ABSTRACT
In order to investigate the prevalence and life cycle of apicomplexan parasites, small mammals were live-trapped with modified Sherman traps in Southern Hungary between 2010 and 2012. Altogether, 528 rodents (Apodemus flavicollis Melchior, 1834, Apodemus agrarius Pallas, 1771, Myodes glareolus Schreber, 1780, Microtus agrestis Linnaeus, 1761, Mus musculus Linnaeus, 1758 and Micromys minutus Pallas, 1771) were collected and four shrews (Sorex spp.) were by-catched. Captured animals belonging to non-protected species were euthanized, and spleen samples were preserved for histological and molecular analyses. During the examination of spleen smears, Hepatozoon parasites were observed in eight out of 48 bank voles (M. glareolus). DNA was isolated from altogether 221 spleen samples, and 18S rDNA was amplified using two different PCR protocols. The eight bank vole samples were positive with PCR, but none of the other M. glareolus spleen samples or any of the tissue samples from other species were found to be infected. Sequenced amplicons were very similar to Hepatozoon spp. detected in M. glareolus in Spain and Poland. Ectoparasites were collected from the small mammal carcasses and from the vegetation. Hepatozoon DNA was not found in the 181 ticks removed from the small mammals or in the 162 ticks collected with flagging, but was detected in all three flea species (4/43 Megabothris turbidus Rothschild, 1909, 3/10 Ctenophthalmus assimilis Taschenberg, 1880 and 7/78 Ctenophthalmus agyrtes Heller, 1896). Based on gamont morphology, vertebrate and arthropod host species and DNA sequences, the parasites in our study can be identified as Hepatozoon erhardovae.
Subject(s)
Arvicolinae/parasitology , Eucoccidiida/classification , Eucoccidiida/isolation & purification , Shrews/parasitology , Siphonaptera/parasitology , Ticks/parasitology , Animals , Eucoccidiida/genetics , Flea Infestations , Hungary , Life Cycle Stages , Poland , Polymerase Chain Reaction , RNA, Ribosomal, 18S/genetics , SpainABSTRACT
BACKGROUND: In the family Trypanosomatidae, the genus Trypanosoma contains protozoan parasites that infect a diverse range of hosts, including humans, domestic animals, and wildlife. Wild rodents, as natural reservoir hosts of various pathogens, play an important role in the evolution and emergence of Trypanosomatidae. To date, no reports are available on the trypanosomatid infection of pikas (Lagomorpha: Ochotonidae). METHODS: In this study, Mongolian pikas and their fleas were sampled at the China-Mongolia border, northwestern China. The samples were analyzed with polymerase chain reaction (PCR) and sequencing for the presence of Trypanosomatidae on the basis of both the 18S ribosomal RNA (18S rRNA) gene and the glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) gene. The morphology of trypomastigotes was also observed in peripheral blood smears by microscopy. RESULTS: Molecular and phylogenetic analyses revealed a new genotype of the Trypanosoma lewisi clade that was found both in pika blood and flea samples. This genotype, which probably represents a new species, was provisionally designated as "Trypanosoma sp. pika". In addition, a novel genotype belonging to the genus Blechomonas of Trypanosomatidae was detected in fleas. On the basis of its molecular and phylogenetic properties, this genotype was named Blechomonas luni-like, because it was shown to be the closest related to B. luni compared with other flea-associated trypanosomatids. CONCLUSIONS: To the best of our knowledge, this is the first study to report any trypanosomatid species in Mongolian pikas and their fleas. Further studies are needed to investigate the epidemiology of these protozoan parasites, as well as to evaluate their pathogenicity for humans or domestic animals.
Subject(s)
Lagomorpha , Siphonaptera , Trypanosoma , Trypanosomatina , Animals , Humans , Lagomorpha/parasitology , Siphonaptera/parasitology , Phylogeny , China/epidemiology , Trypanosoma/genetics , Trypanosomatina/genetics , Animals, Domestic , GerbillinaeABSTRACT
For many pathogens with environmental stages, or those carried by vectors or intermediate hosts, disease transmission is strongly influenced by pathogen, host, and vector movements across complex landscapes, and thus quantitative measures of movement rate and direction can reveal new opportunities for disease management and intervention. Genetic assignment methods are a set of powerful statistical approaches useful for establishing population membership of individuals. Recent theoretical improvements allow these techniques to be used to cost-effectively estimate the magnitude and direction of key movements in infectious disease systems, revealing important ecological and environmental features that facilitate or limit transmission. Here, we review the theory, statistical framework, and molecular markers that underlie assignment methods, and we critically examine recent applications of assignment tests in infectious disease epidemiology. Research directions that capitalize on use of the techniques are discussed, focusing on key parameters needing study for improved understanding of patterns of disease.
Subject(s)
Communicable Diseases/transmission , Disease Vectors , Host-Parasite Interactions/genetics , Administration, Oral , Animal Migration , Animals , Chagas Disease/prevention & control , Coccidioidomycosis/genetics , Coccidioidomycosis/prevention & control , Genetics, Population , Geography , Humans , Insecticides , Rabies Vaccines/administration & dosage , Raccoons/parasitology , Sciuridae/parasitology , Siphonaptera/parasitology , Triatoma , Yersinia pestis/geneticsABSTRACT
Laboratory studies of fleas for gregarines have established that it is the latter inhabiting the intestine and stomach of the fleas of wild rodents which are of much interest as protozoa, in whose organism, parasitic species of bacteria can survive. Penetration of plague bacteria into the endoplasm ofgregarines and their possible survival in the cysts may create an additional component in the chain of an epizootic process, which ensures its function, without involving the rodents at the nesting biocenotic level following the pattern: flea imagoes - nesting litter infected with gregarine spores, cysts - flea larvae - flea imagoes infected with cysts, with the plague pathogen emerging into a rodent population through the imago of blocked fleas.
Subject(s)
Apicomplexa/microbiology , Larva/microbiology , Plague/veterinary , Rodent Diseases/microbiology , Sciuridae/microbiology , Siphonaptera/microbiology , Yersinia pestis/growth & development , Animals , Insect Vectors/microbiology , Insect Vectors/parasitology , Larva/parasitology , Microbial Viability , Plague/microbiology , Plague/transmission , Rodent Diseases/transmission , Seasons , Siphonaptera/parasitology , Yersinia pestis/isolation & purification , Yersinia pestis/pathogenicityABSTRACT
Yersinia pestis, the agent of plague, is transmitted to mammals by infected fleas. Y. pestis exhibits a distinct life stage in the flea, where it grows in the form of a cohesive biofilm that promotes transmission. After transmission, the temperature shift to 37 degrees C induces many known virulence factors of Y. pestis that confer resistance to innate immunity. These factors are not produced in the low-temperature environment of the flea, however, suggesting that Y. pestis is vulnerable to the initial encounter with innate immune cells at the flea bite site. In this study, we used whole-genome microarrays to compare the Y. pestis in vivo transcriptome in infective fleas to in vitro transcriptomes in temperature-matched biofilm and planktonic cultures, and to the previously characterized in vivo gene expression profile in the rat bubo. In addition to genes involved in metabolic adaptation to the flea gut and biofilm formation, several genes with known or predicted roles in resistance to innate immunity and pathogenicity in the mammal were upregulated in the flea. Y. pestis from infected fleas were more resistant to phagocytosis by macrophages than in vitro-grown bacteria, in part attributable to a cluster of insecticidal-like toxin genes that were highly expressed only in the flea. Our results suggest that transit through the flea vector induces a phenotype that enhances survival and dissemination of Y. pestis after transmission to the mammalian host.
Subject(s)
Biofilms , Immunity, Innate/genetics , Insect Vectors/genetics , Siphonaptera/parasitology , Yersinia pestis/physiology , Yersinia pestis/pathogenicity , Adaptation, Physiological , Animals , Gene Expression , Gene Expression Profiling , Genes, Bacterial , Insect Vectors/immunology , Oligonucleotide Array Sequence Analysis , Phenotype , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
BACKGROUND: Dipilidiosis is a parasitic disease caused by the tapeworm Dipylidium caninum. Fleas and, less frequently, lice act as an intermediate host, and their ingestion is required for infection to occur. While the disease mainly affects domestic and wild carnivores, it is also considered a zoonotic disease, with most human cases reported in children. Dipylidium caninum is considered to be the most common tapeworm infesting companion animals, but dipilidosis in humans is rare. The aims of this review were to improve current understanding of the epidemiology of this parasitosis and its management by the medical and veterinary community. METHODS: A comprehensive review of the published literature during the last 21 years (2000-2021) on the epidemiology, clinical features, diagnosis, treatment and prevention measures of D. caninum infection and dipilidiosis in companion animals and humans was conducted. RESULTS: Using predefined eligibility criteria for a search of the published literature, we retrieved and screened 280 publications. Of these, 161 (141 epidemiological studies, 20 case reports [16 human cases]) were considered for inclusion in this review. This parasitosis is present worldwide; however, despite being the most frequent cestode infection in animals, it is often underdiagnosed using common coprological techniques. Its diagnosis in humans has also proved challenging, being frequently confused with pinworm infection, leading to inappropriate treatment and to the persistence of the disease over time. Prevention measures include control of ectoparasites in animals and the environment, as well as regular deworming of animals, most commonly with praziquantel. CONCLUSIONS: The diagnosis of dipilidiosis remains challenging in both animals and humans, primarily due to the low sensitivity of the diagnostic methods currently available and a lack of knowledge of the morphological characteristics of the parasite. Although treatment with the appropriate anti-cestode compounds is well tolerated and results in resolution of the infection, indiscriminate use of these compounds may predispose to an increase in resistance. Given the worldwide distribution of this parasite, it is essential to act on several fronts, with a focus on health education for children and animal owners and the control of intermediate hosts, both in animals and in the surrounding environment.
Subject(s)
Cestoda , Cestode Infections , Flea Infestations , Siphonaptera , Animals , Cestode Infections/diagnosis , Cestode Infections/epidemiology , Cestode Infections/prevention & control , Flea Infestations/veterinary , Humans , Pets , Siphonaptera/parasitologyABSTRACT
Trypanosoma lewisi is a worldwide nonpathogenic parasite that is exclusively found in rats. In general, T. lewisi infection in humans is an opportunistic infection from rats to humans through fleas. However, recently, infection with T. lewisi in humans, including a fatal case, has been reported. Notably, rats living close to a human settlement showed a higher prevalence of infection with T. lewisi than those living in other places. It is possible that the urbanization is associated with the prevalence of T. lewisi in rats and enhances the risk of T. lewisi transmission to humans through fleas. In this study, a total of 88 rats were captured from hospitals, markets, and a cargo station, of which 81 were identified as Rattus norvegicus and 7 as Rattus rattus in Hanoi, the urbanizing city of Vietnam. Of these, 55 rats (62.5%) harbored T. lewisi, of which 52 were R. norvegicus and 3 were R. rattus.
Subject(s)
Rats/parasitology , Trypanosoma lewisi , Trypanosomiasis , Animals , DNA, Protozoan/genetics , Humans , Rodent Diseases/epidemiology , Rodent Diseases/parasitology , Rodent Diseases/transmission , Siphonaptera/parasitology , Trypanosoma lewisi/genetics , Trypanosomiasis/epidemiology , Trypanosomiasis/parasitology , Trypanosomiasis/transmission , Trypanosomiasis/veterinary , Vietnam/epidemiology , ZoonosesABSTRACT
The occurrence of the insect vector (sand flies) with low rates of Leishmania infection, as well as autochthonous transmission in the absence of the natural vector in dogs, have been reported. These unexpected data suggest a hypothesis of other arthropods as a possible way of Leishmania transmission. The prevalence of Leishmania (Leishmania) infantum in fleas and ticks collected from dogs with canine visceral leishmaniasis (CVL), as well as parasite viability, were evaluated herein. The presence of L. (L.) infantum was assayed by PCR and ELISA in ectoparasites and biological samples from 73 dogs living in a Brazilian endemic area. As the occurrence of Leishmania DNA in ticks and fleas is expected given their blood-feeding habits, we next investigated whether parasites can remain viable inside ticks. PCR and ELISA confirmed that 83% of the dogs had CVL. Fleas and ticks (nymphs, male and female adults) were collected in 55% and 63% of the 73 dogs, respectively. Out of the 60 dogs with CVL, 80% harbored ectoparasites infected with L. (L.) infantum. The infection rates of the ectoparasites were 23% and 50% for fleas and ticks, respectively. The RNA analysis of the extract from ticks left in laboratory conditions during 7 to 10 days after removal from CVL dogs showed that parasites were alive. In addition, live parasites were also detected inside adult ticks recently molted in laboratory conditions. These findings indicate a higher infection rate of L. (L.) infantum in ticks and fleas, but they do not conclusively demonstrate whether these ticks can act as vectors of CVL, despite the fact that their rates were higher than those previously described in Lutzomyia longipalpis. The presence of viable L. (L.) infantum in ticks suggests the possible importance of dog ectoparasites in CVL dissemination.
Subject(s)
Dog Diseases/parasitology , Ectoparasitic Infestations/veterinary , Leishmania infantum/genetics , RNA, Protozoan/genetics , RNA, Protozoan/isolation & purification , Siphonaptera/parasitology , Ticks/parasitology , Animals , Brazil , Dogs , Ectoparasitic Infestations/parasitology , Female , Male , Siphonaptera/genetics , Ticks/geneticsABSTRACT
BACKGROUND: Fleas frequently infest small mammals and play important vectoring roles in the epidemiology of (re)emerging zoonotic disease. Rodent outbreaks in intensified agro-ecosystems of North-West Spain have been recently linked to periodic zoonotic diseases spillover to local human populations. Obtaining qualitative and quantitative information about the composition and structure of the whole flea and small mammal host coexisting communities is paramount to understand disease transmission cycles and to elucidate the disease-vectoring role of flea species. The aims of this research were to: (i) characterise and quantify the flea community parasiting a small mammal guild in intensive farmlands in North-West Spain; (ii) determine and evaluate patterns of co-infection and the variables that may influence parasitological parameters. METHODS: We conducted a large-scale survey stratified by season and habitat of fleas parasitizing the small mammal host guild. We report on the prevalence, mean intensity, and mean abundance of flea species parasitizing Microtus arvalis, Apodemus sylvaticus, Mus spretus and Crocidura russula. We also report on aggregation patterns (variance-to-mean ratio and discrepancy index) and co-infection of hosts by different flea species (Fager index) and used generalized linear mixed models to study flea parameter variation according to season, habitat and host sex. RESULTS: Three flea species dominated the system: Ctenophthalmus apertus gilcolladoi, Leptopsylla taschenbergi and Nosopsyllus fasciatus. Results showed a high aggregation pattern of fleas in all hosts. All host species in the guild shared C. a. gilcolladoi and N. fasciatus, but L. taschenbergi mainly parasitized mice (M. spretus and A. sylvaticus). We found significant male-biased infestation patterns in mice, seasonal variations in flea abundances for all rodent hosts (M. arvalis, M. spretus and A. sylvaticus), and relatively lower infestation values for voles inhabiting alfalfas. Simultaneous co-infections occurred in a third of all hosts, and N. fasciatus was the most common flea co-infecting small mammal hosts. CONCLUSIONS: The generalist N. fasciatus and C. a. gilcolladoi dominated the flea community, and a high percentage of co-infections with both species occurred within the small mammal guild. Nosopsyllus fasciatus may show higher competence of inter-specific transmission, and future research should unravel its role in the circulation of rodent-borne zoonoses.
Subject(s)
Eulipotyphla/parasitology , Flea Infestations/epidemiology , Murinae/parasitology , Animals , Arvicolinae/parasitology , Crops, Agricultural , Ecosystem , Host Specificity , Host-Parasite Interactions , Mice , Rodent Diseases/epidemiology , Rodent Diseases/parasitology , Seasons , Sex Factors , Shrews/parasitology , Siphonaptera/parasitology , Spain/epidemiology , Zoonoses/epidemiologyABSTRACT
BACKGROUND: Arthropod-borne pathogens and their vectors are present throughout Africa. They have been well-studied in livestock of sub-Saharan Africa, but poorly in companion animals. Given the socio-economic importance of companion animals, the African Small Companion Animal Network (AFSCAN), as part of the WSAVA Foundation, initiated a standardized multi-country surveillance study. METHODS: Macro-geographic variation in ectoparasite (ticks and fleas) and pathogen communities in dogs was assessed through molecular screening of approximately 100 infested dogs in each of six countries (Ghana, Kenya, Nigeria, Tanzania, Uganda and Namibia), both in rural and urban settings. The most important intrinsic and extrinsic risk factors within the subpopulation of infested dogs were evaluated. RESULTS: Despite the large macro-geographic variation in the dogs screened, there was no consistent difference between East and West Africa in terms of the diversity and numbers of ticks. The highest and lowest numbers of ticks were found in Nigeria and Namibia, respectively. Most often, there was a higher diversity of ticks in rural habitats than in urban habitats, although the highest diversity was observed in an urban Uganda setting. With the exception of Namibia, more fleas were collected in rural areas. We identified tick species (including Haemaphysalis spinulosa) as well as zoonotic pathogens (Coxiella burnetti, Trypanosoma spp.) that are not classically associated with companion animals. Rhipicephalus sanguineus was the most abundant tick, with a preference for urban areas. Exophilic ticks, such as Haemaphysalis spp., were more often found in rural areas. Several multi-host ticks occurred in urban areas. For R. sanguineus, housing conditions and additional pets were relevant factors in terms of infestation, while for a rural tick species (Haemaphysalis elliptica), free-roaming dogs were more often infested. Tick occurrence was associated to the use of endoparasiticide, but not to the use of ectoparasiticide. The most prevalent tick-borne pathogen was Hepatozoon canis followed by Ehrlichia canis. High levels of co-parasitism were observed in all countries and habitats. CONCLUSIONS: As dogs share a common environment with people, they have the potential to extend the network of pathogen transmission to humans. Our study will help epidemiologists to provide recommendations for surveillance and prevention of pathogens in dogs and humans.
Subject(s)
Arthropod Vectors , Bacteria/isolation & purification , Dog Diseases , Eucoccidiida/isolation & purification , Rickettsia/isolation & purification , Africa, Eastern/epidemiology , Africa, Western/epidemiology , Animals , Arthropod Vectors/microbiology , Arthropod Vectors/parasitology , Babesia/isolation & purification , Coxiella burnetii/isolation & purification , Dog Diseases/epidemiology , Dog Diseases/microbiology , Dog Diseases/parasitology , Dogs , Ehrlichia canis/isolation & purification , Flea Infestations/epidemiology , Flea Infestations/veterinary , Ixodidae/microbiology , Ixodidae/parasitology , Pathology, Molecular , Rhipicephalus sanguineus , Risk Factors , Siphonaptera/microbiology , Siphonaptera/parasitology , Tick Infestations/epidemiology , Tick Infestations/veterinary , Vector Borne Diseases/epidemiology , Vector Borne Diseases/microbiology , Vector Borne Diseases/parasitology , Zoonoses/epidemiology , Zoonoses/microbiology , Zoonoses/parasitologyABSTRACT
The number of recognized flea-borne pathogens has increased over the past decade. However, the true number of infections related to all flea-borne pathogens remains unknown. To better understand the enzootic cycle of flea-borne pathogens, fleas were sampled from small mammals trapped in central Pennsylvania. A total of 541 small mammals were trapped, with white-footed mice (Peromyscus leucopus) and southern red-backed voles (Myodes gapperi) accounting for over 94% of the captures. Only P. leucopus were positive for examined blood-borne pathogens, with 47 (18.1%) and ten (4.8%) positive for Anaplasma phagocytophilum and Babesia microti, respectively. In addition, 61 fleas were collected from small mammals and tested for pathogens. Orchopeas leucopus was the most common flea and Bartonella vinsonii subspecies arupensis, B. microti, and a Rickettsia felis-like bacterium were detected in various flea samples. To the best of our knowledge, this is the first report of B. microti DNA detected from a flea and the first report of a R. felis-like bacterium from rodent fleas in eastern North America. This study provides evidence of emerging pathogens found in fleas, but further investigation is required to resolve the ecology of flea-borne disease transmission cycles.
Subject(s)
Bartonella/pathogenicity , Siphonaptera/parasitology , Animals , Arvicolinae/parasitology , Babesia microti/parasitology , Babesia microti/pathogenicity , Male , Mammals/parasitology , Pennsylvania , Peromyscus/parasitology , Rickettsia felis/pathogenicity , Sciuridae/parasitologyABSTRACT
BACKGROUND: Ticks and fleas are considered amongst the most important arthropod vectors of medical and veterinary concern due to their ability to transmit pathogens to a range of animal species including dogs, cats and humans. By sharing a common environment with humans, companion animal-associated parasitic arthropods may potentially transmit zoonotic vector-borne pathogens (VBPs). This study aimed to molecularly detect pathogens from ticks and fleas from companion dogs and cats in East and Southeast Asia. METHODS: A total of 392 ticks and 248 fleas were collected from 401 infested animals (i.e. 271 dogs and 130 cats) from China, Taiwan, Indonesia, Malaysia, Singapore, Thailand, the Philippines and Vietnam, and molecularly screened for the presence of pathogens. Ticks were tested for Rickettsia spp., Anaplasma spp., Ehrlichia spp., Babesia spp. and Hepatozoon spp. while fleas were screened for the presence of Rickettsia spp. and Bartonella spp. RESULT: Of the 392 ticks tested, 37 (9.4%) scored positive for at least one pathogen with Hepatozoon canis being the most prevalent (5.4%), followed by Ehrlichia canis (1.8%), Babesia vogeli (1%), Anaplasma platys (0.8%) and Rickettsia spp. (1%) [including Rickettsia sp. (0.5%), Rickettsia asembonensis (0.3%) and Rickettsia felis (0.3%)]. Out of 248 fleas tested, 106 (42.7%) were harboring at least one pathogen with R. felis being the most common (19.4%), followed by Bartonella spp. (16.5%), Rickettsia asembonensis (10.9%) and "Candidatus Rickettsia senegalensis" (0.4%). Furthermore, 35 Rhipicephalus sanguineus ticks were subjected to phylogenetic analysis, of which 34 ticks belonged to the tropical and only one belonged to the temperate lineage (Rh. sanguineus (sensu stricto)). CONCLUSION: Our data reveals the circulation of different VBPs in ticks and fleas of dogs and cats from Asia, including zoonotic agents, which may represent a potential risk to animal and human health.
Subject(s)
Bacteria , Eucoccidiida , Pets , Siphonaptera , Ticks , Anaplasma/classification , Anaplasma/genetics , Anaplasma/isolation & purification , Animals , Arachnid Vectors/microbiology , Arachnid Vectors/parasitology , Arthropod Vectors/microbiology , Arthropod Vectors/parasitology , Asia, Southeastern/epidemiology , Babesia/classification , Babesia/genetics , Babesia/isolation & purification , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Bacterial Zoonoses , Bartonella/classification , Bartonella/genetics , Bartonella/isolation & purification , Cat Diseases , Cats/microbiology , Cats/parasitology , Dog Diseases , Dogs/microbiology , Dogs/parasitology , Ehrlichia/classification , Ehrlichia/genetics , Ehrlichia/isolation & purification , Eucoccidiida/classification , Eucoccidiida/genetics , Eucoccidiida/isolation & purification , Asia, Eastern/epidemiology , Genes, Bacterial , Genes, Protozoan , Insect Vectors/microbiology , Insect Vectors/parasitology , Pathology, Molecular , Pets/microbiology , Pets/parasitology , Phylogeny , Prevalence , Rickettsia/classification , Rickettsia/genetics , Rickettsia/isolation & purification , Siphonaptera/microbiology , Siphonaptera/parasitology , Ticks/microbiology , Ticks/parasitology , ZoonosesABSTRACT
Rattus spp. are reservoirs of many human zoonoses, but their role in domestic transmission cycles of human trypanosomiasis is underestimated. In this study, we report trypanosome-infected Rattus norvegicus and Rattus rattus in human dwellings in slums neighboring Maracay, a large city near Caracas, the capital of Venezuela. Blood samples of R. norvegicus and R. rattus examined by PCR and FFLB (fluorescent fragment length barcoding) revealed a prevalence of 6.3% / 31.1% for Trypanosoma lewisi (agent of rat- and flea-borne human emergent zoonosis), and 10.5% / 24.6% for Trypanosoma cruzi (agent of Chagas disease). Detection in flea guts of T. lewisi (76%) and, unexpectedly, T. cruzi (21.3%) highlighted the role of fleas as carriers and vectors of these trypanosomes. A high prevalence of rats infected with T. lewisi and T. cruzi and respective flea and triatomine vectors poses a serious risk of human trypanosomiasis in Venezuelan slums. Anthropogenic activities responsible for growing rat and triatomine populations within human dwellings drastically increased human exposure to trypanosomes. This scenario has allowed for the reemergence of Chagas disease as an urban zoonosis in Venezuela and can propitiate the emergence of atypical T. lewisi infection in humans.
Subject(s)
Insect Vectors/parasitology , Rodent Diseases/epidemiology , Siphonaptera/parasitology , Trypanosomiasis/veterinary , Animals , Chagas Disease/veterinary , DNA, Protozoan , Disease Reservoirs/parasitology , Poverty Areas , Rats , Trypanosoma cruzi/genetics , Trypanosoma lewisi/genetics , Venezuela/epidemiology , Zoonoses/transmissionABSTRACT
Rickettsia felis is an emergent pathogen belonging to transitional group rickettsiae. First described in 1990, R. felis infections have been reported to occur worldwide in fleas, mammals, and humans. Because clinical signs of the illness are similar to those of murine typhus and other febrile illnesses such as dengue, the infection in humans is likely underestimated. R. felis has been found throughout the world in several types of ectoparasites; cat fleas appear to be the most common vectors. R. felis infection should be considered an emergent threat to human health.
Subject(s)
Communicable Diseases, Emerging/microbiology , Rickettsia Infections/transmission , Rickettsia felis , Animals , Arthropod Vectors , Cats , Humans , Rickettsia Infections/diagnosis , Siphonaptera/parasitologyABSTRACT
In total, 1500 specimens (448 males and 1052 females) of the flea Ctenocephalides felis felis (Bouché (Siphonaptera: Pulicidae) were collected over a period of a year from 150 dogs captured by the Centro de Controle de Zoonoses de Belo Horizonte, Minas Gerais, Brazil. Microscopic examination of the dissected fleas revealed that 180 fleas were infected with a species of gregarine that was subsequently identified as a member of the genus Steinina. The relative abundances, prevalence rates, and seasonal variation of the different developmental stages of this endoparasite in C. felis felis were determined. Both gamonts and gametocysts presented significant seasonal variation.
Subject(s)
Apicomplexa/growth & development , Dog Diseases/parasitology , Ectoparasitic Infestations/veterinary , Host-Parasite Interactions , Siphonaptera/parasitology , Animals , Brazil , Dogs , Ectoparasitic Infestations/parasitology , Female , Life Cycle Stages , Male , Prevalence , SeasonsABSTRACT
In this work, we analyzed viral prevalence in trypanosomatid parasites (Blechomonas spp.) infecting Siphonaptera and discovered nine species of viruses from three different groups (leishbunyaviruses, narnaviruses, and leishmaniaviruses). Most of the flagellate isolates bore two or three viral types (mixed infections). Although no new viral groups were documented in Blechomonas spp., our findings are important for the comprehension of viral evolution. The discovery of bunyaviruses in blechomonads was anticipated, since these viruses have envelopes facilitating their interspecific transmission and have already been found in various trypanosomatids and metatranscriptomes with trypanosomatid signatures. In this work, we also provided evidence that even representatives of the family Narnaviridae are capable of host switching and evidently have accomplished switches multiple times in the course of their evolution. The most unexpected finding was the presence of leishmaniaviruses, a group previously solely confined to the human pathogens Leishmania spp. From phylogenetic inferences and analyses of the life cycles of Leishmania and Blechomonas, we concluded that a common ancestor of leishmaniaviruses most likely infected Leishmania first and was acquired by Blechomonas by horizontal transfer. Our findings demonstrate that evolution of leishmaniaviruses is more complex than previously thought and includes occasional host switching.IMPORTANCE Flagellates belonging to the genus Leishmania are important human parasites. Some strains of different Leishmania species harbor viruses (leishmaniaviruses), which facilitate metastatic spread of the parasites, thus aggravating the disease. Up until now, these viruses were known to be hosted only by Leishmania Here, we analyzed viral distribution in Blechomonas, a related group of flagellates parasitizing fleas, and revealed that they also bear leishmaniaviruses. Our findings shed light on the entangled evolution of these viruses. In addition, we documented that Blechomonas can be also infected by leishbunyaviruses and narnaviruses, viral groups known from other insects' flagellates.
Subject(s)
Evolution, Molecular , Leishmaniavirus/genetics , RNA Viruses/classification , Trypanosomatina/virology , Animals , Genetic Variation , Genome, Viral , Phylogeny , RNA Viruses/isolation & purification , Siphonaptera/parasitologyABSTRACT
The present survey aimed to investigate flea and tick fauna parasitizing Slovak red fox populations with special emphasis on canine pathogens they transmit. A total of 407 fleas and 105 ticks were collected from 90 red foxes from two geographically distant regions. Seven flea species (Chaetopsylla globiceps, Pulex irritans, Archaeopsylla erinacei, Chaetopsylla rothschildi, Chaetopsylla trichosa, Ctenocephalides canis, and Ctenopthalmus assimilis) and three species of hard ticks (Ixodes ricinus, Ixodes hexagonus, Haemaphysalis concinna) were recorded on sampled animals. Consequently, the DNA of five different pathogen taxa was confirmed in collected arthropod vectors: Bartonella spp. (in P. irritans, Ch. globiceps, and Ct. assimilis), Rickettsia spp. (in A. erinacei, I. ricinus, I. hexagonus, and H. concinna), Anaplasma phagocytophilum (in I. ricinus), Theileria sp. (in Ch. globiceps and H. concinna), and Hepatozoon canis (in I. ricinus and I. hexagonus). Mycoplasma spp., Dipylidium caninum, and Acanthocheilonema reconditum were not found in fleas or ticks in this study.
Subject(s)
Dog Diseases/epidemiology , Flea Infestations/veterinary , Foxes/parasitology , Ixodidae/microbiology , Siphonaptera/microbiology , Tick Infestations/microbiology , Animals , Dog Diseases/microbiology , Dog Diseases/parasitology , Dogs , Flea Infestations/epidemiology , Ixodidae/parasitology , Siphonaptera/parasitology , Slovakia , Tick Infestations/parasitologyABSTRACT
BACKGROUND: Zoonotic tungiasis caused by Tunga penetrans remains a serious public and animal health problem among endemic villages in Uganda and many sub Saharan African countries. Studies on human and animal tungiasis-related knowledge and treatment practices in endemic communities have never been undertaken, a limitation to development of sustainable control measures. METHODS: A cross sectional study using semi-structured questionnaires (Supplementary file S1) was conducted among 236 animal rearing households in 10 endemic villages in Bugiri District, South-Eastern Uganda. Focus group discussions and observation checklists were used to validate and clarify the findings. RESULTS: Most respondents knew the aetiology (89.4%), clinical signs (98%) and the ecology of T. penetrans as well as the major risk factors of human tungiasis (65.2%). In contrast, very few respondents were aware of animal tungiasis. Only 4.8% of those with infected animals on the compound knew that some of their animals were infected and 13.6% of the respondents had ever seen tungiasis-affected animals. Pigs (13.1%, n=31) and dogs (0.85%, n=2) were the only T. penetrans animal hosts known to animal owners. Affected humans were treated by extraction of embedded sand fleas using non-sterile sharp instruments in all households that reported occurrence of human tungiasis at least once (n=227). Also, affected animals were mainly treated by mechanical removal of embedded sand fleas in households that have ever experienced animal tungiasis (four out of 12; 33.3%). In a few instances, plant and animal pesticides (n=3) and other chemicals such as grease, paraffin and wood preservative (n=3) were also used to treat animal tungiasis. CONCLUSION: The study revealed a high level of knowledge on human tungiasis but inadequate knowledge on the zoonotic nature of tungiasis. Commonly applied methods for treatment of human and animal tungiasis are a health hazard by themselves. Concerted i.e. One Health-based efforts aiming at promoting appropriate treatment of tungiasis, adequate living conditions and increased awareness on tungiasis in the communities are indicated in order to eliminate tungiasis-associated disease.
Subject(s)
Siphonaptera/parasitology , Sus scrofa/parasitology , Swine/parasitology , Tunga/parasitology , Tungiasis/parasitology , Zoonoses/parasitology , Africa, Northern , Animals , Cross-Sectional Studies , Disease Vectors , Dogs , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Risk Factors , Surveys and Questionnaires , Uganda/epidemiologyABSTRACT
Initial investigations suggested the existence of two distinct genotypes of Dipylidium caninum from infected cat fleas (Ctenocephalides felis). One genotype was found almost always (> 95%) in fleas collected from, and proglottids shed by, domestic dogs. The other was found almost always (> 95%) in fleas collected from, and proglottids shed by, domestic cats. Molecular investigations (Part 1, in this journal) confirmed the presence of two distinct genotypes. Due to the apparent host association observed, these were referred to as the "D. caninum canine genotype" and the "D. caninum feline genotype". The current article reports on an in vivo experimental infection study assessing the host-parasite interaction for each genotype. Mixed infections with the two genotypes in both dogs and cats were conducted. The specific genotyping of proglottids allowed us to assess the specific prepatent periods, prolificity, and longevity of each genotype in dogs versus cats. The possible hybridisation was also studied through molecular evaluation of the proglottids expelled by infected dogs and cats. Results demonstrate a clear distinct host interaction. The canine D. caninum genotype occurred at a higher frequency in dogs, with a shorter prepatent period and a longer lifespan; and the feline genotype occurred at a higher frequency in cats, with a shorter prepatent period and a longer lifespan. The absence of any hybrids in the mixed infections of both dogs and cats confirm the hypothesis of two distinct genotypes, suggesting the possibility of two distinct species within Dipylidium caninum.
Subject(s)
Cestoda/genetics , Cestode Infections/veterinary , Coinfection/veterinary , Flea Infestations/veterinary , Genotype , Host-Parasite Interactions/genetics , Siphonaptera/parasitology , Animals , Animals, Domestic/parasitology , Cat Diseases/parasitology , Cats/parasitology , Cestoda/classification , Cestode Infections/parasitology , Coinfection/parasitology , Dog Diseases/parasitology , Dogs/parasitologyABSTRACT
Piroplasmoses are one of the most prevalent arthropod-borne diseases of animals. The present work aimed to investigate the occurrence of piroplasmid in wild mammals, domestic dogs and ectoparasites in southern Pantanal region, central-western Brazil. For that purpose, blood or tissue samples from 31 Nasua nasua, 78 Cerdocyon thous, 7 Leopardus pardalis, 42 dogs, 110 wild rodents, and 30 marsupials, and 1582 ticks were submitted to PCR assays for piroplasmid targeting 18SrRNA and hps70 genes. Seven dogs, one C. thous, five L. pardalis, three N. nasua, six wild rodents, eight Amblyomma parvum, two Amblyomma sculptum and one Amblyomma ovale were positive for piroplasmid-PCR assays. Genotypes closely related to Babesia vogeli were detected in six dogs and five wild rodents. While genotypes closely related to Babesia caballi were detected in one C. thous, one dog, one A. ovale and one A. sculptum, genotypes closely related to Babesia bigemina and Babesia bovis were detected in four A. parvum ticks. Four sequences obtained from A. parvum, three coatis and one wild rodent were closely related to Theileria equi. Cytauxzoon spp. was detected in four ocelots. The present study revealed that wild and domestic animals in Brazilian southern Pantanal are exposed to different piroplasmid species.