Ctenocephalides Research Articles

Ctenocephalides orientis and Ctenocephalides felis in Thailand: Head geometry by species, sex and geography.

Fleas in the genus Ctenocephalides serve as biological vectors or intermediate hosts of microorganisms such as bacteria, rickettsia, protozoa and helminths. Ctenocephalides felis has a worldwide distribution, while C. orientis has long been considered as a subspecies of C. felis in Asia. To help the morphological recognition of these two species and further explore their differences, we used the geometric morphometric approach applied to the head. Both sexes were examined. Five anatomical landmarks of the head were used, and to capture the curvature of the front head, 10 semilandmarks were added. There was a consistent difference in species classification accuracy when considering landmarks only versus their combination with semilandmarks, suggesting the importance of the curve of the head as a taxonomic signal. Using or not the labels in the reclassification analyses, the head shape allowed by itself almost perfect recognition of the two species, in both sexes, even after adjustment for prior probabilities. The same approach disclosed a high level of sexual size and shape dimorphism in both species. The contribution of size variation to the discrimination by shape was much more important between sexes (from 27% to 45%) than between species (from 0.7% to 7.1%). Nevertheless, in our data, size never could represent a way to reliably recognise the sex of an individual, even less its species. Geographical variation in head shape could only be explored for the C. orientis sample. No significant correlation of morphometric variation with geography could be detected, which would be consistent with gene flow between Thai provinces. The geometric morphometric approach of the flea head, when it incorporates head curves, is a promising tool for rapid, economical, and accurate species and sex identification. It is, therefore, a useful tool for future epidemiological and demographic studies.

Potential ectoparasiticide for dog and cat fleas, a combination of Ficus minahassae extract and latex from Carica papaya L.

This study aimed to analyze the compound content of the combined extracts of Langusei fruit (Ficus minahassae L.) and papaya latex (Carica papaya L.) and perform bioassays of the combination of extracts on fleas of the genus Ctenocephalides. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) determined the chemical composition of the combined extract. The toxicity of the extract combination was evaluated in vivo on cat flea and dog flea imago separately. The combination of phytochemical screening of Langusei extract and papaya latex contained all the main phytochemical compounds. The LCMS/MS analysis results showed that the combination of Langusei extract and papaya latex contained six compounds. Four compounds were identified: 3-butenyl glucosinolate, erythromycin, aluminum palmitate, and henpentakontilbenzene. Four compounds indicate a new compound. The toxicity of the combined extract was highest for both Ctenocephalides felis and Ctenocephalides canis in the P4 treatment (10%), with an average mortality of 100%, the same as the control mortality of the synthetic insecticide deltamethrin. The best LD50 for C. felis was in the F1 formula (4.003 mg/l), while in C. canis it was shown in the F3 (3.733 mg/l). Based on the results obtained, the combination of Langusei fruit extract and papaya latex can be developed as an ectoparasiticide for fleas of the genus Ctenocephalides.

Seasonality and other risk factors for fleas infestations in domestic dogs and cats.

Fleas in the genus Ctenocephalides are the most clinically important parasitic arthropods of dogs and cats worldwide yet risk factors that might increase the risk of infestation in small animals remains unclear. Here we developed a supervised text mining approach analysing key aspects of flea epidemiology using electronic health records from domestic cats and dogs seen at a sentinel network of 191 voluntary veterinary practices across Great Britain between March 2014 and July 2020. Our methods identified fleas as likely to have been present during 22,276 of 1,902,016 cat consultations (1.17%) and 12,168 of 4,844,850 dog consultations (0.25%). Multivariable logistic regression modelling found that animals originating from areas of least deprivation were associated with 50% reductions in odds of veterinary-recorded flea infestation compared to the most deprived regions in England. Age of the animal was significantly associated with flea presentation in both cats and dogs, with cases peaking before animals reached 12 months. Cases were recorded through each study years, peaking between July and October, with fluctuations between each year. Our findings can be used towards healthcare messaging for veterinary practitioners and owners.

Factors associated with endoparasites and ectoparasites in domiciled dogs in the metropolitan area of Toluca, México

ResumenIntroducción. Los endoparásitos y ectoparásitos en perros son de distribución mundial. La estrecha relación entre los perros y el hombre implica un riesgo de transmisión de parasitosis zoonóticas, por lo cual es necesario conocer las especies que parasitan a los perros de esta zona y determinar los factores asociados.Objetivos. Estimar la prevalencia de endoparásitos y ectoparásitos, identificarlos en perros domiciliados de la zona metropolitana de Toluca, México, y determinar la prevalencia de Dipyilidium caninum en pulgas del género Ctenocephalides spp.Materiales y métodos. Se recolectaron muestras de 402 perros que fueron llevados a consulta en cuatro hospitales de referencia de Toluca. En el diagnóstico de endoparásitos, se utilizaron las técnicas coproparasitoscópicas de frotis directo, flotación y sedimentación; además, se recolectaron ectoparásitos para su identificación taxonómica. Por último, la detección de D. caninum en pulgas se hizo mediante la reacción en cadena de la polimerasa (PCR).Resultados. El 37,2 % de los perros resultó positivo para endoparásitos. Los géneros o especies identificados fueron Toxocara spp., Giardia spp., Ancylostoma spp., Cystoisospora spp., D. caninum, Taenia spp. y Trichuris vulpis. Se determinó una prevalencia de ectoparásitos de 13,13 %. Se identificaron pulgas de las especies Ctenocephalides felis y C. canis, en tanto que solo un animal presentó parasitosis por Rhipicephalus sanguineus y otro por Trichodectes canis. La prevalencia de D. caninum en pulgas fue del 9,5 %. Conclusión. La prevalencia de endoparásitos fue de 37,2 % y, la de ectoparásitos, de 13,1 %. Por primera vez en México se hizo un análisis de endoparásitos y ectoparásitos en una misma población de perros, así como el diagnóstico molecular de D. caninum.

Differential characters of fleas of the genus Ctenocephalides (Siphonaptera, Pulicidae) obtained from dogs

Fleas are the common name of the order Siphonaptera, obligate provisional nidiculous parasites of mammals and, to a lesser extent, birds, which can also feed on humans. Fleas can cause ctenocephalidosis of dogs and are carriers of many dangerous infectious and invasive diseases. Their ability to use humans as an alternative host determines the importance of these parasites in health care. Therefore, the aim of the work was to establish morphological and metric characters of adult male and female fleas of the species Ctenocephalides felis Bouche, 1835 and C. canis Curtis, 1826, isolated from domestic dogs for species identification. Morphological studies of fleas have shown that the differential features of C. felis and C. canis include the shape of the head and anterior-dorsal cuticular notch on the head. Notably, male fleas of both species have a more rounded forehead than female fleas. The metric parameters of adult fleas can be used as additional identification features, which will increase the efficiency of differential diagnosis of parasitic insects. We found differences in male fleas by 23 parameters, of which the value of 17 parameters were smaller in C. canis specimens. Males of C. felis were 9.1–21.1% larger in total body length, lengths of head and thorax, as well as lengths of mesothorax and metathorax. Differential features included size of the teeth of the main ctenidium and pronotal ctenidium: in C. felis males all eight teeth of the main ctenidium, located on the left side, were longer by 12.7–41.7%, and the first, seventh, eighth teeth were wider by 25.4–43.0% than in C. canis. In female fleas, differences were found for 24 metric parameters, of which the values of 20 parameters were also smaller in C. canis specimens. Females of C. felis were 12.1–22.2% larger in terms of total body length, head, breast, prothorax, mesothorax, and metathorax. All their teeth of the main ctenidium were longer by 5.6–40.6%, and the first, second, third, and eighth teeth were 18.1–48.9% wider than in females of C. canis. The obtained results add to the already existing data on morphometric features of adult fleas of C. felis and C. canis species, and will allow timely and accurate diagnosis of ctenocephalidosis in dogs caused by parasites of these species.

Ectoparasites Ctenocephalides (Siphonaptera, Pulicidae) in the Composition of Mixed Infestations in Domestic Dogs from Poltava, Ukraine

Abstract One of the most common ectoparasites on domestic carnivores are fleas from the genus Ctenocephalides. This group of blood sucking insects are one of the most important in medical and veterinary terms, as they can serve as carriers of dangerous infectious and may cause other invasive diseases. Research studies have established a variety of fleas and other contagions parasitizing domestic dogs in Poltava, Ukraine. Certain peculiarities of these ectoparasitic studies, as a part of mixed infestations of dogs, have recently been determined. The results of the studies have shown that the species composition of the fleas was represented by two main species. The dominant species was Ct. felis, and their prevalence was 36.05 %. Another species (Ct. canis) was diagnosed less often and had a prevalence of 27.94 %. It was found that in 31.18 % of the dogs, the blood-sucking insects were mostly parasitizing in the form of an associations with: nematoda (Toxocara canis, Trichuris vulpis, Uncinaria stenocephala), Cestoda (Dipylidium caninum), protozoa (Cystoisospora canis), and another ectoparasite (Trichodectes canis). Overall, 33 types of mixed infestations were detected. Moreover, the number of different parasitic species in each dog ranged from one to seven. Fleas of the genus Ctenocephalides (in the composition of two species of parasites) were registered the most often (14.60 %). The infestation of dogs with other forms of mixed infestations was 0.69—8.01 %. The most frequent co-members for Ct. felis were Cestoda [D. caninum (13.47 %)], for Ct. canis—Cestoda [D. caninum (11.23 %)] and Nematoda [T. vulpis (8.29 %)].

Age dynamics of infestation of dogs Ctenocephalides spp.

The ectoparasites Ctenocephalides felis and Ctenocephalides canis are distributed worldwide and are the most common species of fleas that parasitize domestic carnivores. As active vectors of infectious and invasive diseases, fleas of the genus Ctenocephalides are of great epidemiological importance. Intensive growth of the number of dogs, violation of sanitary and hygienic conditions of their keeping, especially in large cities, as well as global warming significantly affect the epizootic situation regarding ctenocephalidosis. The aim of the work was to study the features of age susceptibility of domestic dogs in the city of Poltava (Ukraine) to Ctenocephalides spp. Indicators of infestation of animals with the causative agent of ctenocephalidosis depending on their age and housing conditions were determined. Studies have shown that dogs of any age are prone to flea infestation. Ctenocephalidosis is diagnosed in animals of all ages. At the same time, the age dynamics of defeat of dogs by parasitic insects under different conditions of their keeping differed significantly. The average extensity and intensity of the invasion was lower in animals kept in apartments (26.47 %, 10.82 specimens/head) compared to animals kept in the private sector (76.21 %, 22.71 specimens/head). The highest rates of flea infestation of the genus Ctenocephalides were found in dogs aged one to six years (37.10–45.45 %; 10.45–15.91 specimens/head) – for housing, as well as in young animals up to 12 month of age (84.03–90.36 %; 22.78–32.56 specimens/head) – for aviary maintenance. Less infested were dogs under 6 months of age (11.26 %; 5.43 specimens/head) and older 6-year-olds (16.28 %; 8.54 specimens/head) – for housing, as well as dogs aged one to six years (53.54–75.38 %; 11.63–20.24 specimens/head) – for aviary keeping. The results obtained regarding the age dynamics of infestation of domestic dogs with fleas of the genus Ctenocephalides can be taken into account when carrying out measures to control and prevent ctenocephalidosis in dogs under different conditions of their content.

Biochemical parameters of blood serum of dogs for ctenocephalidosis

One of the most common ectoparasitic diseases of domestic carnivorous animals is ctenocephalidosis caused by fleas of the genus Ctenocephalides. The peculiarity of this invasion is a chronic course associated with the constant attack of parasitic insects on the animal, accompanied by severe itching, the occurrence of alopecia, the development of eczema, dermatitis and the subsequent introduction of pathogenic microflora into the damaged tissue. The aim of the study was to investigate the effect of fleas of the genus Ctenocephalides on the biochemical parameters of the blood serum of invaded dogs. Three groups of animals were formed: a control (clinically healthy dog) and two experimental animals (infected by the parasitic insect Ctenocephalides spp.) with different intrusion rates. In blood serum determined: the content of total protein, albumin, total bilirubin, creatinine, urea, glucose, cholesterol, phosphorus, potassium, calcium, magnesium, alanine aminotransferase activity, aspartate aminotransferase, alkaline phosphate. Conducted studies found that rates the intensity of infestation significantly influence the changes that occur in blood serum infested dogs. The intensity of ctenocephalidosic infestation of up to 15 specimens of fleas in the animal in their blood serum showed a significant decrease in albumin content (by 22.37 %) compared to that in clinically healthy dogs. The intensities of xenophalphalous infestation of 16–47 specimens of fleas per animal in the serum of the infected animals showed a significant decrease in albumin (by 29.28 %), glucose (by 25.29 %), and cholesterol (by 35.59 %) relative to similar indicators clinically healthy animals. At the same time in the serum of the infested dogs the content of total bilirubin (by 15.73 %), as well as the activity of alanine aminotransferase (1.4 times), aspartate aminotransferase (1.4 times) and alkaline phosphatase (2 times). The results of the experimental data extend the already existing data on the pathogenesis of fleas parasites in dogs, and will also allow the effective treatment of diseased animals.

Survey of Bartonella species in cats from Abruzzo region, Italy.

Cat scratch disease (CSD) is a zoonotic disease, caused predominantly by Bartonella henselae and transmitted to humans through a scratch or bite of the cat. Cat represents the principal reservoir and healthy carrier of Bartonella, which is mainly transmitted, among cats, by the flea Ctenocephalides felis. During 2014, fifty‑two samples of whole blood and sera were collected randomly from cats in Abruzzo region and were examined by real-time PCR and IFAT tests, respectively. Seven samples out of fifty‑two (13.5%) resulted positive for Bartonella spp. in both tests, while six specimens (11.5%) resulted real-time PCR negative but IgG positive; thirty‑nine were instead both real-time PCR and IFAT negative (75%). Sequence analysis of a fragment of DNA identified B. henselae and B. clarridgeiae in four and in two real‑time PCR positive samples, respectively.

Эпизоотологические особенности ктеноцефалидозов кошек в Ульяновске

Эпизоотологические особенности ктеноцефалидозов кошек в Ульяновске

Controle e prevenção de pulgas em cães e gatos: análise das ações dos tutores

As pulgas são insetos achatados lateralmente, sem asas, pertencentes ao Filo Arthropoda, à classe Insecta e à ordem Siphonaptera. Na medicina veterinária, as pulgas são habitualmente encontradas em cães e gatos, porém, elas também vivem em uma variedade de outros animais domésticos e pequenos selvagens. A subespécie predominante que parasita cães e gatos é a Ctenocephalides felis felis, conhecida como pulga do gato, causando no animal ação irritativa e inflamatória, além de transmitir patógenos, onde estas causam perturbação e estresse aos animais, provocados pelas suas picadas e movimentos. A pesquisa foi realizada com tutores de animais de estimação, residentes em duas avenidas do Setor Pestana, em Guaraí Tocantins. A coleta de dados foi realizada através de questionários aplicados a todos os tutores de animais e continha seis perguntas fechadas de múltiplas escolhas. Acerca do questionário sobre o método de prevenção e controle de pulgas nos animais, foi constatado que 54% dos responsáveis utilizam medicamentos oriundos de farmácias. Com isso, conclui-se que prevalece o número de donos de animais que tem consciência dos danos a saúde que as pulgas podem causar a seus animais bem como o impacto econômico.

Out-of-Africa, human-mediated dispersal of the common cat flea, Ctenocephalides felis: The hitchhiker’s guide to world domination

The cat flea (Ctenocephalides felis) is the most common parasite of domestic cats and dogs worldwide. Due to the morphological ambiguity of C. felis and a lack of — particularly largescale — phylogenetic data, we do not know whether global C. felis populations are morphologically and genetically conserved, or whether human-mediated migration of domestic cats and dogs has resulted in homogenous global populations. To determine the ancestral origin of the species and to understand the level of global pervasion of the cat flea and related taxa, our study aimed to document the distribution and phylogenetic relationships of Ctenocephalides fleas found on cats and dogs worldwide. We investigated the potential drivers behind the establishment of regional cat flea populations using a global collection of fleas from cats and dogs across six continents. We morphologically and molecularly evaluated six out of the 14 known taxa comprising genus Ctenocephalides, including the four original C. felis subspecies (Ctenocephalides felis felis, Ctenocephalides felis strongylus, Ctenocephalides felis orientis and Ctenocephalides felis damarensis), the cosmopolitan species Ctenocephalides canis and the African species Ctenocephalides connatus. We confirm the ubiquity of the cat flea, representing 85% of all fleas collected (4357/5123). Using a multigene approach combining two mitochondrial (cox1 and cox2) and two nuclear (Histone H3 and EF-1α) gene markers, as well as a cox1 survey of 516 fleas across 56 countries, we demonstrate out-of-Africa origins for the genus Ctenocephalides and high levels of genetic diversity within C. felis. We define four bioclimatically limited C. felis clusters (Temperate, Tropical I, Tropical II and African) using maximum entropy modelling. This study defines the global distribution, African origin and phylogenetic relationships of global Ctenocephalides fleas, whilst resolving the taxonomy of the C. felis subspecies and related taxa. We show that humans have inadvertently precipitated the expansion of C. felis throughout the world, promoting diverse population structure and bioclimatic plasticity. By demonstrating the link between the global cat flea communities and their affinity for specific bioclimatic niches, we reveal the drivers behind the establishment and success of the cat flea as a global parasite.

Parasitic affections of domesticated pigeons (Columba livia) in Jammu, India

The parasitic fauna of domesticated pigeons in Jammu region were not recorded and so a survey was undertaken amongst a population of approximately 4000 birds in twelve areas around Jammu. Ectoparasites and haemoprotozoa from live birds, and endoparasites from dead birds were recorded. Ova shed in feces were also screened in four different seasons. Ectoparasites recovered include Columbicola columbae, Campanulotes bidentatus, Pseudolynchia canariensis, Ctenocephalides sp., Psoroptes sp. A total of 22 (36.67%) out 60 gastrointestinal tracts (GIT) of pigeons were positive for helminthic endoparasites including Raillietina sp. (25%; 15/60); Ascaridia sp. (5%; 3/60) and the hairworm Capillaria sp. (6.67%; 4/60). coccidian (58.3%; 35/60), cryptosporidian parasites (50.0%; 5/10), Trichomonas gallinae (40%; 12/30) and haemoprotozoal schizogony tissue stages (45.0%; 27/60) were observed in cloacal, oro-pharyngeal and tissue samples from post-mortem materials. Prevalence of cestodes was relatively more than nematodes perhaps due to the pigeon’s access to intermediate hosts of the cestodes. Blood smears showed the presence of Haemoproteus columbae gametocytes (26.6%; 8/30). Twenty-four pooled fecal samples examined from six select villages revealed presence of different parasitic ova. A higher prevalence of parasitic eggs was noted in the winters. Ascarid eggs were particularly prevalent during monsoon and post monsoon. Raillietina sp. was the most common cestode with lowered prevalence in the peak summers. It is speculated that close confinement of the domesticated birds are responsible for increased parasitic load and their dissemination. The parasitic data generated in the study may be helpful in estimating the faunistic prevalence of different parasites for strategic management of such parasitism during various seasons.

Ctenocephalides felis and Ctenocephalides canis: introgressive hybridization?

AbstractIn the present work, a comparative molecular study of Ctenocephalides felis and Ctenocephalides canis isolated from dogs (Canis lupus familiaris) from different geographical regions (Spain, Iran and South Africa) was carried out. We found morphological variations in C. felis that do not correspond with molecular differences. The Internal Transcribed Spacers 1 and 2 (ITS1, ITS2) and 18S rRNA partial gene, and cytochrome c‐oxidase 1 (cox1) mtDNA partial gene sequences were determined to clarify the taxonomic status of these two species, and to assess interpopulation variation and interspecific sequence differences. In addition, a comparative phylogenetic study with other species of fleas using Bayesian, Maximum Parsimony and Maximum Likelihood analysis was performed. The 18S rRNA partial gene fragment was useful neither to discriminate C. canis and C. felis nor to infer phylogenetic relationships at this level, whereas ITS1 and ITS2 assessed for specific determination in the genus Ctenocephalides. The cox1 mtDNA sequences of C. felis revealed three main haplotypes and we suggest that there has been introgression of C. canis cox1 mtDNA into C. felis by Wolbachia pipientis. Based on cox1 sequences, restriction mapping identified many endonucleases that could be used to delineate different haplotypes of C. felis and to differentiate C. felis and C. canis.

Parasites of sheep herding dogs in central Germany.

This paper reports on endoparasite infections diagnosed in 2012 by standard coproscopical techniques and coproantigen Giardia ELISA in 165 dogs used for sheep herding in 36 farms in central Germany. The overall prevalence of dogs with evidence of endoparasite infections was 27.3% (95% CI 20.6-34.7). The most frequently identified faecal forms were those of ascarids (Toxocara, 6.7%; Toxascaris 3.6%), hookworms (5.5%) and taeniid cestodes (4.2%), followed by those of Trichuris whipworms (3.0%), Capillaria aerophila (1.8%), Angiostrongylus and Crenosoma lungworms (1.2% each) and Cystoisospora canis coccidians (0.6%). Molecular identification demonstrated the seven dogs shedding taeniid eggs positive for Taenia (T.) species tapeworms (five, T. hydatigena; one, T. ovis; one Taenia sp.). Screening of the faeces with the coproantigen ELISA revealed Giardia specific antigen in 5.5% of the samples. The majority of the dogs had evidence of single endoparasite infections (22.4%) while evidence for infection with two or three parasites concurrently was found in six (3.6%) and two (1.2%) of the dogs, respectively. Dogs ≤ 1 year (n = 19) were parasitized more frequently (p < 0.05) with overall gastrointestinal parasites (63.2% vs. 20.5%), ascarids (36.8% vs. 6.8%) and Giardia spp. (21.1% vs. 3.4%) than older dogs (n = 146). Dogs which had been wormed within six months of examination tested less frequently positive for gastrointestinal helminths compared to dogs not wormed (11.1% vs. 25.0%; p = 0.0567). In addition, ear swabs taken from 43 sheep dogs in 2012 were examined, and Otodectes cynotis mites were extracted from one dog. Identification of ectoparasites collected by full body search and combing from 113 sheep dogs in the years 2011 to 2013 revealed infestation of fleas and ticks (each up to five specimens per dog) on 13 and 108 dogs, respectively, with nine dogs carrying both fleas and ticks. Archaeopsylla erinacei, Ctenocephalides (C) canis, C. felis and Pulex irritans fleas were identified from one, three, two and eleven dogs, respectively. Dermacentor reticulatus, Ixodes (I.) hexagonus and I. ricinus ticks were isolated from 16, eight and 95 dogs, respectively.

Integrated morphological and molecular identification of cat fleas (Ctenocephalides felis) and dog fleas (Ctenocephalides canis) vectoring Rickettsia felis in central Europe

Fleas of the genus Ctenocephalides are the most common ectoparasites infesting dogs and cats world-wide. The species Ctenocephalides felis and Ctenocephalides canis are competent vectors for zoonotic pathogens such as Rickettsia felis and Bartonella spp. Improved knowledge on the diversity and phylogenetics of fleas is important for understanding flea-borne pathogen transmission cycles. Fleas infesting privately owned dogs and cats from the Czech Republic (n=97) and Romania (n=66) were subjected to morphological and molecular identification and phylogenetic analysis. There were a total of 59 (60.82%) cat fleas (Ctenocephalides felis felis), 30 (30.93%) dog fleas (Ctenocephalides canis), 7 (7.22%) European chicken fleas (Ceratophyllus gallinae) and 1 (1.03%) northern rat flea (Nosopsyllus fasciatus) collected in the Czech Republic. Both C. canis and C. felis felis were identified in Romania. Mitochondrial DNA sequencing at the cox1 gene on a cohort of 40 fleas revealed the cosmopolitan C. felis felis clade represented by cox1 haplotype 1 is present in the Czech Republic. A new C. felis felis clade from both the Czech Republic and Romania is also reported. A high proportion of C. canis was observed from dogs and cats in the current study and phylogeny revealed that C. canis forms a sister clade to the oriental cat flea Ctenocephalides orientis (syn. C. felis orientis). Out of 33 fleas tested, representing C. felis felis, C. canis and Ce. gallinae, 7 (21.2%) were positive for R. felis using diagnostic real-time PCR targeting the gltA gene and a conventional PCR targeting the ompB gene. No samples tested positive for Bartonella spp. using a diagnostic real-time PCR assay targeting ssrA gene. This study confirms high genetic diversity of C. felis felis globally and serves as a foundation to understand the implication for zoonotic disease carriage and transmission by the flea genus Ctenocephalides.

Evidence for a specific host-endosymbiont relationship between 'Rickettsia sp. genotype RF2125' and Ctenocephalides felis orientis infesting dogs in India.

BackgroundFleas of the genus Ctenocephalides serve as vectors for a number of rickettsial zoonoses, including Rickettsia felis. There are currently no published reports of the presence and distribution of R. felis in India, however, the ubiquitous distribution of its vector Ctenocephalides felis, makes it possible that the pathogen is endemic to the region. This study investigates the occurrence of Rickettsia spp. infection in various subspecies of C. felis infesting dogs from urban areas of Mumbai, Delhi and Rajasthan in India.MethodsIndividual fleas collected off 77 stray dogs from Mumbai, Delhi and Rajasthan were screened for Rickettsia spp. by a conventional PCR targeting the ompB gene. Further genetic characterisation of Rickettsia-positive fleas was carried out using nested PCR and phylogenetic analysis of partial DNA sequences of the gltA and ompA genes. Ctenocephalides spp. were morphologically and genetically identified by PCR targeting a fragment of cox1 gene.ResultsOverall, 56/77 fleas (72.7%), including 22/24 (91.7%) from Delhi, 32/44 (72.7%) from Mumbai and 2/9 (22.2%) from Rajasthan were positive for Rickettsia DNA at the ompB gene. Sequences of gltA fragments confirmed the amplification of Rickettsia sp. genotype RF2125. The ompA gene of Rickettsia sp. genotype RF2125 was characterised for the first time and shown 96% identical to R. felis. Three species of Ctenocephalides were identified, with the Ctenocephalides felis orientis being the dominant flea species (69/77; 89.6%) in India, followed by Ctenocephalides felis felis (8/77; 10.4%).ConclusionsHigh occurrence of Rickettsia sp. genotype RF2125 in C. felis orientis and the absence of R. felis suggests a specific vector-endosymbiont adaptation and coevolution of the Rickettsia felis-like sp. within subspecies of C. felis.

The survey of rat density and flea index in households in villages having previous plague experience in Lianghe County, Yunnan Province in 2007

Objective To evaluate the risk of plague occurrence via surveying and analyzing indoor rat density and flea index in natural villages having previous plague experience. Methods During August to September 2007, 30 natural villages experiencing previous plague were selected based on the surveillance data, and then all households were coded with numbers and 20 households in each village were randomly selected via computer. Cages and sticky papers were set in 600 selected households to capture rats and fleas. Rat density, flea prevalence, flea index and median were estimated. Results One hundred thirty-three Rattus flavipectus and 33 Suncus murinus were caught and averaged rat density was 2.8 rats per one hundred cage. nights (166/6000), the median was 5 rats each village. One hundred and one mice infected fleas, flea prevalence on rats was 60.8% (101/166), 296 Xenopsylla cheopis and 48 Leptopsylla segnis were collected. Rat flea index was 2.1 fleas per rat (344/166). A total of 315 dissociated flea was caught, average dissociated flea index was 0.026 fleas per sticky paper (315/11888). The median was 5.5 dissociated fleas per village. Of dissociated fleas, Ctenocephalides felis felis (205) and Xenopsylla cheopis (103) accounted for 97.8% (308/315). The proportion for species of the rat flea and the dissociated flea was different(Fisher test: P < 0.01). The rat flea was significantly associated with the rat density(r = 0.68, P < 0.01), but the dissociated flea was significantly associated with neither the rat density(r = -yield than fried wheat batter(χ2 = 5.59, P < 0.05). Conclusions In these villages having previous plague experience of Lianghe County, Rattusflavipectus was dominant species of indoor rats, Xenopsylla cheopis and Ctenocephalides felis felis were dominant species of rat flea and dissociated flea, respectively. Mengsong, Bangdu, and Tangjiatun village had potential risk of plague emergence. Key words: Plague; Rat density ; Flea index; Dissociated flea; Rat bait

MORPHOLOGIC STUDY OF DOG FLEA SPECIES BY SCANNING ELECTRON MICROSCOPY

Fleas are wingless insects with laterally compressed body of about 1, 5- 4 mm length. Like all insects they possess six legs and three body segments (Kramer and Mencke, 2001). Taxonomically they belong to: Phylum Arthropoda, Class: Insecta Order Siphonaptera. The most frequent flea species occurring in dogs are worldwide represented by species from Pulicidae family, including Ctenocephalides spp. (Hopkins and Rothschild, 1953). The purpose of this study was to make a detailed morphologic study of the two most frequent flea species from the dog, Ctenocephalides canis and Ctenocephalides felis, by scanning electron microscopy.

THE DIAGNOSTIC VALUE OF THE ARTUVETRIN INTRADERMAL SKIN TEST SET IN THE DIFFERENTIAL DIAGNOSIS OF THE ALLERGIC DOG SKIN DISEASES

The allergic dog skin diseases differential diagnosis in most part of Transylvania is based on history, clinical examination and therapeutically results. In this study the Artuvetrin intra dermal skin tests (IDT) were used to investigate whether a dog is allergic to specific allergens such as grass pollen, tree pollen, mites, insects. A number of 27 dogs with different skin lesions were tested with 16 specific Artuvetrin dog allergens. The majority of dogs had immediate positive skin reactions, with appearance of a wheal and nodule at the injection side, to the dust mite (Dermatophagoides farinae)(18 cases), followed by a positive reactivity to the Ctenocephalides spp. extract (15 cases), the Tyrophagus putrescentiae and Acarus siro (3 cases). Delayed reactions were described just in 3 cases. 66, 66% of dog with a positive dust mite reaction had an indoor habitat. So using Artuvetrin skin test set all the 27 dogs were diagnosed with one of the three most frequent allergic skin diseases. In conclusion, the dog allergic dermatitis differential diagnosis can based on corroboration of history's findings, clinical examinations and the result of Artuvetrin set IDT