sample of human skin inoculation eschar and in a female A. ovale tick collected from a dog. These results expand the known area of occurrence of this mild form rickettsiosis in Brazil. In addition, the results of the present study indicate the importance of implementing programs to control canine ectoparasites and to raise awareness of the risks of infection, signs and symptoms of SF caused by R. parkeri strain Atlantic Rainforest.

Molecular characterization of canine filarioids in a previously non-endemic area of Rio de Janeiro State, Brazil.

Dirofilaria immitis is the causative agent of canine heartworm disease, a severe health problem in dogs, especially in coastal areas of tropical and subtropical regions of the world. We employed molecular methods to investigate the occurrence of canine infection by filarioids in five municipalities of Baixada Fluminense (Magé, Duque de Caxias, Guapimirim, Nova Iguaçu, and São João de Meriti), a non-endemic area of Rio de Janeiro State, Southeast Brazil. A total of 110 canine blood samples collected from 2017 to 2018 and positive for microfilariae at the modified Knott's test were screened by cPCR targeting DNA fragments of the 12S rDNA gene for filarial nematodes. Seventy-seven samples (70%) tested positive at the molecular analysis. Of these, 72 were identified as D. immitis and 5 (4.5%) as Acanthocheilonema reconditum. Dirofilaria repens was not detected in the studied municipalities of Baixada Fluminense. This is the first record of D. immitis and A. reconditum in the Baixada Fluminense region, Rio de Janeiro State, Brazil. The prevalence of D. immitis cases in the five municipalities suggests the establishment and maintenance of its enzootic cycle in the studied region, which indicate vulnerability to the occurrence of epidemic cycles and, possibly, human cases.

A new focus of spotted fever caused by Rickettsia parkeri in Brazil

ABSTRACT Spotted fever (SF) is a tick-borne zoonosis caused by bacteria of the genus Rickettsia . The disease varies in severity from mild clinical forms to severe cases. In Brazil, Rickettsia rickettsii SF is the most serious rickettsiosis and can result in death if not diagnosed and treated at the onset of symptoms. The SF mild form is caused by Rickettsia parkeri strain Atlantic Rainforest, and this etiological agent has been reported in the South, Southeast and Northeast regions of the country, in areas of preserved or little antropized Atlantic Rainforest. Amblyomma ovale is the proven vector and dogs are the hosts associated with the bioagent cycle. During a SF case investigation in Paraty municipality, Rio de Janeiro State, an Atlantic Rainforest biome area in Southeastern Brazil, the human pathogen R. parkeri strain Atlantic Rainforest was detected by PCR in a sample of human skin inoculation eschar and in a female A. ovale tick collected from a dog. These results expand the known area of occurrence of this mild form rickettsiosis in Brazil. In addition, the results of the present study indicate the importance of implementing programs to control canine ectoparasites and to raise awareness of the risks of infection, signs and symptoms of SF caused by R. parkeri strain Atlantic Rainforest.

Amblyomma aureolatum Genetic Diversity and Population Dynamics Are Not Related to Spotted Fever Epidemiological Scenarios in Brazil.

Regional differences in tick-borne disease epidemiology may be related to biological variations between vector populations. Amblyomma aureolatum (Ixodida: Ixodidae), a neotropical tick, is known from several regions in Brazil. However, only in the metropolitan area of São Paulo (SP) state are there studies that establish its role as a vector of a pathogenic rickettsia (Rickettsia rickettsii). The aim of the study was to analyze the genetic diversity, population dynamics, and rickettsia infection in A. aureolatum populations from different spotted fever scenarios in Brazil. Samples were subjected to DNA extraction, amplification and sequencing of 12S rDNA, cytochrome oxidase subunit II and D-loop mitochondrial markers for tick population analyses, and gltA, htrA, ompA, and ompB genes for rickettsia researches. Of the 7-17 tick haplotypes identified, 5-13 were exclusive to each population and 2-12 for each epidemiological scenario, as well as three haplotypes shared by all populations. Amblyomma aureolatum populations are expanding, and do not appear to be genetically structured vis-a-vis the different epidemiological scenarios studied. Rickettsia bellii (in SP) and Rickettsia felis (in Santa Catarina) were identified as infecting A. aureolatum. No relationship between tick haplotypes and rickettsia types were observed.

Microscopic Detection, Hematological Evaluation and Molecular Characterization of Piroplasms from Naturally Infected Dogs in Rio de Janeiro, Brazil.

PURPOSE: This study aimed to analyze the frequency of piroplasmids in the blood of dogs in Rio de Janeiro, compare the performance of microscopic techniques, assess the risk factors associated with infections and also molecularly and morphologically characterize the piroplasmids identified. METHODS: In all, 407 blood samples were collected from dogs between 2018 and 2019. These were subjected to microscopic parasitological techniques for thin and thick smears, stained with Giemsa and using a rapid staining kit. The slides were read under an optical microscope and the protozoa were characterized morphometrically. In addition, the blood samples were subjected to molecular characterization for diagnosing piroplasmid species using primers that amplified the gene 18S rRNA. RESULTS: Piroplasmids were detected in 38 (9.3%) samples. Of these, 33 samples presented nucleotide sequences compatible with Babesia vogeli. Most of the positive samples were young, male, defined breeds dogs that had been attended in clinics in São Gonçalo city. Thrombocytopenia and leukopenia were the hematological alterations more observed in positive samples, but positive samples without alterations were also detected. The sex was the only variable that showed statistical differences. Males dogs being more often infected than females (p < 0.05). The microscope slides mostly showed piriform and oval merozoites measuring greater than 2.5 µm in length, which were compatible with B. vogeli. However, smaller forms were also identified, thus demonstrating the polymorphic nature of this parasite. CONCLUSION: Babesia vogeli was detected in blood samples from dogs in the metropolitan cities of Rio de Janeiro by molecular techniques in different parasite morphotypes.

Biodiversity of Potential Vectors of Rickettsiae and Epidemiological Mosaic of Spotted Fever in the State of Paraná, Brazil.

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.

Ticks (Parasitiformes: Ixodida) on new world wild primates in Brazil

Brazil concentrates the largest number of primate species in the world. In the present study, an extensive literature review of ticks on New World wild monkeys has been carried out, demonstrating that between the years 1912 to 2018, 182 larvae, 137 nymphs and 31 adult ticks (10 males and 21 females) were collected on 78 primates (from 12 different species) in 28 distinct localities in the Brazilian territory. Additionally, examination of allotments of 11 tick collections of Brazil revealed that from 1919 to 2019, 93 larvae, 91 nymphs and 175 adult ticks (62 males and 113 females) were collected from 100 monkeys (among 20 different species) from 43 localities in distinct Brazilian biomes. Overall, 19 tick species were identified on wild primates in the country: Amblyomma aureolatum (Pallas, 1772), Amblyomma cajennense (Fabricius, 1787) sensu stricto, Amblyomma coelebs Neumann, 1899, Amblyomma dubitatum Neumann, 1899, Amblyomma geayi Neumann, 1899, Amblyomma incisum Neumann, 1906, Amblyomma longirostre (Koch, 1844), Amblyomma naponense (Packard, 1869), Amblyomma nodosum Neumann, 1899, Amblyomma ovale Koch, 1844, Amblyomma parkeri Fonseca & Aragão, 1952, Amblyomma romarioi Martins, Luz & Labruna, 2019, Amblyomma rotundatum Koch, 1844, Amblyomma sculptum Berlese, 1888, Haemaphysalis juxtakochi Cooley, 1946, Ixodes fuscipes Koch, 1844, Rhipicephalus microplus (Canestrini, 1888), Rhipicephalus sanguineus (Latreille, 1806) sensu lato,and Ornithodoros rostratus Aragão, 1911. The presence of A. incisum, A. naponense, A. nodosum, A. rotundatum and I. fuscipes on monkeys is recorded for the first time. Thisresearch is therefore a significant contribution to the knowledge of tick speciesassociated with non-human primates in the Neotropical region.

Molecular evaluation of piroplasms and hematological changes in canine blood stored in a clinical laboratory in Niterói, Rio de Janeiro.

Piroplasm species were analyzed by molecular tools in total 31 blood samples from positive dogs, previously checked by stained slides, stored until DNA extraction between 2016 to 2018 in the laboratory Clinical Analyzes in Niterói, Rio de Janeiro. The piroplasms were identified by PCR, targeting the 18S rRNA gene and sequencing. From the total number of samples only 24 (77.4%) were positive and show adequate nucleotide sequences for interpretation with identity between 93%-100% with Babesia vogeli in compared to the sequences isolated of infected dogs from other states in Brazil deposited on GenBank. Most of dogs infected with B. vogeli had anemia (62.5%) and thrombocytopenia (95.8%). The findings of this study are compatible with previous reports in the literature and highlight B. vogeli as the most incriminated species in canine piroplasmosis in Brazil, and thrombocytopenia the hematological alteration most frequently identified in this infection. It is important to note that this is the first study involving the molecular characterization of piroplasms in the metropolitan region of Rio de Janeiro, based on PCR followed by sequencing.

Hepatozoon Infecting Bats in the Southeastern Brazilian Rainforest.

Tick-borne protozoans of the genus Hepatozoon are obligate hemoparasites that can infect domestic and wild terrestrial vertebrates. Main hepatozoonosis affects canids and involves mainly Hepatozoon canis and Hepatozoon americanum. However, molecular studies revealed the capacity of H. canis to infect a wide range of wild mammals. In July 2018, we conducted an epidemiological survey for tick-borne pathogens in wild hosts, assaying Hepatozoon sp. occurrence in 34 bats captured in different habitats within a conservation unit in the state of Espírito Santo, southeastern Brazil. Blood and spleen tissue DNA samples were submitted to PCR amplifications of Babesia/Theileria and Hepatozoon 18S rRNA gene and 21% (7/34) were positive for Hepatozoon sp. Phylogenetic inferences grouped the obtained sequences from Seba's short-tailed bat (Carollia perspicillata) with the H. canis cluster, and from the great fruit-eating bat (Artibeus lituratus) with rodent-associated Hepatozoon cluster. Further studies are needed to characterize the epidemiological role of Seba's short-tailed bat and the great fruit-eating bat in the wild transmission cycle of these hemoparasites in Brazil.

Ticks (Acari: Ixodidae) on wild raptors in Brazil

This research reports ticks on wild raptors in Brazil. Between the years 1936 and 2019, 127 larvae, 230 nymphs and 34 adult ticks were collected on 92 raptors (among 27 different species) from 35 localities in distinct Brazilian biomes. Additionally, an extensive literature review on ticks on wild raptors has been carried out, demonstrating that from 1993 to 2016, 29 larvae, 81 nymphs, 29 adults and 186 indeterminate immature ticks (larvae or nymphs) were collected on 41 raptors (16 different species) in 17 distinct localities in the Brazilian territory. The following tick species were identified on wild raptors in the country: Amblyomma aureolatum (Pallas, 1772), Amblyomma auricularium (Conil, 1878), Amblyomma brasiliense Aragão, 1908, Amblyomma cajennense (Fabricius, 1787) sensu stricto, Amblyomma calcaratum Neumann, 1899, Amblyomma coelebs Neumann, 1899, Amblyomma dubitatum Neumann, 1899, Amblyomma longirostre (Koch, 1844), Amblyomma nodosum Neumann, 1899, Amblyomma ovale Koch, 1844, Amblyomma parkeri Fonseca & Aragão, 1952, Amblyomma sculptum Berlese, 1888, Haemaphysalis juxtakochi Cooley, 1946, Rhipicephalus microplus (Canestrini, 1888), and Rhipicephalus sanguineus (Latreille, 1806) sensu lato. This study is therefore a significant contribution to our knowledge of the ticks associated with Brazilian raptors.

Rhizoglyphus echinopus (Acari: Acaridae) associated with Atta sexdens (Insecta: Formicidae) / Rhizoglyphus echinopus (Acari: Acaridae) associado a Atta sexdens (Insecta: Formicidae)

Four deutonymphs of bulb mites (hypopus) from Rhizoglyphus echinopus (Fumouze & Robin) (Acari: Acaridae) were found attached to the head of Atta sexdens in Rio de Janeiro, Brazil. This mite species is commonly associated with ornamental plants and trees with bulbs, corms and tubers. The results of this study provided an insight into the phoretic relationship between mites and ants, indicating the role of the latter in the dispersion of the first. Despite the abundant and diverse mite fauna existing in ants, little is known about their diversity, biology, ecology and the nature of their associations.(AU)

Quatro deutoninfas de ácaros do bulbo (hipopus) da espécie Rhizoglyphus echinopus (Fumouze & Robin) (Acari: Acaridae) foram encontradas fixadas na cabeça de formigas da espécie Atta sexdens no Rio de Janeiro, Brasil. Essa espécie de ácaro está comumente associada a plantas ornamentais e plantas com bulbos e tubérculos. Os resultados desse estudo fornecem uma visão sobre a relação forética entre ácaros e formigas, indicando o papel destas últimas na dispersão dos primeiros. Apesar da abundância e da fauna diversa do ácaro em formigas, pouco se sabe sobre a diversidade, a biologia, a ecologia e a natureza dessa associação.(AU)

Human Parasitism by Amblyomma parkeri Ticks Infected with Candidatus Rickettsia paranaensis, Brazil.

Spotted fever is the main rickettsial disease in Brazil. We report 12 cases of human parasitism by Amblyomma parkeri in the Atlantic rainforest, an area of Brazil to which spotted fever is endemic. Nine of the ticks were infected with Candidatus Rickettsia paranaensis.

Two new species of the genus Geckobia Mégnin, 1878 (Acariformes, Prostigmata, Pterygosomatidae) from Peru.

Two new species of Geckobia Mégnin, 1878, Geckobia andina n. sp. and Geckobia circumdata n. sp., ectoparasites commonly reported on geckos, are described from the host species Phyllodactylus gerrhopygus (Wiegmann). The specimens were collected in the subtropical region of the Andean Pacific of Peru. The geographic distribution of species of Geckobia in South America and the Caribbean are mapped. Furthermore, a dichotomous key for the species of New World Geckobia is provided.