Tick-Derived Peptide Blocks Potassium Channel TREK-1.

Ticks transmit a variety of pathogens, including rickettsia and viruses, when they feed on blood, afflicting humans and other animals. Bioactive components acting on inflammation, coagulation, and the immune system were reported to facilitate ticks' ability to suck blood and transmit tick-borne diseases. In this study, a novel peptide, IstTx, from an Ixodes scapularis cDNA library was analyzed. The peptide IstTx, obtained by recombinant expression and purification, selectively inhibited a potassium channel, TREK-1, in a dose-dependent manner, with an IC50 of 23.46 ± 0.22 µM. The peptide IstTx exhibited different characteristics from fluoxetine, and the possible interaction of the peptide IstTx binding to the channel was explored by molecular docking. Notably, extracellular acidification raised its inhibitory efficacy on the TREK-1 channel. Our results found that the tick-derived peptide IstTx blocked the TREK-1 channel and provided a novel tool acting on the potassium channel.

Occurrence of Coxiella burnetii in wild lagomorphs and their ticks in Spanish Mediterranean ecosystems.

BACKGROUND: Coxiella burnetii, the causative agent of Q fever, is a zoonotic multi-host vector-borne pathogen of major public health importance. Although the European Food Safety Authority has recently made the monitoring of this bacterium in wildlife a priority, the role of wild lagomorphs in the transmission and maintenance of C. burnetii is poorly understood. AIMS: The aims of this study were to determine the prevalence and risk factors associated with C. burnetii circulation in European wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis) and to assess the presence of this pathogen in ticks that feed on them in Mediterranean ecosystems in Spain, the country with the highest number of reported cases of Q fever in Europe. METHODS: A total of 574 spleen samples were collected from 453 wild rabbits and 121 Iberian hares, and 513 ticks (processed in 120 pools) between the 2017/2018 and 2021/2022 hunting seasons. RESULTS: C. burnetii DNA was detected in 103 (17.9%; 95% CI: 14.8-21.1) of the 574 wild lagomorphs tested. By species, prevalence was 16.3% (74/453; 95% CI: 12.9-19.7) in the European wild rabbit and 24.0% (29/121; 95% CI: 16.4-31.6) in the Iberian hare. At least one positive lagomorph was found on 47.9% of the 96 hunting estates sampled and in every hunting season since 2018/2019. Two risk factors associated with C. burnetii infection were as follows: outbreak of myxomatosis on the hunting estate in the month prior to sampling and high tick abundance observed by gamekeepers on the hunting estate. C. burnetii DNA was also found in 33 of the 120 (27.5%; 95% CI: 19.5-35.5) tick pools tested. The pathogen was detected in 66.7% (4/6), 29.2% (26/89) and 21.4% (3/14) of Haemaphysalis hispanica, Rhipicephalus pusillus and Hyalomma lusitanicum pools respectively. CONCLUSIONS: This study provides new epidemiological data on C. burnetii in European wild rabbits and is the first survey on this zoonotic pathogen performed in Iberian hares. Our results indicate widespread endemic circulation of C. burnetii and highlight the importance of both wild lagomorph species as natural reservoirs of this zoonotic bacterium in Mediterranean ecosystems in southern Spain, which may be of public and animal health concern. The high prevalence and wide diversity of positive tick species suggest the possible role of ticks in the epidemiological cycle of C. burnetii, with the potential risk of transmission to sympatric species, including humans.

New insights into the molecular phylogeny, biogeographical history, and diversification of Amblyomma ticks (Acari: Ixodidae) based on mitogenomes and nuclear sequences.

BACKGROUND: Amblyomma is the third most diversified genus of Ixodidae that is distributed across the Indomalayan, Afrotropical, Australasian (IAA), Nearctic and Neotropical biogeographic ecoregions, reaching in the Neotropic its highest diversity. There have been hints in previously published phylogenetic trees from mitochondrial genome, nuclear rRNA, from combinations of both and morphology that the Australasian Amblyomma or the Australasian Amblyomma plus the Amblyomma species from the southern cone of South America, might be sister-group to the Amblyomma of the rest of the world. However, a stable phylogenetic framework of Amblyomma for a better understanding of the biogeographic patterns underpinning its diversification is lacking. METHODS: We used genomic techniques to sequence complete and nearly complete mitochondrial genomes -ca. 15 kbp- as well as the nuclear ribosomal cluster -ca. 8 kbp- for 17 Amblyomma ticks in order to study the phylogeny and biogeographic pattern of the genus Amblyomma, with particular emphasis on the Neotropical region. The new genomic information generated here together with genomic information available on 43 ticks (22 other Amblyomma species and 21 other hard ticks-as outgroup-) were used to perform probabilistic methods of phylogenetic and biogeographic inferences and time-tree estimation using biogeographic dates. RESULTS: In the present paper, we present the strongest evidence yet that Australasian Amblyomma may indeed be the sister-group to the Amblyomma of the rest of the world (species that occur mainly in the Neotropical and Afrotropical zoogeographic regions). Our results showed that all Amblyomma subgenera (Cernyomma, Anastosiella, Xiphiastor, Adenopleura, Aponomma and Dermiomma) are not monophyletic, except for Walkeriana and Amblyomma. Likewise, our best biogeographic scenario supports the origin of Amblyomma and its posterior diversification in the southern hemisphere at 47.8 and 36.8 Mya, respectively. This diversification could be associated with the end of the connection of Australasia and Neotropical ecoregions by the Antarctic land bridge. Also, the biogeographic analyses let us see the colonization patterns of some neotropical Amblyomma species to the Nearctic. CONCLUSIONS: We found strong evidence that the main theater of diversification of Amblyomma was the southern hemisphere, potentially driven by the Antarctic Bridge's intermittent connection in the late Eocene. In addition, the subgeneric classification of Amblyomma lacks evolutionary support. Future studies using denser taxonomic sampling may lead to new findings on the phylogenetic relationships and biogeographic history of Amblyomma genus.

The Vector Competence of Asian Longhorned Ticks in Langat Virus Transmission.

Haemaphysalis longicornis (the longhorned tick), the predominant tick species in China, serves as a vector for a variety of pathogens, and is capable of transmitting the tick-borne encephalitis virus (TBEV), the causative agent of tick-borne encephalitis. However, it is unclear how these ticks transmit TBEV. Langat virus (LGTV), which has a reduced pathogenicity in humans, has been used as a surrogate for TBEV. In this study, we aimed to investigate the vector competence of H. longicornis to transmit LGTV and demonstrate the efficient acquisition and transmission of LGTV between this tick species and mice. LGTV localization was detected in several tick tissues, such as the midgut, salivary glands, and synganglion, using quantitative PCR and immunohistochemical staining with a polyclonal antibody targeting the LGTV envelope protein. We demonstrated the horizontal transmission of LGTV to different developmental stages within the same generation but did not see evidence of vertical transmission. It was interesting to note that we observed mice acting as a bridge, facilitating the transmission of LGTV to neighboring naïve ticks during blood feeding. In conclusion, the virus-vector-host model employed in this study provides valuable insights into the replication and transmission of LGTV throughout its life cycle.

Aural hematoma in lambs associated with Otobius megnini (Ixodida: Argasidae) infestation.

In this report we described a case of aural hematomas in three lambs associated with Otobius megnini (Ixodida: Argasidae) infestation. From April to May 2021, five 3-month-old Hampshire cross lambs presented with unilateral aural hematomas. Upon otoscopic examination, engorged soft ticks (O. megnini) were observed in the external ear canals of three of the five lambs. The remaining two lambs had lesions consistent with infestation and were in a shared environment and deemed likely to have been infected. The treatment of all animals was based on the drainage of the serosanguinous fluid through an incision in the internal space of the ear pinna. Upon physical inspection of the entire flock (n = 310), O. megnini infestation was observed in one additional animal that did not have a hematoma. Following animal and environmental ectoparasiticide treatment with permethrin, no recurrences or additional cases of aural hematomas were observed in the flock in the following two-year period. To the authors' knowledge, this is the first description of aural hematomas in lambs associated with O. megnini infestation with successful recovery after surgery and off-label acaricide treatment.

The diverse functions of Mu-class Glutathione S-transferase HrGSTm1 during the development of Hyalomma rufipes with a focus on the detoxification metabolism of cyhalothrin.

BACKGROUND: Glutathione S-transferases (GSTs) are a superfamily of multifunctional enzymes in living organisms with metabolic and detoxification functions, which can detoxify exogenous and endogenous compounds and thereby reduce the damage caused by toxic substances to the body. Ticks are obligate blood-sucking ectoparasites that can transmit various pathogens, and the characterization of tick-derived GSTs may help improve current understanding of the molecular mechanism of tick resistance to insecticides. In this study, a novel GST gene, named HrGSTm1, was identified from Hyalomma rufipes. METHODS: Sequence analysis was performed by using bioinformatics techniques. A prokaryotic expression system was used to obtain the recombinant expression protein rHrGSTm1. Detection of spatiotemporal expression patterns of target genes and their response to the toxicity of cyhalothrin on female H. rufipes was performed by using a quantitative PCR platform. The optimal enzymological parameters of rHrGSTm1 using glutathione as substrate were calculated. The antioxidant capacity of the recombinant protein was evaluated by DPPH• (1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl). Knockdown of the HrGSTm1 genes through RNA interference was used to analyze their effects on the physiological parameters of ticks. The changes in HrGSTm1 messenger RNA expression patterns under cypermethrin stress were analyzed. RESULTS: The complementary DNA sequence of HrGSTm1 contained a 672-bp open reading frame, which potentially encoded 223 amino acids. The predicted molecular weight was 25.62 kDa, and the isoelectric point 8.22. HrGSTm1 is a Mu-class GST, belonging to the cytoplasmic GSTs with no signal peptide observed. The Vmax and Km of rHrGSTm1 were 3.367 ± 0.81 uM and 2.208 ± 0.76 uM, respectively, and its activities were dependent on different temperatures and pH conditions; the scavenging rate of rHrGSTm1 to DPPH• reached 76.4% at 1.25 mg/ml. Variable expressions of HrGSTm1 were observed under various treatment periods and in different tissues, with the highest appearing in eggs (analysis of variance [ANOVA], F(2, 9) = 279.9, P < 0.0001) and Malpighian tubules (ANOVA, F(3, 12) = 290.5, P < 0.0001). After knockdown of HrGSTm1, compared with the control group, the mortality in the treatment group was increased by 16.7%, the average oviposition rate decreased by 33.9%, the average engorged body weight decreased by 287.38 mg and egg weight decreased by 127.46 mg, although only the engorged body weight was significantly different (t-test, t(44) = 2.886, P = 0.006). After exposure to three sublethal concentrations (LC05, LC10, LC50) of cyhalothrin, the expression level of HrGSTm1 in the midgut, ovary and salivary gland was upregulated, whereas in Malpighian tubules, it showed a trend of upregulation at first and then downregulation, implying different functions during the detoxification in different tissues. CONCLUSIONS: In this study, a novel GST of the Mu-class was successfully isolated from H. rufipes and systematically subjected to bioinformatic analysis and recombination identification. The variation trend of HrGSTm1 expression level in different tissues suggests that the gene has different detoxification functions in different tissues. The potential function of this gene was analyzed to provide basic research for further investigation of its detoxification mechanism.

Studies on the Determination of Ectoparasites and the Prevalence Rate in Cattle in Izmir, Aydin and Mugla Regions.

Objective: The aim of the study is to determine the prevalence rates of ectoparasites (external parasites) seen in cattle in Mugla, Aydin and Izmir regions. Methods: For ectoparasite screening, a total of 1,353 cattle breeds from Mugla, Aydin and Izmir regions were included in the study. Ectoparasite samples were collected with the help of hand, forceps, comb and scalpel, brought to the laboratory in plastic containers containing 70% alcohol and examined under a microscope. Results: In the study, 191 (14.12%) of 1,353 cattle were infested with external parasites. Of the cattle, 138 (72.25%) ticks, 24 (12.57%) lice, 9 (4.71%) tabanid, 8 (4.19%) hippoboscid, 7 (3.66%) fleas and 5 (2.62%) mites were detected. Accordingly, 4 tick species in cattle Hyalomma marginatum, Hyalomma excavatum, Hyalomma detritum, Rhipicephalus turanicus, 4 lice species (Bovicola bovis, Linognathus vituli, Solenopotes capillatus, Haematopinus quadripertusus ), 1 mite species (Chorioptes bovis), 2 flea species (Ctenocephalides canis, Ctenocephalides felis), 1 hippoboscid fly species (Hippobosca equina) ve 3 tabanid fly species (Tabanus bromius, Tabanus exclusus, Philipomyia aprica) diagnosed. Conclusion: The presence of external parasites varied depending on the frequency of antiparasitic use in cattle.

Tick innate immune responses to hematophagy and Ehrlichia infection at single-cell resolution.

Introduction: Ticks rely on robust cellular and humoral responses to control microbial infection. However, several aspects of the tick's innate immune system remain uncharacterized, most notably that of the immune cells (called hemocytes), which are known to play a significant role in cellular and humoral responses. Despite the importance of hemocytes in regulating microbial infection, our understanding of their basic biology and molecular mechanisms remains limited. Therefore, we believe that a more detailed understanding of the role of hemocytes in the interactions between ticks and tick-borne microbes is crucial to illuminating their function in vector competence and to help identify novel targets for developing new strategies to block tick-borne pathogen transmission. Methods: This study examined hemocytes from the lone star tick (Amblyomma americanum) at the transcriptomic level using the 10X genomics single-cell RNA sequencing platform to analyze hemocyte populations from unfed, partially blood-fed, and Ehrlichia chaffeensis-infected ticks. The functional role of differentially expressed hemocyte markers in hemocyte proliferation and Ehrlichia dissemination was determined using an RNA interference approach. Results and discussion: Our data exhibit the identification of fourteen distinct hemocyte populations. Our results uncover seven distinct lineages present in uninfected and Ehrlichia-infected hemocyte clusters. The functional characterization of hemocytin, cystatin, fibronectin, and lipocalin demonstrate their role in hemocyte population changes, proliferation, and Ehrlichia dissemination. Conclusion: Our results uncover the tick immune responses to Ehrlichia infection and hematophagy at a single-cell resolution. This work opens a new field of tick innate immunobiology to understand the role of hemocytes, particularly in response to prolonged blood-feeding (hematophagy), and tick-microbial interactions.

Ectoparasitic mites, ticks (Acari: Trombidiformes, Mesostigmata, Ixodida) and insects (Insecta: Psocodea, Siphonaptera) of ground-dwelling small mammals in the Baltic States. An annotated checklist.

This paper presents an annotated checklist of 77 species of ectoparasitic mites, ticks (Acari: Trombidiformes, Mesostigmata, Ixodida) and insects (Insecta: Psocodea, Siphonaptera) found on ground-dwelling small mammals in the Baltic States (Estonia, Latvia, Lithuania). Eight species of five genera of chigger mites (Trombidiformes: Trombiculidae), 26 species of eight genera of laelapid mites (Mesostigmata: Laelapidae), six species of two genera of ixodid ticks (Ixodida: Ixodidae), 11 species of three genera of blood-sucking lice (Psocodea: Hoplopleuridae, Pediculidae, Polyplacidae) and 26 species of 15 genera of fleas (Siphonaptera: Ceratophyllidae, Ctenophthalmidae, Hystrichopsyllidae, Pulicidae) were recorded on ground-dwelling small mammals in the Baltic States. Neotrombicula japonica (Tanaka, Kaiwa, Teramura & Kagaya), Neotrombicula vulgaris (Schluger), Miyatrombicula muris (Oudemans), Hoplopleura edentula Fahrenholz and Polyplax hannswrangeli Eichler are recorded for the first time in the Baltic States.

Febre maculosa brasileira na cidade de Jacareí, Vale do Paraíba, SP: descrição dos componentes da paisagem / Brazilian Spotted Fever in the city of Jacareí, Vale do Paraíba region, São Paulo State: description of landscape components

A Febre Maculosa Brasileira (FMB) é uma zoonose infecciosa, febril, aguda e exantemática, de notificação compulsória no Brasil, que tem como agente patogênico bactérias da espécie Rickettsia rickettsii, que são transmitidas por alguns carrapatos do gênero Amblyomma. No Brasil, a maior incidência de casos ocorre no Estado de São Paulo, onde há casos em locais de grande urbanização, e apresenta alta taxa de letalidade que pode variar de 30% à 60% dependendo da região do Estado. A cidade de Jacareí está na região do Vale do Paraíba, onde alguns municípios identificaram em seus territórios casos humanos da doença. No período de 2014 a 2020 ocorreram quatro casos confirmados de FMB com Local Provável de Infecção (LPI) no município de Jacareí, SP, com taxa de letalidade de 100 %. O estudo tem como objetivo descrever a ocorrência de Febre Maculosa Brasileira no Município de Jacareí nesse período. Para essa finalidade, foram selecionadas cinco áreas para esse estudo epidemiológico com propósito descritivo, retrospectivo, e com abordagem ecológica. O estudo foi baseado na revisão dos relatórios de investigações epidemiológicas do banco de dados da Diretoria de Vigilância em Saúde do Município de Jacareí. Os casos humanos descritos tem predomínio de indivíduos do sexo masculino na faixa etária de 50 a 69 anos associados a atividades recreativas e ocupacionais praticadas em áreas urbanas ou periurbanas de mata ciliar ou próximo a estas. As caracteristicas do perfil paisagístico comuns para as áreas estudadas foram determinados por: cobertura vegetal nativa e espelho d'água com alta fragmentação, locais de ocupação e deslocamento humano presentes em 30,4% da área considerada em média, presença de hospedeiros primários, presença de animais sentinela sororreagentes e relato de parasitismo humano. As notificações de parasitismo humano devem ser implementadas no município para uma posterior pesquisa em campo e mapeamento de novos locais possivelmente infestados, e a sinalização com placas informativas das áreas infestadas deve ser mantida e constantemente atualizada. A realização de atividades educativas deve estar voltada para perfil epidemiológico dos indivíduos considerados vulneráveis, e aos profissionais de saúde informando sobre ambientes predispostos para ocorrência da FMB.

Brazilian Spotted Fever (BSF) is an infectious, febrile, acute and exanthematic zoonosis, of compulsory notification in Brazil, which has Rickettsia rickettsii bacterium as its pathogenic agent, which are transmitted by some ticks species of the genus Amblyomma. In Brazil the highest incidence of cases occurs in the State of São Paulo where there are cases in places of great urbanization, and it has a high lethality rate that can vary from 30 % to 60 % depending on the region of the State. The city of Jacareí is located in the Vale do Paraiba region, São Paulo, Brazil. In this region some municipalities have identified human cases of the disease within their territories. In the period between 2014 and 2020 there were four human cases of the disease that had its Probably Local of Infection in the municipality of Jacareí, with a lethality rate of 100%. We aim to describe the occurrence of BSF in the Jacareí municipality in that timeframe. For this goal, five areas were selected for this epidemiological study, with a descriptive, retrospective purpose, and with an ecological approach. The study was based on a review of epidemiological investigation reports from the Jacareí Health Surveillance Directorate database. The described human cases predominantly affect males in the age range of 50 to 69 years, associated with recreational and occupational activities carried out in urban or peri-urban areas near riparian forests. The common landscape characteristics found in the studied areas were determined as follows: native vegetation cover and water mirrors with high fragmentation, human occupation and mobility present in 30.4% of the considered area on average, presence of primary hosts, presence of seropositive sentinel animals, and reports of human parasitism. Notifications of human parasitism should be implemented in the municipality for subsequent field research and mapping of potentially infested areas. Signage with informative plaques in infested areas should be maintained and regularly updated. Educational activities should focus on the epidemiological profile of vulnerable individuals and inform healthcare professionals about environments predisposed to Brazilian Spotted Fever occurence.

Prevalence and diversity of ectoparasites in Wild Rock Pigeon (Columba livia) in Punjab region, Pakistan / Prevalência e diversidade de ectoparasitas em Wild Rock Pigeon (Columba livia) na região de Punjab, Paquistão

The current study was carried out to estimate the prevalence and diversity of ectoparasites in rock pigeons in different regions of Punjab, Pakistan. A total of 120 birds were captured from March 2017 to February 2019. The ectoparasites were collected by standard procedures and preserved in 70% ethanol containing one drop of glycerin. Data related to age, health status, sex, type of area, sampling location and season were collected using a standardized form. Ectoparasites were identified based on morphological characteristics by using identification keys. Ninety-six (80%) birds were infested with ectoparasites. A total of seven families and thirteen species of different ectoparasites were observed. Mainly, seven species of lice, two species of flies, one species of tick and three species of mites were recovered from infested birds. The female pigeons were more often infested (89.02%) than male pigeons (60.52%). The prevalence was found higher during summer (100%) as compared to other seasons. The infestation rate was higher in Industrial area (97.50%) as compared to other regions. The highest prevalence of ectoparasites (100%) was recorded from Sargodha district. There was significant (P < 0.05) variation among number of ectoparasites on wing, chest, tail and neck within age groups, seasons and ecological zones. The occurrence of parasites in relation to area, age, health status, sex and season were significant. The infestation rate of parasites in rock pigeon is high in different districts of Punjab. It is recommended that these wild birds infested with multiple species of ectoparasites could be the potential source of infestations in domesticated birds if they come in contact with them. The contact of domesticated birds should be prevented from wild birds to minimize the chance of cross species transmission of ectoparasites.

O presente estudo foi realizado para estimar a prevalência e diversidade de ectoparasitas em pombos-das-rochas em diferentes regiões de Punjab, Paquistão. Um total de 120 aves foram capturadas de março de 2017 a fevereiro de 2019. Os ectoparasitas foram coletados por procedimentos padrão e preservados em etanol 70% contendo uma gota de glicerina. Os dados relativos à idade, estado de saúde, sexo, tipo de área, local de amostragem e época do ano foram coletados em formulário padronizado. Os ectoparasitas foram identificados com base nas características morfológicas por meio de chaves de identificação. Noventa e seis (80%) aves estavam infestadas com ectoparasitas. Um total de sete famílias e treze espécies de diferentes ectoparasitas foram observados. Principalmente, sete espécies de piolhos, duas espécies de moscas, uma espécie de carrapato e três espécies de ácaros foram recuperadas de aves infestadas. Os pombos fêmeas foram infestados mais frequentemente (89,02%) do que os pombos machos (60,52%). A prevalência encontrada foi maior no verão (100%) em comparação com as outras estações. A taxa de infestação foi maior na área Industrial (97,50%) em relação às demais regiões. A maior prevalência de ectoparasitas (100%) foi registrada no distrito de Sargodha. Houve variação significativa (P <0,05) entre o número de ectoparasitas na asa, tórax, cauda e pescoço dentro das faixas etárias, estações do ano e zonas ecológicas. A ocorrência de parasitas em relação à área, idade, estado de saúde, sexo e estação do ano foi significativa. A taxa de infestação de parasitas em pombo-correio é alta em diferentes distritos de Punjab. Recomenda-se que essas aves selvagens infestadas com várias espécies de ectoparasitas possam ser a fonte potencial de infestações em aves domesticadas se entrarem em contato com elas. O contato de aves domesticadas deve ser evitado com aves selvagens para minimizar a chance de transmissão cruzada de ectoparasitas.

Potential of Tetradenia riparia leaf essential oil and its fractions in controlling Aedes aegypti and Rhipicephalus microplus larvae

Tetradenia riparia (Hochst.) Codd (Lamiaceae) is a shrub, commonly known as ginger bush or false myrrh, and several studies have shown that T. riparia exhibits a variety of biological properties. This study aimed to determine the chemical composition of T. riparia essential oil and its fractions, investigate their anticholinesterase activity, and assess their larvicidal activity against the cattle tick Rhipicephalus microplus and the mosquito Aedes aegypti. Eleven essential oil fractions were obtained by fractionation and analyzed by gas chromatography/mass spectrometry. Larvicidal activity against R. microplus and third-instar A. aegypti was assessed using a larval packet test and a larval immersion test, respectively. Anticholinesterase activity was determined by a bioautographic method. Forty-nine compounds were identified in the essential oil, of which the major classes were oxygenated sesquiterpenes (45.95%) and sesquiterpene hydrocarbons (35.20%) and the major components were isospathulenol (17.40%), ß-caryophyllene (15.61%), 14-hydroxy-9-epi-caryophyllene (10.07%), 14-hydroxy-α-muurolene (8.32%), and 9ß,13ß-epoxy-7-abietene (5.53%). Bioassays showed that T. riparia essential oil (LC50 = 1.56 µg/mL) and FR3 (LC50 = 0.30 µg/mL) were the most active against R. microplus and A. aegypti larvae, respectively. The essential oil and FR1, FR2, and FR3 exhibited acetylcholinesterase inhibitory activity. These results indicate that T. riparia essential oil and its fractions hold promise in the development of novel, environmentally safe agents for the control of R. microplus and A. aegypti larvae.

Conocimiento de los costarricenses sobre parasitosis en la población infantil / Knowledge of Costa Ricans about parasitosis in children population / Conhecimento dos costarriquenhos sobre parasitoses na população infantil

Objetivo: los parásitos son organismos que viven en el interior o sobre otra especie para su propio beneficio. Logran afectar plantas, animales y humanos. Los niños son más vulnerables a infectarse, pero la incidencia ha disminuido en Costa Rica gracias a la mejora en salubridad. El objetivo de este estudio fue evaluar el conocimiento general que tiene la población costarricense con respecto a las parasitosis infantiles. Metodología: se realizó un estudio observacional, descriptivo de tipo transversal, a una muestra de 196 sujetos. Se presentó encuesta a costarricenses mayores de 18 años que tuvieran un dispositivo con acceso a internet. Se consultó sobre el conocimiento del cuadro clínico de las parasitosis infantiles en Costa Rica. Resultados: la mayoría de los participantes eran universitarios (68.3%). El 89.9% cree que los parásitos de las mascotas pueden infectar a los humanos. Los parásitos más conocidos fueron los piojos 173 (88.3%). La parte del cuerpo que se considera más afectada por los parásitos es el estómago (75.5%). La principal medida preventiva contra las parasitosis más conocidas es lavarse las manos (67.9%). Conclusión: muchos participantes creen que los humanos se pueden infectar por los mismos parásitos de los animales. Los piojos fueron los parásitos más conocidos y las garrapatas las menos conocidas. La mayoría considera el vómito o la diarrea como los síntomas principales de las parasitosis y creen que el estómago es el más afectado en una infección. Además, señalan que la principal medida preventiva para evitar el contagio es el lavado de manos.

Objective: parasites are organisms that live inside or on another species for their own benefit, managing to affect plants, animals, and humans. Children are more vulnerable to infection, but the incidence has decreased thanks to the improvement in Costa Rican sanitation. The aim was to evaluate the general knowledge that the Costa Rican population has regarding childhood parasitosis. Methodology: an observational, descriptive, cross-sectional study was carried out on a sample of 196 subjects. A survey was conducted among Costa Ricans over 18 years of age who had a device with internet access. The participants were asked about their knowledge on the clinical picture of childhood parasitosis in Costa Rica. Results: most of the participants were college students (68.3%). 89.9% of them believe that pet parasites can infect humans. The best-known parasites were lice, marked by 173 (88.3%) people. The stomach is the part of the body considered most affected, with 148 (75.5%) responses. The main known preventive measure is washing hands with soap and water, answered by 133 participants (67.9%). Conclusion: Many participants believe that humans can be infected by the same parasites as animals. Lice were the best known and ticks the least. Most of the people consider vomiting and/or diarrhea as one of the main symptoms and believe that the stomach is the most affected part during the infection. In addition, they consider that the main preventive measure to avoid contagion is hand washing.

Objetivo: Parasitas são organismos que vivem em ou sobre outra espécie para seu próprio benefício. Eles conseguem afetar plantas, animais e humanos. As crianças são mais vulneráveis à infecção, mas a incidência diminuiu na Costa Rica graças a melhorias no saneamento. O objetivo deste estudo foi avaliar o conhecimento geral que a população costarriquenha tem sobre parasitas infantis.Metodologia: estudo observacional, descritivo, transversal, com amostra de 196 sujeitos.Uma pesquisa foi apresentada a costarriquenhos maiores de 18 anos que possuíam um dispositivo com acesso à internet. O conhecimento do quadro clínico de parasitas infantis na Costa Rica foi consultado.Resultados:a maioria dos participantes era universitária (68.3%). 89.9% acreditam que parasitas de animais de estimação podem infectar humanos. Os parasitas mais conhecidos foram os piolhos 173 (88.3%). A parte do corpo considerada mais afetada pelos parasitas é o estômago (75.5%). A principal medida preventiva contra os parasitas mais conhecidos é a lavagem das mãos (67.9%).Conclusão: muitos participantes acreditam que humanos podem ser infectados pelos mesmos parasitas de animais. Os piolhos foram os parasitas mais conhecidos e os carrapatos os menos conhecidos. A maioria considera vômito ou diarreia como os principais sintomas dos parasitas e acredita que o estômago é o mais afetado em uma infecção. Além disso, apontam que a principal medida preventiva para evitar o contágio é a lavagem das mãos.

Avaliação soroepidemiológica de cães expostos a Rickettsia parkeri e correlação com a estrutura da paisagem no litoral do estado de São Paulo / Serosurvey on dogs for Rickettsia parkeri and correlation with landscape structure in São Paulo state coast (Brazil)

A febre maculosa causada por Rickettsia parkeri é a segunda riquetsiose de maior importância no Brasil. No estado de São Paulo, o agente é transmitido pelo carrapato Amblyomma ovale, que ocorre em número elevado em regiões costeiras de Mata Atlântica. Até o presente momento, não foi estabelecido como a estrutura da paisagem pode afetar a dispersão de carrapatos infectados por R. parkeri e, portanto, dinâmica de transmissão da doença. Propõe-se avaliar a relação entre a sorologia de cães domésticos expostos a R. parkeri e a estrutura da paisagem em áreas de comunidades adjacentes à Mata Atlântica no litoral paulista. Em um estudo transversal, foram selecionadas cinco áreas localizadas nos municípios de Cubatão, Peruíbe, São Sebastião, Cananéia e Ilhabela e, em cada área, amostras de soro de 30 cães foram colhidas e submetidas a reação de imunofluorescência indireta para detecção do título máximo de anticorpos anti-R. parkeri. Spearman foi usado como teste de correlação entre a sorologia e os componentes principais extraídos das métricas de paisagem em cada área de estudo. A análise da estrutura da paisagem evidenciou dois componentes principais não correlacionados que, somados, explicam 94,77% da variabilidade entre as áreas, em que o primeiro componente está relacionado à conectividade e o segundo componente está relacionado à quantidade de borda. A soroprevalência das áreas variou de 16,7% a 83,3%. A exposição de cães domésticos a R. parkeri está associada positivamente com a conectividade de habitat para A. ovale em áreas estudadas do litoral do estado de São Paulo. Não foi evidenciada associação entre a sorologia e a quantidade de borda na paisagem. É recomendado que as ações de vigilância epidemiológica para febre maculosa por R. parkeri sejam priorizadas em áreas com maior conectividade florestal, juntamente com a conscientização da posse responsável de cães.

Spotted fever caused by Rickettsia parkeri is the second most important rickettsiosis in Brazil. In São Paulo state, this agent is transmitted by the Amblyomma ovale tick, highly prevalent in coastal Atlantic Rainforest. Until the present moment, it is not known how landscape structure could affect A. ovale dispersion, and therefore, R. parkeri transmission dynamics. It is proposed to evaluate the seroepidemiology from R. parkeri exposed dogs and its correlation with landscape structure in São Paulo state coast. A transversal study was conducted to evaluate five different areas from communities nearby Atlantic Rainforest (municipalities of Cubatão, Peruíbe, São Sebastião, Cananéia and Ilhabela). Within each area, blood samples from 30 dogs were collected for serologic testing by indirect immunofluorescence assay. Correlation test Spearman was used between serology data and principal components extracted from landscape structure metrics in each area. Principal components analysis pointed two principal uncorrelated components which, together, explain 94,77% of the variability between landscape metrics. First component is related to landscape connectivity, and the second is related to edge abundance. It was found a seroprevalence from 16,7% to 83,3% in the different areas. A positive association between antibodies anti-R. parkeri found in dogs and landscape connectivity (p=0) was demonstrated. There was no association between serologic testing and edge abundance in the study areas. It is recommended that R. parkeri rickettsiosis surveillance to be priorized in connected forest areas, and responsible dog ownership must be encouraged.

Avaliação da competência de cães domésticos como hospedeiros amplificadores da bactéria Rickettsia rickettsii para carrapatos Amblyomma aureolatum e modelagem espacial ecológica preditiva para ocorrência de Febre Maculosa Brasileira no Estado de São Paulo / Evaluation of domestic dogs as competent amplifier hosts of the bacterium Rickettsia rickettsii for Amblyomma aureolatum ticks and predictive spatial ecological modeling for the occurrence of Brazilian Spotted Fever in the State of São Paulo

A Febre Maculosa Brasileira (FMB) é uma zoonose transmitida por vetores que tem como agente patogênico, bactérias da espécie Rickettsia rickettsii. Na Região Metropolitana de São Paulo (RMSP), o vetor incriminado na transmissão é o carrapato Amblyomma aureolatum, que depende de características ambientais típicas do bioma Mata Atlântica para sobreviver. Cães domésticos são os principais hospedeiros do estágio adulto do carrapato em áreas de matriz urbana próxima a áreas de mata fragmentada, e participam do ciclo da doença ao carrear carrapatos infectados da mata para o ambiente antrópico. Além disso, são hospedeiros amplificadores do agente e contribuem para o aumento do número de carrapatos infectados na natureza. Com o objetivo de elucidar as lacunas em relação a FMB na RMSP, o presente estudo testou a hipótese de que cães domésticos atuariam como hospedeiros amplificadores da bactéria R.rickettsii para carrapatos da espécie A. aureolatum após um segundo contato com o agente. Os resultados mostraram que apesar de apresentarem uma resposta imunológica, com aumento no título de anticorpos, os cães não foram capazes de gerar novas linhagens de carrapatos infectados. Esse estudo determinou, por meio de modelagem espacial, quais as áreas mais ou menos propensas a apresentarem casos de FMB levando em consideração as condições necessárias para ocorrência do vetor A. aureolatum e os aspectos ecológicos que facilitam a interação do vetor com seus hospedeiros no ambiente. As variáveis ambientais de altitude e temperatura mostraram-se de maior influência para a distribuição do vetor enquanto o aumento do perímetro de borda e redução de áreas de mata favorecem a ocorrência de casos de FMB. Este estudo traz novos dados sobre a ecoepidemiologia da Febre Maculosa Brasileira no Estado de São Paulo e chama atenção para a importância dos cães domésticos no ciclo da doença que ocorre na Região Metropolitana do estado. Ações de prevenção com foco na população de cães se mostram de extrema importância para a redução da incidência da doença e melhoria das condições de saúde da população.

Brazilian Spotted Fever (BSF) is a vector-borne zoonosis whose agent is the bacteria Rickettsia rickettsii. In the São Paulo Metropolitan Region (SPMR), the vector responsible for the disease transmission is the tick Amblyomma aureolatum, which depends on environmental characteristics of the Atlantic Forest biome to survive. Domestic dogs are the main hosts of the adult stage of the tick in areas of urban matrix close to fragmented forest, and participate in the disease cycle by carrying infected ticks from the forest to the anthropic environment. Furthermore, they can amplify the bacteria and contribute to increase the number of infected ticks in nature. In order to elucidate the gaps in relation to BSF in the SPMR, this study tested the hypothesis that dogs could act as amplifying hosts of R. rickettsii for A. aureolatum ticks after a second contact with the agent. The results showed that the dogs could not generate new infected tick strains despite an immune response with increased antibody titers. This study also determined, through spatial modeling, which areas are more likely to present cases of BSF, taking into account the necessary conditions for A. aureolatum occurrence and the ecological aspects that facilitate the interaction of the vector with its hosts in the environment. The environmental variables of altitude and temperature showed to have the greatest influence on vector distribution, while the increase in edge perimeter and decrease in forest cover favored the occurrence of BSF. This study brings new data on the ecoepidemiology of Brazilian Spotted Fever in the State of São Paulo and draws attention to the importance of domestic dogs in the disease cycle in the Metropolitan Region of the state. Prevention actions focused on dog population are extremely important to reduce disease incidence and improve the human population's health conditions.

Diversity of tick species (Acari: Ixodidae) in military training areas in Southeastern Brazil / Diversidade de espécies de carrapatos (Acari: Ixodidae) em áreas de instrução militar na região Sudeste do Brasil

Abstract Tick-borne pathogens belong to one of the two main groups of occupational biohazards, and occupational exposure to such agents puts soldiers at risk of zoonotic infections, such as those caused by rickettsiae. There are few studies on acarological fauna and occupational risk in military areas in Brazil. Thus, the present study aimed to analyze the diversity of ticks present in the military training areas of municipalities in the Southeast Region of Brazil. The ticks were collected from the selected areas using the dragging and flagging techniques as well as by visual detection on the operators' clothing, and environmental information was also recorded. A total of ten species were collected from the 66 surveyed areas, belonging to five genera and nine species: Amblyomma sculptum, Amblyomma dubitatum, Amblyomma brasiliense, Amblyomma longirostre, Amblyomma aureolatum, Dermacentor nitens, Rhipicephalus spp., Ixodes spp. and Haemaphysalis spp. The frequent presence of tick species in military training areas along with traces and sightings of wild animals, most commonly capybaras (Hydrochoerus hydrochaeris), in most of the studied areas, indicates high levels of exposure of the military to tick vectors of spotted fever group rickettsiae and the possible occurrence of infections among the troops.

Resumo As doenças transmitidas por carrapatos estão entre os dois principais grupos de riscos biológicos ocupacionais. Tal exposição ocupacional de militares os colocam sob maior risco de adquirirem doenças zoonóticas, como infecções rickettsiais, entre outras. No Brasil, há raros estudos sobre fauna acarológica e o risco ocupacional em áreas militares. Neste sentido, o presente estudo teve por objetivo analisar a diversidade de carrapatos presentes em áreas de treinamento militar de municípios da região Sudeste do Brasil. Os carrapatos foram coletados nas áreas através de arrasto de flanela, bandeiramento e/ou coleta nas vestimentas do operador, sendo registradas também informações ambientais. Das 66 áreas pesquisadas, foram coletados 9.374 carrapatos, com uma diversidade de cinco gêneros, distribuídos em dez espécies: Amblyomma sculptum, Amblyomma dubitatum, Amblyomma brasiliense, Amblyomma longirostre, Amblyomma aureolatum, Amblyomma spp., Dermacentor nitens, Rhipicephalus spp., Ixodes spp. e Haemaphysalis spp. A presença frequente de espécies de carrapatos nas áreas de instrução militar, associada aos vestígios e à presença de animais silvestres, mais comumente de capivaras na maioria das áreas estudadas, evidencia uma grande exposição dos militares a carrapatos vetores de rickettsias do Grupo da Febre Maculosa e a possível ocorrência de casos humanos nas tropas.

Molecular detection of anaplasmataceae agents on dogs from the departament of Piura, Peru

This study aimed to study the prevalence of Anaplasmataceae organisms through the nested-PCR and phylogenetic analysis on domestic dogs in the Department of Piura, Peru. Two hundred and twelve canine blood samples were randomly collected on dogs from the central urban areas at the Piura Department in Peru. The extracted DNAs were tested, by nested-PCR based on 16SrRNA gene, to identify agents from Anaplasmataceae family. These results show that there was a prevalence of 18.5% (40/216) of positive dogs, 13.8% (30/216) for Ehrlichia canis, 7.4% (16/216) for Anaplasma platys and 0.1% (2/216) for Ehrlichia sp. confirmed by sequencing analysis. Co-positivity among Anaplasmataceae family species was present in 25% (10/40) of positive samples. There was a significant association among Anaplasmataceae family infection in dogs and the following variables: sex (p=0.034), presence of ticks (p=0.0001), and socio-economic status (p=0.001). There was no statistical association on the variables "living with other animals" and "age group" (p=0.1074). The partial sequences on the portion of the 16S rRNA gene, from positive samples for agents of Anaplasmataceae family demonstrated an identity of 97-100% with the isolated E. canis and A. platys obtained from the GenBank. This is the first study on infection by agents of Anaplasmataceae family in dogs in the Department of Piura, through molecular analysis

Seroprevalence and hematological abnormalities associated with Ehrlichia canis in dogs referred to a veterinary teaching hospital in central-western Brazil / Soroprevalência e alterações hematológicas associadas com Ehrlichia canis em cães encaminhados a um hospital veterinário-escola no centro-oeste do Brasil

Ticks are significant parasites of dogs in the tropics, where tick-borne pathogens are highly prevalent, especially in areas where tick control measures are frequently neglected. This study investigated the seroprevalence and hematological abnormalities associated with Ehrlichia canis in dogs referred to a veterinary teaching hospital in Central-western Brazil. Out of 264 dogs tested for anti-Ehrlichia canis antibodies by an indirect immunofluorescence assay (IFA), 59.1% (156/264) were positive. Seropositivity was significantly associated to anemia and thrombocytopenia, alone or in combination, and to leukopenia. Conversely, there were no differences in terms of seroprevalence according to sex, breed and age. This study demonstrated that dogs referred to a veterinary teaching hospital in Central-western Brazil are highly exposed to E. canis and that seropositive dogs are more likely to present hematological abnormalities, particularly anemia, thrombocytopenia and leukopenia. To our knowledge, this is the first study on detection of anti-E. canis antibodies by means of IFA among dogs in the state of Goiás. These findings highlighted the need for increasing awareness among dog owners regarding tick control measures in Central-western Brazil, ultimately to reduce the risk of exposure to E. canis and other tick-borne pathogens.

Carrapatos são importantes parasitos de cães nos trópicos, onde patógenos transmitidos por carrapatos são altamente prevalentes, especialmente em áreas onde as medidas de controle de carrapatos são frequentemente negligenciadas. O estudo investigou a soroprevalência e as anormalidades hematológicas associadas à Ehrlichia canis em cães encaminhados para um hospital veterinário-escola no Centro-oeste do Brasil. Dos 264 cães testados para anticorpos anti-Ehrlichia canis por meio da reação de imunofluorescência indireta (RIFI), 59.1% (156/264) foram positivos. A soropositividade foi associada significativamente à anemia e trombocitopenia, isoladamente ou em combinação, e à leucopenia. Por outro lado, não houve diferenças quanto à soroprevalência segundo sexo, raça e idade. Este estudo demonstrou que cães encaminhados a um hospital veterinário-escola na região Centro-oeste do Brasil são altamente expostos à E. canis, e que cães soropositivos têm maior probabilidade de apresentar alterações hematológicas, principalmente anemia, trombocitopenia e leucopenia. Para o nosso conhecimento, este é o primeiro estudo sobre a detecção de anticorpos anti-E. canis por meio da RIFI em cães do estado de Goiás. Essas descobertas destacam a necessidade de aumentar a conscientização entre os proprietários de cães em relação às medidas de controle do carrapato no Centro-oeste do Brasil, em última análise, para reduzir o risco de exposição ao E. canis e outros patógenos transmitidos por carrapatos.

Assessment of weight gain and control of parasitism by Rhipicephalus microplus in dairy cattle in the field using organosynthetic parasiticide, phytotherapics and homeopathy / Avaliação do ganho de peso e controle do parasitismo por Rhipicephalus microplus em bovinos leiteiros a campo usando parasiticida organosintético, fitoterápicos e homeopatia

The goal of this research was to compare the effect of the following products on dairy cattle, parasitized by Rhipicephalus microplus: organosynthetics - Clorfenvinfós and Ivermectina (OG); phytotherapics - Eucalyptus oil (EG) and Neem cake (NG); Homeopathy (HG); The control group (CG) received no treatment. Infestation was by R. microplus (MIC) and weight gain (GP) were evaluated. The study included 60 animals (5 groups) from ­ Dutch / Zebu, aged between 25-44 months and initial weight between 211-477kg. EG and NG showed MIC 84.9% and 14.0% greater than CG, respectively (P <0.05; P = 0). HG and OG had MIC less than CG 24.4% and 16.9%, respectively (P<0.05; P <0.05). EG, NG and OG obtained GP lower than CG in 7.9%, 8.9% and 8.06% (P <0.05) respectively. The HG GP was 4.9% higher (P <0.05) than CG. This was the first research to prove parasitism control by R. microplus in a field test, using homeopathy. The methodology for choosing Homeopathy for the control of enzooties, developed and tested for the first time in this study, proved to be adequate and efficient, opening the possibility for establishing a new methodology for strategic control of parasitism by R. microplus.(AU)

O objetivo desta pesquisa foi comparar o efeito dos seguintes produtos sobre bovinos leiteiros, parasitados por Rhipicephalus microplus: organossintéticos - clorfenvinfós e ivermectina (OG); fitoterápicos - óleo de eucalipto (EG) e torta de Neem (NG) e homeopatia (HG). O grupo controle (CG) não recebeu tratamento. Foram avaliados infestação por R. microplus (MIC) e ganho de peso/grupo (GP) em 60 animais (5 grupos), a partir de ­ holandês/zebu, com idade entre 25 e 44 meses e peso inicial entre 211 e 477kg. EG e NG apresentaram MIC 84,9% e 14,0% maior que CG, respectivamente (P<0,05; P=0). HG e OG apresentaram MIC menor que CG 24,4% e 16,9%, respectivamente (P<0,05; P<0,05). EG, NG e OG obtiveram GP menor que CG em 7,9%, 8,9% e 8,06% (P<0,05), respectivamente. O GP do HG foi 4,9% maior (P<0,05) que o CG. Esta foi a primeira pesquisa a comprovar controle do parasitismo por R. microplus em teste a campo, usando homeopatia. A metodologia para escolha de medicamentos homeopáticos para controle de enzootias, desenvolvida e testada pela primeira vez neste estudo, mostrou-se adequada e eficiente, abrindo a possibilidade para estabelecimento de nova metodologia para controle estratégico do parasitismo por R. microplus.(AU)