Tick-associated diseases identified from hunting dogs during the COVID-19 pandemic in a Mayan community in Yucatan, Mexico.

Background: Hunting activity in the Mayan communities has increased due to COVID-19 and domestic dogs have gained more importance. Due to their proximity to humans, domestic dogs are a bridge between tick-borne diseases (TBDs) and humans and their peri-domestic environment. In Mexico, and especially in rural regions, there were not adequate records of TBDs during the SARS-CoV-2 pandemic. Aim: Identify TBD of ticks collected during the COVID-19 pandemic in a rural community. Methods: Tick capture was carried out in March 2021, in Teabo, Yucatan. Ticks were removed using from domestic dogs and placed in ethanol. Collected ticks were morphologically identified and underwent DNA extraction and a partial segment of the mitochondrial 16S-rDNA gene was amplified to corroborate the tick species. The DNA was screened for the presence of Anaplasma spp., Borrelia spp., Ehrlichia spp., and Rickettsia spp. Purified amplification products were submitted for sequencing and the results were compared to those deposited in GenBank using BLAST. Results: We collected 33 ectoparasites, Ixodes affinis, Rhipicephalus sanguineus, Rhipicephalus microplus, and Amblyomma mixtum on 11 hunting dogs. The most frequent ectoparasite was R. sanguineus (66%). We detected the presence of DNA of Rickettsia endosymbiont in I. affinis and Anaplasma platys in R. sanguineus. Rickettsia endosymbiont presented a similarity of 100% with the partial sequence of R. endosymbiont of I. affinis isolate IACACTM001 16S ribosomal RNA gene and the sequence of A. platys had a similarity of 100% with the partial sequence of the isolate 23-33TX 16S ribosomal RNA gene of A. platys from dogs from Texas, USA and with the partial sequence of the isolate L134 16S ribosomal RNA gene of Ehrlichia canis from dogs from Piura, Peru. Conclusion: We confirmed for the first time the presence of A. platys in R. sanguineus and R. endosymbiont in I. affinis ticks from dogs in the state of Yucatan.

Epidemiological link between canine monocytic ehrlichiosis caused by Ehrlichia canis and the presence of Rhipicephalus sanguineus sensu stricto in Argentina.

In this work, we analyze data that support an epidemiological link between cases of canine monocytic ehrlichiosis (CME) by Ehrlichia canis and the presence of Rhipicephalus sanguineus sensu stricto as vector in an endemic area for this tick in Argentina. In a blood sample of a 1-year-old toy poodle with CME compatible clinical signs, which showed CME typical morulae in monocytes in Giemsa-stained blood smear, DNA of E. canis was detected by PCR. Further, DNA of E. canis was also detected in a female of R. sanguineus s.s. collected on the infected dog. Rhipicephalus sanguineus s.s. is the only member of the R. sanguineus group that prevails in the study area. The results of this study suggest that R. sanguineus s.s. may play a more important role in the transmission of E. canis than it was assumed so far. The epidemiological link between CME cases and R. sanguineus s.s. as vector in temperate areas of Argentina described in this work contrast previous studies which found that R. sanguineus sensu lato "tropical lineage" (which is absent in the study area) is competent to transmit E. canis but not R. sanguineus s.s.

Molecular detection of Cercopithifilaria bainae and other tick-borne pathogens in Rhipicephalus sanguineus s.l. isolated from dogs in Midwest Brazil.

The aim of the present study was to detect Cercopithifilaria bainae and other tick-borne pathogens and to perform molecular characterization of the tick Rhipicephalus sanguineus s.l. collected from dogs. Ticks (n = 432, including 8 larvae, 59 nymphs, and 365 adults) were sampled from domiciled dogs (n = 73) living in Campo Grande, Mato Grosso do Sul (Midwest Brazil). All ticks were morphologically identified as R. sanguineus. Genomic DNA was extracted in pools (three to five ticks per animal) and was used for definition of R. sanguineus haplotypes (based on 16S rRNA analysis) and pathogen identification (Cercopithifilaria sp., Ehrlichia canis, Anaplasma platys, Hepatozoon canis, Babesia vogeli and Rickettsia spp.). Rhipicephal us sanguineus specimens were identified as haplotypes A and B. DNA of Cercopithifilaria bainae (43.83%; 32/73), Ehrlichia canis (24.65%; 18/73), Anaplasma platys (19.17%; 14/73), and Hepatozoon canis (5.47%; 4/73) was detected. The identity of pathogens was confirmed by DNA sequence analysis. The present study confirms the presence of haplotypes A and B of R. sanguineus in the state of Mato Grosso do Sul and its importance as a vector of several pathogens of veterinary concern. Finally, this is the first report to identify C. bainae in ticks in the Midwestern region of Brazil.

Molecular detection of Cercopithifilaria bainae and other tick-borne pathogens in Rhipicephalus sanguineus s.l. isolated from dogs in Midwest Brazil / Detecção molecular de Cercopithifilaria bainae e outros patógenos transmitidos por carrapatos em Rhipicephalus sanguineus s.l. isolados de cães no Centro-Oeste do Brasil

Abstract The aim of the present study was to detect Cercopithifilaria bainae and other tick-borne pathogens and to perform molecular characterization of the tick Rhipicephalus sanguineus s.l. collected from dogs. Ticks (n = 432, including 8 larvae, 59 nymphs, and 365 adults) were sampled from domiciled dogs (n = 73) living in Campo Grande, Mato Grosso do Sul (Midwest Brazil). All ticks were morphologically identified as R. sanguineus. Genomic DNA was extracted in pools (three to five ticks per animal) and was used for definition of R. sanguineus haplotypes (based on 16S rRNA analysis) and pathogen identification (Cercopithifilaria sp., Ehrlichia canis, Anaplasma platys, Hepatozoon canis, Babesia vogeli and Rickettsia spp.). Rhipicephal us sanguineus specimens were identified as haplotypes A and B. DNA of Cercopithifilaria bainae (43.83%; 32/73), Ehrlichia canis (24.65%; 18/73), Anaplasma platys (19.17%; 14/73), and Hepatozoon canis (5.47%; 4/73) was detected. The identity of pathogens was confirmed by DNA sequence analysis. The present study confirms the presence of haplotypes A and B of R. sanguineus in the state of Mato Grosso do Sul and its importance as a vector of several pathogens of veterinary concern. Finally, this is the first report to identify C. bainae in ticks in the Midwestern region of Brazil.

Resumo O objetivo do presente estudo foi detectar Cercopithifilaria bainae e outros patógenos transmitidos por carrapatos e realizar a caracterização molecular do carrapato Rhipicephalus sanguineus s.l. coletado em cães. Carrapatos (n = 432, incluindo 8 larvas, 59 ninfas e 365 adultos) foram amostrados de cães domiciliados (n = 73) residentes no município de Campo Grande, Mato Grosso do Sul (centro-oeste do Brasil). Todos os carrapatos foram identificados morfologicamente como R. sanguineus. O DNA genômico foi extraído em pools (três a cinco carrapatos por animal), seguido pela definição de haplótipos (com base no gene 16S rRNA) e pela investigação de patógenos (Cercopithifilaria sp., Ehrlichia canis, Anaplasma platys, Hepatozoon canis, Babesia vogeli e Rickettsia spp.). Os espécimes coletados foram identificados como haplótipos A e B de R. sanguineus. Foram detectados DNA de Cercopithifilaria bainae (43,83%; 32/73), Ehrlichia canis (24,65%; 18/73), Anaplasma platys (19,17%; 14/73) e Hepatozoon canis (5,47%; 4/73). A identidade dos patógenos foi confirmada por análise de sequência de DNA. O presente estudo confirma a circulação dos haplótipos A e B de R. sanguineus no estado de Mato Grosso do Sul e sua importância como vetor de vários patógenos de interesse veterinário. Finalmente, este é o primeiro relato de C. bainae em carrapatos na região centro-oeste do Brasil.

First detection and genetic identification of Hepatozoon canis in Rhipicephalus sanguineus sensu lato ticks collected from dogs of Taiwan.

We determined the prevalence of infection and genetic identity of Hepatozoon spp. harbored by Rhipicephalus sanguineus sensu lato ticks in Taiwan. A total of 1082 ticks were collected from dogs and DNA extraction was performed from individual tick specimens. Hepatozoon infection was detected by performing a nested-PCR assay based on the 18S small subunit ribosomal RNA (ssrRNA) gene. The genetic identity of detected Hepatozoon was identified by gene sequencing and phylogenetic analysis. Hepatozoon infection was detected in nymphs, males and females of R. sanguineus s. l. ticks with an infection rate of 20.8%, 22.8% and 29.4%, respectively. Sequence and phylogenetic analysis revealed that these Hepatozoon spp. of Taiwan were genetically affiliated to the same clade within the genospecies of H. canis and can be discriminated from other genospecies of H. americanum and H. felis. Intraspecies analysis based on the genetic distance (GD) values indicates a lower level (GD < 0.005) genetic divergence within the same genospecies of H. canis detected in Taiwan, Brazil and Spain. Interspecies analysis also reveals a higher heterogeneity of Taiwan strains distinguished from other genospecies of H. felis (GD > 0.040) and H. americanum (GD > 0.056). This study provides the first molecular evidence of H. canis detected and identified in various stages of R. sanguineus s. l. ticks in Taiwan. Detection of H. canis in unfed male ticks may imply the possible mechanism of transstadial survival in R. sanguineus s. l. ticks. Further investigations on Hepatozoon spp. harbored by various vector ticks in Taiwan may illustrate the epidemiological significance of this parasite.

Persistence and efficacy of a new formulation based on dog allomonal repellents against Rhipicephalus sanguineus sensu lato tick / Persistência e eficácia de uma nova formulação baseada em repelentes alomônios de cães contra o carrapato Rhipicephalus sanguineus sensu lato

Beagles are less susceptible to Rhipicephalus sanguineus sensu lato tick due to the production of the allomones benzaldehyde and 2-hexanone. Our previous published work showed that these compounds can reduce tick burden on susceptible dogs. Here we tested the hypothesis that an increase in repellent dose and release rate could increase repellent efficacy and persistence. Slow-release formulations of these compounds, with higher doses and release rates, were tested on artificially-infested dogs. Ten dogs were randomly assigned to two groups with five dogs each. The treated group received collars with slow-release formulations of the compounds attached, while the control group received collars with clean formulations attached. Five environmental infestations were performed, with the number of ticks (at all stages) on the dogs being counted once a day for 40 days. No significant increase in repellent efficacy was observed with the higher doses and release rates, whereas a greater persistence in repellent activity was observed. Treatment with the formulations resulted in a two-to-three-fold reduction in the number of immature stage ticks for up to three weeks. However, the number of adults was similar in both groups. Loss of repellent activity after the third week of testing coincided with a marked change in the relative release rates for the two compounds. It is hypothesized that relative amounts, rather than absolute amounts, of repellent release from slow-release formulations are important for repellent activity. We also hypothesize that the avoidance of less-preferred hosts by ticks relies on olfactory-mediated perception of specific blends of volatile cues from less preferred hosts.(AU)

Beagles são menos suscetíveis ao carrapato Rhipicephalus sanguineus sensu lato devido à produção de benzaldeído e 2-hexanona. Nosso trabalho anterior já publicado mostrou que esses compostos podem reduzir a carga de carrapatos em cães suscetíveis. Aqui testamos a hipótese de que um aumento na dose destes repelentes e na taxa de liberação poderia aumentar a eficácia e a persistência do efeito repelente. As formulações de liberação lenta destes compostos, com doses e taxas de liberação mais elevadas foram testadas em cães infestados artificialmente. Dez cães foram distribuídos aleatoriamente em dois grupos com cinco cães cada. O grupo tratado recebeu colares contendo formulações de liberação lenta dos compostos, enquanto o grupo controle recebeu colares com formulações limpas. Cinco infestações ambientais foram realizadas, com o número de carrapatos (em todas as fases) nos cães sendo contados, uma vez ao dia, por 40 dias. Não se observou aumento significativo na eficácia do repelente com doses e taxas de liberação mais elevadas e, enquanto observou-se maior persistência na atividade repelente. O tratamento com as formulações resultou em uma redução de duas a três vezes no número de carrapatos dos estágios imaturos, por até três semanas. No entanto, o número de adultos foi semelhante em ambos os grupos. A perda de atividade repelente após a terceira semana de teste coincidiu com uma mudança nas taxas de liberação relativa para os dois compostos. A hipótese é que as quantidades relativas, ao invés das quantidades absolutas de liberação lenta, são importantes para a atividade repelente. Então, a hipótese é de que a repelência apresentada por hospedeiros menos susceptíveis aos carrapatos depende da percepção pelos carrapatos de misturas específicas de voláteis liberados por estes hospedeiros.(AU)

Screening of Cercopithifilaria bainae and Hepatozoon canis in ticks collected from dogs of Northeastern Brazil.

Rhipicephalus sanguineus sensu lato (s.l.) is one of the most widespread ixodid ticks and is a competent vector of several vector-borne pathogens of veterinary and medical concern. For instance, this tick species transmits nematodes of the genus Cercopithifilaria and protozoa of the genus Hepatozoon to carnivores, including dogs. Here we investigated the occurrence of Cercopithifilaria spp. and Hepatozoon spp. in a population of ticks collected from naturally infested dogs living in rural areas of Northeastern Brazil. From August 2016 to June 2017, 758 tick specimens (mean ticks per month = 68.9 ± 71.4) were sampled from 75 dogs (mean ticks per dog = 10.11 ± 5.2) and dissected under a stereomicroscope in order to visualize Cercopithifilaria spp. larvae and Hepatozoon spp. oocysts and sporocysts. R. sanguineus s.l. was the only species collected, peaking in September (n = 273) and decreasing in February 2017 (n = 39). Different larval stages of Cercopithifilaria bainae were identified in 7 out of 758 (0.93%) ticks. In addition, 4 specimens (0.53%) were positive for oocysts and free sporocysts of Hepatozoon canis. The identity of both species of parasites was molecularly confirmed. These results account for the predominance of R. sanguineus (s.l.) in domestic dogs from rural locations of the study area, as well as for the presence C. bainae and H. canis in these tick populations.

Cercopithifilaria bainae in Rhipicephalus sanguineus sensu lato ticks from dogs in Brazil.

Rhipicephalus sanguineus sensu lato (s.l.) ticks act as intermediate host for a range of canine vector-borne pathogens, including nematodes ranked in the genus Cercopithifilaria. Though being the object of several studies in the last years, information on the distribution of these parasites is still lacking. In this study, the occurrence of Cercopithifilaria spp. was investigated in on-host population of R. sanguineus s.l. collected from naturally infested dogs. Ticks (n=1906, including one larva, 294 nymphs and 1611 adults) were sampled on domestic dogs (n=155) living in the municipality of Garanhuns (northeastern Brazil). Tick collections (n=36) were performed every 8 days, from October 2015 to June 2016. Filarioid larvae detected at tick dissection were morphologically and morphometrically identified at species level. At the end of the study, only R. sanguineus s.l. ticks were collected, with the highest number in January 2016 (n=254) and the lowest in June 2016 (n=26). Out of 1906 dissected ticks, 2.68% (51/1906) harboured Cercopithifilaria bainae larvae, whose identification was molecularly confirmed, with a nucleotide identity of 99% with C. bainae. Data here reported indicate that, in the study area, R. sanguineus s.l. is the predominant tick infesting domestic dogs. Accordingly, these animals are at a high risk of C. bainae infection.

Larvae of Ixodiphagus wasps (Hymenoptera: Encyrtidae) in Rhipicephalus sanguineus sensu lato ticks (Acari: Ixodidae) from Brazil.

The biological control of ticks represents an alternative method to the chemical control, given its ecological-friendly approach. Amongst the alternatives, the use of parasitoids of the genus Ixodiphagus (Hymenoptera: Encyrtidae) has been largely investigated. The aim of this study was to document and molecularly characterize Ixodiphagus wasps in ticks from a tropical region of Brazil. From October 2015 to March 2016, Rhipicephalus sanguineus sensu lato ticks (n=1814) were collected from naturally infested dogs and Ixodiphagus larvae were detected by microscopic examination. In addition, adult wasps were obtained in the laboratory. Larvae and adults were molecularly identified as Ixodiphagus hookeri. These findings suggest that this type of parasitism deserves to be studied in local tick populations, in order to elucidate the role of these wasps as a potential alternative to chemical tick control.

Using plastic tips in artificial feeding of Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) females / Uso de ponteiras plásticas na alimentação artificial de fêmeas de Rhipicephalus sanguineus

This study evaluated the influence of the initial weight, feeding period and temperature on weight gain and biological parameters of the non-parasitic phase of partially engorged Rhipicephalus sanguineus females that were artificially fed using plastic tips as feeding devices. The device did not alter the oviposition of the females or any other parameters evaluated. Furthermore, it was observed that the temperature of the feeding the group did not affect the weight gain and biology of ticks. This device has great potential for the development of studies on bioagent transmission because it provides higher intake of blood by ixodid ticks.(AU)

Este estudo avaliou a influência do peso inicial, período de alimentação e temperatura no ganho de peso e parâmetros biológicos da fase não parasitária, de fêmeas parcialmente ingurgitadas de Rhipicephalus sanguineus alimentadas artificialmente utilizando ponteiras plásticas como dispositivo de alimentação. O dispositivo não alterou a oviposição das fêmeas ou quaisquer outros parâmetros avaliados. Além disso, observou-se que a temperatura de alimentação do grupo não afetou o ganho de peso e a biologia dos carrapatos. Este dispositivo tem um grande potencial para o desenvolvimento de estudos sobre a transmissão de bioagentes, uma vez que proporciona maior ingestão de sangue por carrapatos ixodídeos.(AU)

Ehrlichia canis DNA in domestic cats parasitized by Rhipicephalus sanguineus sensu lato (s. l. ) ticks in Brazil ­ case report / Felinos domésticos parasitados por carrapato Rhipicephalus sanguineus sensu lato (s. l. ) infectados por Ehrlichia canis no Brasil ­ relato de caso

Ectoparasites can transmit pathogens, including bacteria such as Ehrlichia sp., which trigger infectious diseases in domestic animals. Little is known about the epidemiology of feline ehrlichiosis, although several studies have focused on elucidating the pathogenesis and transmission of this disease. This paper presents the first mutual infection by Ehrlichia sp. between a domestic cat and a Rhipicephalus sanguineus sensu lato (s.l.) tick removed from the animal. The cat and tick were tested by Polymerase Chain Reaction (PCR) to detect the dsb gene, and the analyzed sequences revealed samples 100% identical to E. canis. Based on this report, we discussed the importance of cats as E. canis reservoirs s and their position in the cycle of transmission between dogs and cats in Brazil.(AU)

Os ectoparasitos são capazes de transmitir patógenos incluindo algumas bactérias, como a Ehrlichia sp., causando doenças em animais domésticos. Pouco se conhece sobre a epidemiologia da erliquiose felina, embora alguns estudos já tenham sido realizados para elucidar a sua patogenia e transmissão. Este trabalho relata a primeira infecção mútua por Ehrlichia sp. entre um felino doméstico e o carrapato Rhipicephalus sanguineus sensu lato (s.l.) removido deste animal. Ambos foram testados pela Reação em Cadeia pela Polimerase (PCR) para detectar o gene dsb, e as sequências analisadas confirmaram amostras 100% idênticas à E. canis. Baseado neste relato é discutida a importância dos gatos como vetores de E. canis e sua posição no ciclo de transmissão de carrapatos entre cães e gatos no Brasil.(AU)

Human parasitism by Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) in Mato Grosso do Sul, West-Central Brazil / Parasitismo humano por Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) no Mato Grosso do Sul, Centro-Oeste do Brasil

Human parasitism by the brown dog tick Rhipicephalus sanguineus sensu lato (s. l.), an important parasite in medical and veterinary sciences, is only rarely reported in the American continent. The present investigation reports a R. sanguineus s. l. male tick parasitizing a human in the city of Campo Grande, State of Mato Grosso do Sul, west-central Brazil. This observation is of public health relevance, since R. sanguineus s. l. ticks are known as vectors of spotted fever group rickettsiae to dogs and humans.(AU)

O parasitismo humano pelo carrapato marrom do cão, Rhipicephalus sanguineus sensu lato (s. l.), um importante parasita para a saúde pública e veterinária, é raramente relatado no continente americano. Este trabalho relata o registro de um macho de R. sanguineus s. l. parasitando um humano na cidade de Campo Grande, estado do Mato Grosso do Sul, no Centro-Oeste do Brasil. Essa observação é relevante para a saúde pública, uma vez que os carrapatos desse complexo são conhecidos como vetores de riquétsias do grupo da febre maculosa para cães e humanos.(AU)

Ehrlichia canis DNA in domestic cats parasitized by Rhipicephalus sanguineus sensu lato (s. l. ) ticks in Brazil ­ case report / Felinos domésticos parasitados por carrapato Rhipicephalus sanguineus sensu lato (s. l. ) infectados por Ehrlichia canis no Brasil ­ relato de caso

Ectoparasites can transmit pathogens, including bacteria such as Ehrlichia sp., which trigger infectious diseases in domestic animals. Little is known about the epidemiology of feline ehrlichiosis, although several studies have focused on elucidating the pathogenesis and transmission of this disease. This paper presents the first mutual infection by Ehrlichia sp. between a domestic cat and a Rhipicephalus sanguineus sensu lato (s.l.) tick removed from the animal. The cat and tick were tested by Polymerase Chain Reaction (PCR) to detect the dsb gene, and the analyzed sequences revealed samples 100% identical to E. canis. Based on this report, we discussed the importance of cats as E. canis reservoirs s and their position in the cycle of transmission between dogs and cats in Brazil.(AU)

Os ectoparasitos são capazes de transmitir patógenos incluindo algumas bactérias, como a Ehrlichia sp., causando doenças em animais domésticos. Pouco se conhece sobre a epidemiologia da erliquiose felina, embora alguns estudos já tenham sido realizados para elucidar a sua patogenia e transmissão. Este trabalho relata a primeira infecção mútua por Ehrlichia sp. entre um felino doméstico e o carrapato Rhipicephalus sanguineus sensu lato (s.l.) removido deste animal. Ambos foram testados pela Reação em Cadeia pela Polimerase (PCR) para detectar o gene dsb, e as sequências analisadas confirmaram amostras 100% idênticas à E. canis. Baseado neste relato é discutida a importância dos gatos como vetores de E. canis e sua posição no ciclo de transmissão de carrapatos entre cães e gatos no Brasil.(AU)

Human parasitism by Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) in Mato Grosso do Sul, West-Central Brazil / Parasitismo humano por Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) no Mato Grosso do Sul, Centro-Oeste do Brasil

Human parasitism by the brown dog tick Rhipicephalus sanguineus sensu lato (s. l.), an important parasite in medical and veterinary sciences, is only rarely reported in the American continent. The present investigation reports a R. sanguineus s. l. male tick parasitizing a human in the city of Campo Grande, State of Mato Grosso do Sul, west-central Brazil. This observation is of public health relevance, since R. sanguineus s. l. ticks are known as vectors of spotted fever group rickettsiae to dogs and humans.(AU)

O parasitismo humano pelo carrapato marrom do cão, Rhipicephalus sanguineus sensu lato (s. l.), um importante parasita para a saúde pública e veterinária, é raramente relatado no continente americano. Este trabalho relata o registro de um macho de R. sanguineus s. l. parasitando um humano na cidade de Campo Grande, estado do Mato Grosso do Sul, no Centro-Oeste do Brasil. Essa observação é relevante para a saúde pública, uma vez que os carrapatos desse complexo são conhecidos como vetores de riquétsias do grupo da febre maculosa para cães e humanos.(AU)

Effect of heat stress and oil formulation on conidial germination of Metarhizium anisopliae s.s. on tick cuticle and artificial medium.

The effect of heat stress (45°C) versus non-heat stress (27°C) on germination of Metarhizium anisopliae sensu stricto (s.s.) isolate IP 119 was examined with conidia formulated (suspended) in pure mineral oil or in water (Tween 80, 0.01%), and then applied onto the cuticle of Rhipicephalus sanguineus sensu lato (s.l.) engorged females or onto culture medium (PDAY). In addition, bioassays were performed to investigate the effect of conidia heated while formulated in oil, then applied to blood-engorged adult R. sanguineus females. Conidia suspended in water then exposed to 45°C, in comparison to conidia formulated in mineral oil and exposed to the same temperature, germinated less and more slowly when incubated on either PDAY medium or tick cuticle. Also, conidial germination on tick cuticle was delayed in comparison to germination on artificial culture medium; for example, germination was 13% on tick cuticle 72h after inoculation, in contrast to 61.5% on PDAY medium. Unheated (27°C) conidia suspended in either water or oil and applied to tick cuticle developed appressoria 36h after treatment; whereas only heat-stressed conidia formulated in oil developed appressoria on tick cuticle. In comparison to conidia heated in mineral oil, there was a strong negative effect of heat on germination of conidia heated in water before being applied to arthropod cuticle. Nevertheless, bioassays [based primarily on egg production (quantity) and egg hatchability] exhibited high percentages of tick control regardless of the type of conidial suspension; i.e., water- or oil-formulated conidia, and whether or not conidia were previously exposed to heat. In comparison to aqueous conidial preparations, however, conidia formulated in oil reduced egg hatchability irrespective of heat or no-heat exposure. In conclusion, mineral-oil formulation protected conidia against heat-induced delay of both germination and appressorium production when applied to the cuticle of R. sanguineus.

Identification of Leishmania spp. promastigotes in the intestines, ovaries, and salivary glands of Rhipicephalus sanguineus actively infesting dogs.

Sand flies are recognized as the major vector of canine visceral leishmaniasis. However, in some areas of Brazil where sand flies do not occur, this disease is found in humans and dogs. There has been speculation that ticks might play a role in transmission of canine visceral leishmaniasis and the DNA of Leishmania spp. has been reported in whole ticks. We investigated the presence of Leishmania spp. promastigotes in the intestines, ovaries, and salivary glands of Rhipicephalus sanguineus ticks collected from tick-infested dogs in two cities of Brazil. We used 66 dogs that tested positive and 33 that tested negative for Leishmania spp. according to direct cytological examination assays. Ten ticks were collected from each dog and dissected to collect the intestines, ovaries, and salivary glands for immunohistochemistry (IHC) and diagnostic real-time polymerase chain reaction (RT-PCR). IHC results showed Leishmania spp. in 98, 14, and 8 % of the intestines, ovaries, and salivary glands, respectively. Real-time PCR showed that 89, 41, and 33 % of the tick intestine, ovary, and salivary glands, respectively, were positive for Leishmania spp. The verification of promastigotes of Leishmania spp. by two independent techniques in ticks collected from these urban region dogs showed that there is need for clarification of the role of ticks in the transmission of canine visceral leishmaniasis in Brazil.

Exposure of dogs to spotted fever group rickettsiae in urban sites associated with human rickettsioses in Costa Rica.

The zoonotic transmission cycles of Rickettsia rickettsii and other spotted fever group (SFG) rickettsiae in Latin America have usually been associated with rural or sylvatic environments, although domestic dogs can be implicated in more populated settings. In this study, exposure of dogs to SFG rickettsiae in the Greater Metropolitan Area of Costa Rica was investigated. Dogs from sites associated with human cases and from dog shelters were evaluated by indirect immunofluorescence assay (IFA) using antigen of SFG rickettsiae. Rickettsia spp. were detected in ectoparasites by polymerase chain reaction (PCR). A total 18.5% (31/168) of dogs associated with human cases and 6.8% (11/161) of dogs in shelters had IgG end titers≥64 to Rickettsia spp. The odds of being seropositive were greater in dogs from areas associated with human cases when compared to shelters (OR: 3.2; 95% C.I: 1.5-5.6). Rhipicephalus sanguineus sensu lato (s. l.) was present in all sites associated with human cases. Rickettsia felis URRWXCal2 and R. felis-like RF2125 were detected in Ctenocephalides felis, and Rickettsia sp. IbR/CRC in Ixodes boliviensis. Results demonstrate that dogs from the main urban center of Costa Rica have been exposed to SFG rickettsiae, especially in areas with known human infection. Both human and animal health sectors must be aware of possible rickettsial diseases in urban areas, where dogs may also serve as sentinels for human infection.

Ticks and fleas in crab-eating fox (Cerdocyon thous) of Pernambuco state, Brazil / Carrapatos e pulgas em cachorro-do-mato (Cerdocyon thous) do Estado de Pernambuco, Brasil

This study aimed to identify the species of fleas and ticks of Cerdocyon thous from the state of Pernambuco. Animals (n = 20) were examined, with 30% (6/20) ectoparasitized. Fleas (n = 16) and ticks (n = 17) parasitizing free-living crab-eating fox and captive in state of Pernambuco were collected. The fleas were identified as: Pulex irritans and Ctenocephalides felis; and the ticks were: Rhipicephalus sanguineus sensu lato and Amblyomma ovale. The presence of ectoparasites of domestic animals parasitizing C. thous, suggests a close contact of this species to the peridomicile. Furthermore, this is the first report of the occurrence of A. ovale in C. thous in northeastern Brazil.(AU)

Objetivou-se identificar as espécies de pulgas e carrapatos de Cerdocyon thous provenientes do estado Pernambuco. Foram examinados 20 animais, estando 30% (6/20) ectoparasitados. Foram coletadas 16 pulgas e 17 carrapatos em cachorros-do-mato de vida livre e de cativeiro no estado de Pernambuco. As pulgas foram identificadas como: Pulex irritans e Ctenocephalides felis; e os carrapatos foram: Rhipicephalus sanguineus sensu lato e Amblyomma ovale. A presença de ectoparasitos de animais domésticos parasitando C. thous, sugere a aproximação de indivíduos desta espécie ao peridomicílio. Além disso, este é o primeiro relato da ocorrência de A. ovale em C. thous no nordeste brasileiro.(AU)

Púrpura em cão Shih-Tzu com Trombocitopatia causada por Erliquiose canina: relato de caso / Purpura in a dog Shih-Tzu with thrombocytopathie caused by canine Ehrlichiosis: case report / Purpura en el perro Shih-Tzu com trombocitopatía causada por Ehrlichiosiscanina: report de un caso

A erliquiose é uma das doenças infecciosas mais importantes em nosso meio devido a ampla disseminação do seu vetor Rhipicephalus sanguineus, que transmite a Ricketsia Erlichia spp. A E. canis é o agente mais comum e o que causa a doença clínica mais grave. Um Shih-Tzu foi encaminhado para uma clínica particular com histórico de erliquiose com presença de lesões cutâneas. O exame físico evidenciou, na inspeção cutânea presença de petéquias e equimoses na região do abdômen juntamente com lesões hemorrágicas na região do dorso, com prurido discreto. Baseado nos sinais clínicos, achados hematológicos, e como exame complementar o PCR revelou-se positivo para E.canis no cão, o que foi compatível com diagnóstico de erliquiose associada a púrpura devido a trombocitopatia. A terapia medicamentosa com Prednisolona, Acetato de Hidrocortisona colaborou com a melhora das lesões dermatológicas, e o uso da Doxiciclina para E. canis resultou em uma efetiva melhora.

The ehrlichiosis is one of the most important infectious diseases in our country because of the wide spread of its vector Rhipicephalus sanguineus, which transmits the Ricketsia Ehrlichia spp. The E. canis is the most common agent and which causes the most severe clinical disease. A Shih-Tzu was referred to a private clinic with ehrlichiosis history with presence of skin lesions. Physical examination revealed in skin inspection presence of petechiae and bruises in the abdomen with hemorrhagic lesions in the dorsal region, with discreet pruritus. Based on clinical signs, haematological findings, to complement the PCR test was positive for E.canis the dog, which was compatible with a diagnosis of Ehrlichiosis associated with purpura due thrombocytopathie. Drug therapy with prednisolone, hydrocortisone acetate collaborated with the improvement of dermatological lesions, and the use of Doxycycline for E. canis resulted in an effective improvement.

La ehrlichiosis es una de las enfermedades infecciosas más importantes en nuestro país debido a la amplia difusión de su vector Rhipicephalus sanguineus, que transmite la Ricketsia Ehrlichia spp. La E. canis es el agente más común y la que causa la enfermedad clínica más severa. Un Shih-Tzu fue remitido a una clínica privada con la historia Ehrlichiosis con presencia de lesiones en la piel. El examen físico revela en la piel presencia inspección de petequias y hematomas en el abdomen con lesiones hemorrágicas en la región dorsal, com prurito discreto. Con base en los signos clínicos, hallazgos hematológicos, para complementar la prueba de PCR fue positivo para E. canis el perro, que era compatible con el diagnóstico de ehrlichiosis asociado com púrpura debido trombocitopatía. La terapia con medicamentos con prednisolona, acetato de hidrocortisona colaboró con la mejora de la lesiones dermatológicas, y el uso de doxiciclina para E. canis resultó en una mejora efectiva.

Ticks and fleas in crab-eating fox (Cerdocyon thous) of Pernambuco state, Brazil / Carrapatos e pulgas em cachorro-do-mato (Cerdocyon thous) do Estado de Pernambuco, Brasil

This study aimed to identify the species of fleas and ticks of Cerdocyon thous from the state of Pernambuco. Animals (n = 20) were examined, with 30% (6/20) ectoparasitized. Fleas (n = 16) and ticks (n = 17) parasitizing free-living crab-eating fox and captive in state of Pernambuco were collected. The fleas were identified as: Pulex irritans and Ctenocephalides felis; and the ticks were: Rhipicephalus sanguineus sensu lato and Amblyomma ovale. The presence of ectoparasites of domestic animals parasitizing C. thous, suggests a close contact of this species to the peridomicile. Furthermore, this is the first report of the occurrence of A. ovalein C. thous in northeastern Brazil.(AU)

Objetivou-se identificar as espécies de pulgas e carrapatos de Cerdocyon thous provenientes do estado Pernambuco. Foram examinados 20 animais, estando 30% (6/20) ectoparasitados. Foram coletadas 16 pulgas e 17 carrapatos em cachorros-do-mato de vida livre e de cativeiro no estado de Pernambuco. As pulgas foram identificadas como: Pulex irritans e Ctenocephalides felis; e os carrapatos foram: Rhipicephalus sanguineus sensu lato e Amblyomma ovale. A presença de ectoparasitos de animais domésticos parasitando C. thous, sugere a aproximação de indivíduos desta espécie ao peridomicílio. Além disso, este é o primeiro relato da ocorrência de A. ovaleem C. thous no nordeste brasileiro.(AU)