Genetic diversity, population structure and rickettsias in Amblyomma ovale in areas of epidemiological interest for spotted fever in Brazil.

Amblyomma ovale (Ixodida: Ixodidae) Koch, 1844 is widely-reported in the neotropical region and is the main vector in the epidemic cycle of Rickettsia parkeri strain Atlantic rainforest, a bioagent of a milder variety of spotted fever (SF). Because species with wide geographical distributions are known to exhibit variations that influence their vectorial capacity, the present study aimed to analyze genetic diversity and rickettsia infection of A. ovale collected during the investigation and surveillance of SF cases in the Cerrado and Atlantic rainforest (ARF) Brazilian biomes. Samples had their DNA extracted, amplified and sequenced for 16S rDNA, 12S rDNA, cytochrome oxidase subunit II and D-loop markers for tick analyses, as well as the gltA, htrA, ompA and ompB genes for rickettsia detection. Between 11 and 33 A. ovale haplotypes were identified, all of them exclusive to areas within individual analyzed biome areas. The A. ovale populations appeared to be structured, with Cluster I restricted to Cerrado + ARF isolated in Caatinga and Cluster II to ARF continuous area. Rickettsia bellii, R. parkeri strain Atlantic rainforest (first report for Goiás state, Cerrado), Rickettsia asemboensis (first record in A. ovale for Brazil) and Rickettsia felis (first detection in this ixodid) were identified. A. ovale clusters were not associated with rickettsia types.

Diversity of rickettsiae and potential vectors of spotted fever in an area of epidemiological interest in the Cerrado biome, midwestern Brazil.

The Brazilian state of Goiás, untouched by spotted fever (SF) until 2012, has subsequently reported cases of the disease in several regions. This study aimed to survey the diversity of potential vectors and rickettsia in areas of Goiás under environmental surveillance or case investigation for SF. Collected specimens were assayed with molecular biology technology using DNA extraction, amplification and sequencing of fragments of the genes gltA, ompA, ompB and sca4 to detect rickettsia in ticks and fleas. Amplification of cytochrome oxidase subunit II and 16S rRNA was performed to assist tick identification. Rickettsia felis (Rickettsiales: Rickettsiaceae) was found in Ctenocephalides felis (Bouché, 1835) (Siphonaptera: Pulicidae). Rickettsia bellii was found in Amblyomma rotundatum Koch, 1844 (Ixodida: Ixodidae) and in Amblyomma cajennense sensu lato. Rickettsia sp. strain NOD was found in Amblyomma nodosum Neumann, 1899. Of the Amblyomma cajennense complex, Amblyomma sculptum Berlese, 1888 was confirmed in the northern, northeast, midwest and southeast regions of Goiás, whereas Amblyomma cajennense sensu stricto (Fabricius, 1787) was found only in the northern region of the state. Amblyomma dubitatum Neumann, 1899 associated with a species of the A. cajennense complex was the most common epidemiological finding, although Rickettsia rickettsii was not detected. This is the first report of Rickettsia sp. strain NOD in Goiás.

Amblyomma sculptum: genetic diversity and rickettsias in the Brazilian Cerrado biome.

Amblyomma sculptum (Ixodida: Ixodidae) Berlese, 1888 is the most important tick vector in Brazil, transmitting the bioagent of the most severe form of spotted fever (SF) in part of the Cerrado (in the states of Minas Gerais and São Paulo). In another part of the Cerrado (Central-West region of Brazil), a milder form of SF has been recorded. However, neither the rickettsia nor the vector involved have been characterized. The aim of the current study was to analyse genetic variation and the presence of rickettsia in A. sculptum in Cerrado, from silent areas and with the milder form of SF. Samples were subjected to DNA extraction, amplification and sequencing of 12S rDNA, cytochrome oxidase subunit II and D-loop mitochondrial genes (for tick population analyses), and gltA, htrA, ompA and gene D (sca4) genes for rickettsia researches. Exclusive haplotypes with low frequencies, high haplotype diversity and low nucleotide diversity, star-shaped networks and significant results in neutrality tests indicate A. sculptum population expansions in some areas. Rickettsia amblyommatis, Candidatus Rickettsia andeanae and Rickettsia felis were detected. The A. sculptum diversity is not geographically, or biome delimited, pointing to a different potential in vector capacity, possibly associated with differing tick genetic profiles.

Predictive Factors for Fatal Tick-Borne Spotted Fever in Brazil.

In Brazil, two pathogenic Rickettsia species have been identified causing tick-borne spotted fever (SF). The aetiological agent Rickettsia rickettsii causes serious illness, particularly in the south-eastern region of the country. Moreover, the Rickettsia sp. strain Atlantic Rainforest cause milder clinical manifestations in south-eastern, south and north-east regions. This study has sought to analyse predictive factors for fatal SF. A case-control study was performed using disease notification records in Brazil. The cases included were individuals with laboratory confirmation and fatal progression of SF, while the controls included individuals with SF who were cured. A total of 386 cases and 415 controls were identified (1 : 1.1), and the cases and controls were similar in age. The factors identified as being protective against death were reported presence of ticks (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.41-0.88), residing in urban areas (OR, 0.47, 95% CI, 0.31-0.74) and presenting lymphadenopathy (OR, 0.43; 95% CI, 0.23-0.82). Males exhibited a greater chance of death (OR, 1.57; 95% CI, 1.13-2.18), as did patients who were hospitalized (OR, 10.82; 95% CI, 6.38-18.35) and who presented hypotension or shock (OR, 10.80; 95% CI, 7.33-15.93), seizures (OR, 11.24; 95% CI, 6.49-19.45) and coma (OR of 15.16; 95% CI, 8.51-27.02). The study demonstrates the severity profile of the SF cases, defined either as the frequency of hospitalization (even in cases that were cured) or as the increased frequency of the clinical complications typically found in critical patients. Opportune clinical diagnosis, a careful evaluation of the epidemiological aspects of the disease and adequate care for patients are determining factors for reducing SF fatality rates.

Analysis of Amblyomma sculptum haplotypes in an area endemic for Brazilian spotted fever.

Amblyomma sculptum (Ixodida: Ixodidae) Berlese, 1888, a member of the Amblyomma cajennense complex, is the major vector of Brazilian spotted fever (BSF) in southeastern Brazil. In this study, the genetic diversity of A. sculptum populations in the state of Rio de Janeiro (RJ), Brazil, was investigated because genetic variability in tick populations may be related to vector competence. Samples of A. sculptum from 19 municipalities in 7 regions of RJ were subjected to DNA extraction, amplification and sequencing of D-loop, cytochrome oxidase II and 12S rDNA mitochondrial genes. These sequences were used to map the genetic diversity of this tick. Amblyomma sculptum populations are genetically diverse in RJ, especially in the South Centre and Highland regions. Few unique haplotypes were observed in all populations, and the majority of genetic variation found was among ticks within each population. Phylogenetic reconstruction reinforced the assumption that all the haplotypes identified in RJ belong to A. sculptum. However, some RJ haplotypes are closer to A. sculptum from Argentina than to A. sculptum from elsewhere in Brazil. In RJ, A. sculptum has high genetic diversity, although little genetic differentiation. Observations also indicated a high level of gene flow among the studied populations and no evidence of population structure according to region in RJ.

Diversidade de ixodida em roedores e marsupiais capturados no Parque Estadual da Pedra Branca, Rio de Janeiro, Brasil / Diversity of ixodida in small rodents and marsupials in the Pedra Branca state park, state of Rio de Janeiro, Brazil

Durante 24 meses foram capturados, inspecionados e liberados no mesmo espaço do Parque Estadual da Pedra Branca, Rio de Janeiro, 96 marsupiais e 64 roedores. Neles foram recolhidos manualmente 105 carrapatos, de 10 espécies em duas famílias. A espécie de carrapato dominante entre os roedores foi Amblyomma longirostre e entre os marsupiais foi Ixodes loricatus. Houve correlação direta significativa entre a temperatura e a intensidade de parasitismo por carrapatos...

During 24 months 96 marsupials and 64 rodents were captured, inspected and set free in the same space of the Pedra Branca State Park, Rio de Janeiro. From them, 105 ticks from 10 species in two families were manually collected. The dominant tick species on the rodents was Amblyomma longirostre and on the marsupials was Ixodes loricatus. There was a significant correlation of the temperature in relation to intensity of parasitism for ticks, demonstrating that the higher the temperature, greater is the number of ticks...

Infestation by Pyemotes tritici (Acari, Pyemotidae) causes death of stingless bee colonies (Hymenoptera: Meliponina).

We report the infestation of stingless bee nests by the mite Pyemotes tritici, which killed four colonies of Tetragonisca angustula and one colony of Frieseomelitta varia in Brazil. The first infected colony, a colony of T. angustula, came from an area between Uberlândia and Araguari, Minas Gerais. The transfer of the mites to the other colonies occurred through the transfer of infected combs and subsequent manipulations. Other colonies in the same meliponary, which had not been manipulated, were not infected. The infestation was terminated by isolating the dead colonies from the meliponary.

Carrapatos em aves selvagens no Zoológico de Sorocaba - São Paulo, Brasil / Ticks em wild fowls at Sorocaba - São Paulo State, Brazil

Eight wild fowls kept in captivity at a Brazilian Zoo were examined from july 1994 to October 2000. One hundred twenty-three Ixodidae specimens were collected and sent to the Ixodides Laboratory at the Instituto Oswaldo Cruz, Rio de Janeiro, Brazil. They were examined by stereomicroscopy and were identified as Amblyomma longirostre (53), A. pacae (50), A. cajennense (14), and A. parvum (6).

Inespecificidade parasitária em Argas (Persicargas) miniatus Koch, 1844 (Acari: Argasidae) / Nonspecificity of parasitism on Argas (Persicargas) miniatus Koch, 1844 (Acari: Argasidae)

Foram coletados 665 espécimes de Argas miniatus em dois municípios dos estados da Bahia e Minas Gerais. Destes, 596 (89,6 por cento) tinham se alimentado, sendo que 489 (82 por cento) reagiram para um único tipo de sangue, distribuídos entre aves (46,8 por cento), roedores (30,9 por cento), gambás (14,5 por cento), bovinos (4,3 por cento) e eqüinos (3,5 por cento). Nesse tipo de reação, o sangue de mamíferos foi detectado em 53,2 por cento (260/489) dos argasídios. As reações múltiplas foram observadas em 107 (17,9 por cento) carrapatos, com sangue de aves presente em 84,1 por cento (90/107), enquanto, o sangue de mamíferos reagiu em 100 por cento (107/107). Os resultados apontam para a inespecificidade parasitária

Six hundred and sixty-five specimens of Argas miniatus were collected in two municipalities of Bahia and Minas Gerais states, Brazil. Five hundred and ninety-six (89.6 percent) of them had fed and 489 (82 percent) of them reacted to only one type of blood, including birds (46.8 percent), rodents (30.9 percent), opossuns (14.5 percent), bovines (4.3 percent) and horses (3.5 percent). In that reaction, the type of mammal blood was detected in 53.2 percent (260/489) of the ticks. Multiple reactions were observed in 107 (17.9 percent) ticks, with blood of birds present in 84.1 percent (90/107), while the blood of mammals was detected in 100 percent (107/107). The results point for the nonspecificity of parasitism

Equine Monocytic Ehrlichiosis (EME) in Rio de Janeiro State, Brazil / Ehrliquiose Monocítica Eqüina (EME) no estado do Rio de Janeiro, Brasil

Realizaram-se testes de imunofluorescência indireta (IFI) para Ehrliquiose Monocítica Eqüina (EME) em soros de 27 eqüinos, provenientes de duas propriedades do estado do Rio de Janeiro (regiões Metropolitana e Serrana) onde ocorreram manifestações clínicas sugestivas de EME. Coletaram-se duas amostras de sangue de cada animal. Os intervalos entre as coletas variaram entre 30 e 180 dias. Vinte e um animais (77,8 por cento) foram reagentes à IFI com título 1:50, nos testes realizados nas duas amostras coletadas. Os demais (22,2 por cento) - animais 1 a 6 - foram reagentes à IFI, com títulos sorológicos de 1:100, 1:200, 1:400, 1:400, 1:400 e 1:800 na primeira coleta e 1:200, 1:800, 1:200, 1:400, 1:800 e 1:800 na segunda coleta, respectivamente. Três animais (1, 4 e 5) apresentaram manifestações subclínicas. Um animal (2) recuperou-se após o tratamento. Dois animais (3 e 6) evoluíram para óbito. Títulos sorológicos maiores que 1:320 são conclusivos para o diagnóstico específico. Este é o primeiro relato de EME no estado do Rio de Janeiro, Brasil

Número de cerdas internas do órgão de Haller em larvas de Amblyoma cajennense (Fabricius, 1787) (Acari: Ixodidae) nos municípios de Silva Jardim e Itaguaí, RJ / Internal setae number of the larvae Haller’s organ of Amblyoma cajennense (Fabricius, 1787) (Acari: Ixodidae) from Silva Jardim and Itaguaí, RJ

Larvae of Amblyomma cajennense (Fabricius, 1787), were obtained under laboratory conditions. The larvae were killed in hot water, preserved in 70° ethanol and prepared in definitive whole mounts. Two hundred larvae were examined under brightjield microscopy with an immersion objective in order to analyze the variation of the number of internal setae of the right and left side of the Haller's organ chamber with the purpose of utilize them as chaetotaxy parameter for specific diagnosis.

Ocorrência de Babesia sp em pequenos roedores no Brasil / Occurrence of Babesia sp in small rodents in Brazil

Foi analisada a ocorrência de babesiose em pequenos roedores nos municípios de Silva Jardim e Nova lguaçu, Estado do Rio de Janeiro. Foram capturados 44 roedores de seis espécies diferentes e entre eles a prevalência da infecção foi de 27,3 por cento. Rattus norvegicus foi considerado o principal reservatório (50,0 por cento) e Oligoryzomys nigripes como novo hospedeiro para Babesia sp. Este foi o primeiro relato de Babesia sp. em roedores no Brasil. A freqüência de roedores positivos e o risco de infecção dos roedores não diferiram entre as áreas estudadas.

Evaluation of the acarofauna of the domiciliary ecosystem in Juiz de Fora, State of Minas Gerais, Brazil.

From August 1999 to January 2000, samples of house dust were collected from 160 domiciles in the city of Juiz de Fora, State of Minas Gerais, Brazil. In 36 of these domiciles kitchen samples were obtained. Prevalence rate was 77.5%, varying according to the geographical sector. There were found 2,278 specimens of mites, with 1,530 (67.2%) in the adult stage and 748 (32.8%) in immature forms. The main species found were Dermatophagoides pteronyssinus, D. farinae, Euroglyphus maynei, Blomia tropicalis and Tyrophagus putrescentiae. In a minor incidence we found Lepidoglyphus destructor, Suidasia pontificiae, Chortoglyphus arcuatus, Cheyletus malaccensis, C. fortis, Ker bakeri, Cheletonella vespertilionis, C. caucasica and others. C. vespertilionis and C. caucasica were identified for the first time in the domiciliary ecosystem and in Brazil. The abundance rate and the infestation intensity were analyzed. There was a varied correlation between climatic conditions and positive domiciles and number of mites. The difference between the number of positive domiciles in the urban area and in the expanding urban area was significant and so was the difference between samples from the domiciles compared to those from the kitchens.

Seasonal analysis of the number of aeropiles in Anocentor nitens (Neumann, 1897) (Acari: Ixodidae) from the State of Rio de Janeiro, Brazil.

Variation between aeropile numbers of the right and left peritrematic plate in male and female Anocentor nitens (Neumann, 1897) is reported from a site in Brazil. From January to December 1998, 146 males and 247 females of A. nitens were recovered from Equus caballus L. in Silva Jardim District, State of Rio de Janeiro. Asymmetry of numbers of aeropiles between right and left plates occurred in 83.6% of the males and 82.2% of the females. Differences in the number of aeropiles between the sexes were not significant. Quantitative variation of aeropiles was correlated to the period of recovery, with significant asymmetry detected in August-September and November-December, mainly in males. Results suggest an adaptation, especially in the male ticks, that expresses itself as greater variation in the number of aeropiles in some periods of the year.

Cebus apella (Primata: Cebidae) as a new host for Fonsecalges johnjadini (Acari: Psoroptidae, Cebalginae) with a description of anatomopathological aspects.

Mites collected from the auditory canal of Cebus apella (capuchin monkey), family Cebidae, were identified as Fonsecalges johnjadini (Psoroptidae, Cebalginae). It is the first record of this parasite from this monkey. This paper emphasizes the importance of clinical and anatomopathological examinations for parasitic diagnosis in wild animals.

Epidemiological aspects of the Brazilian spotted fever: seasonal activity of ticks collected in an endemic area in São Paulo, Brazil

Carrapatos de vegetação e de animais foram coletados mensalmente durante o período de um ano (1993-1994) em uma área endêmica de febre maculosa brasileira no município de Pedreira, São Paulo. Seis espécies de carrapatos foram identificadas Amblyomma cajennense, Amblyomma cooperi, Amblyomma triste, Anocentor nitens, Rhipicephalus sanguineus e Boophilus microplus. Somente a primeira espécie foi suficientemente abundante para permitir um estudo quantitativo com atividade sazonal, embora a distribuição e fonte de captura de outras espécies fossem observadas e aqui relatadas. Estas informações são correlacionadas com a epidemiologia da rickettsiose transmitida por carrapato.

Ticks were collected from vegetation and animals at monthly intervals during one year (1993-1994) in an endemic area of Brazilian spotted fever in the Country of Pedreira, State of São Paulo. Six species of ticks were identified Amblyomma cajennense, Amblyomma cooperi, Amblyomma triste, Anocentor nitens, Rhipicephalus sanguineus and Boophilus microplus. Only the first species was sufficiently numerous to permit a quantitative study with seasonal activity, although the distribution and source of capture of other species were observed and are reported. This information is correlated with the epidemiology of tick-borne rickettsiosis.

Epidemiological aspects of the Brazilian spotted fever: seasonal activity of ticks collected in an endemic area in São Paulo, Brazil.

Ticks were collected from vegetation and animals at monthly intervals during one year (1993-1994) in an endemic area of Brazilian spotted fever in the Country of Pedreira, State of São Paulo. Six species of ticks were identified Amblyomma cajennense, Amblyomma cooperi, Amblyomma triste, Anocentor nitens, Rhipicephalus sanguineus and Boophilus microplus. Only the first species was sufficiently numerous to permit a quantitative study with seasonal activity, although the distribution and source of capture of other species were observed and are reported. This information is correlated with the epidemiology of tick-borne rickettsiosis.

Reavaliaçäo dos caracteres da placa peritremática para diagnose de Anocentor nitens (Neumann, 1897), na Regiäo Sudeste / Evaluation of the characteristics of peritremal plate for Anocentor nitens (Neumann, 1897) diagnosis in the Southern Region of Brazil

Duzentos e quatro fêmeas e cento e vinte machos de Anocentor nitens (Neumann, 1897), oriundos de eqüídeos manejados em 12 municípios da Regiäo Sudeste do Brasil, foram analisados morfologicamente quanto aos caracteres da placa peritremática, parâmetro taxonômico utilizados na diagnose desta espécie. As variaçöes ocorridas no número de aerópilos da placa peritremática de machos e fêmeas de A. nitens apresentaram curvas de distribuiçäo normal para a regiäo e sugerem a formaçäo de "cline" a partir do Estado de Minas Gerais em direçäo aos Estados do Rio de Janeiro e de Säo Paulo