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1.
Vector Borne Zoonotic Dis ; 24(5): 308-320, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38232706

RÉSUMÉ

Background: Fleas are ectoparasitic insects with holometabolous development. It has a hematophagous habit with mouthparts adapted to sting and suck its hosts. There are about 3000 species in the world, ∼61 in Brazil, and 19 in Rio Grande do Sul state. The objective of the research is to catalog the diversity of fleas recorded in the state, their respective hosts, and endosymbionts. Materials and Methods: To this end, a search was carried out in the scientific literature, from articles, books, to abstracts submitted to congresses. Results: The 19 species of fleas occurring in Rio Grande do Sul are divided into 7 families and 10 genera. These ectoparasites, in addition to being found in the environment, were associated with 10 different families of hosts in Rio Grande do Sul, and on the endosymbiont, agents found associated with fleas, there were 7 different species. The main agents researched in the state are Rickettsia spp. and Bartonella spp. The relationships between parasites, hosts, environment, and etiological agents present different scenarios, whether anthropized or conserved, but unknown. Sometimes, this overlap, a factor that aggravates the possibility of spillovers, either from cosmopolitan fleas in these conserved areas, or from their endosymbionts. Conclusion: Thus, it is important to characterize the environment so that the complexities of each location are known for the adoption of environmental and public health policies in each case. The challenges are extensive, but necessary in view of the One Health perspective.


Sujet(s)
Infestations par les puces , Siphonaptera , Animaux , Siphonaptera/classification , Siphonaptera/microbiologie , Brésil/épidémiologie , Infestations par les puces/médecine vétérinaire , Infestations par les puces/parasitologie , Infestations par les puces/épidémiologie , Une seule santé , Humains , Biodiversité , Interactions hôte-parasite
2.
Comp Immunol Microbiol Infect Dis ; 101: 102042, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37660454

RÉSUMÉ

The genus Bartonella (Hyphomicrobiales: Bartonellaceae) encompasses facultative intracellular α-proteobacteria that parasite erythrocytes and endothelial cells from a wide range of vertebrate hosts and can cause disease in animals and humans. Considering the large diversity of vertebrate species that may act as reservoirs and arthropod species that may be associated with Bartonella transmission, the exposure of animals and humans to these microorganisms is likely underestimated. The present study aimed to investigate the occurrence of Bartonella sp. in wild tapirs (Tapirus terrestris; Perissodactyla: Tapiridae) from two biomes in Brazil: Pantanal and Cerrado. Ninety-nine GPS-monitored wild tapirs were sampled in Pantanal (n = 61/99) and Cerrado (n = 38/99). A qPCR (quantitative real-time polymerase chain reaction) assay targeting the nuoG gene was used for the screening for Bartonella spp. DNA. Positive samples were additionally subjected to conventional PCR assays targeting five molecular markers (ribC, gltA, rpoB, groEL, ITS). Eight (8/99; 08,08%) animals were positive in the qPCR assay for Bartonella spp.: 7 from Cerrado (7/8; 87.5%) and 1 from Pantanal (1/8; 12.5%). The 5 Bartonella ribC sequences obtained from tapirs' blood samples grouped together with Bartonella henselae obtained from cats, humans, wild felids and Ctenocephalides felis (Siphonaptera: Pulicidae) fleas. To the best of author's knowledge, this is the first report of Bartonella sp. in Tapirus terrestris. This finding contributes to the understanding of the occurrence of B henselae in wild mammals from Brazil as well as expands the knowledge regarding the potential vector-borne pathogens that may affect wild tapis from Cerrado and Pantanal biomes.


Sujet(s)
Infections à Bartonella , Bartonella , Siphonaptera , Animaux , Humains , Bartonella/génétique , Brésil/épidémiologie , Cellules endothéliales , Mammifères/génétique , Siphonaptera/microbiologie , Perissodactyla/génétique , Réaction de polymérisation en chaine en temps réel/médecine vétérinaire , Infections à Bartonella/épidémiologie , Infections à Bartonella/médecine vétérinaire , Infections à Bartonella/diagnostic
3.
J Med Entomol ; 60(5): 1073-1080, 2023 09 12.
Article de Anglais | MEDLINE | ID: mdl-37410023

RÉSUMÉ

Lagomorphs-principally rabbits and hares-have been implicated as hosts for vectors and reservoirs for pathogens associated with multiple rickettsial diseases. Western North America is home to diverse rickettsial pathogens which circulate among multiple wild and domestic hosts and tick and flea vectors. The purpose of this study was to assess lagomorphs and their ectoparasites in 2 locations in northern Baja California, Mexico, for exposure to and infection with rickettsial organisms. In total, 55 desert cottontail rabbits (Sylvilagus audubonii) (Baird) and 2 black-tailed jackrabbits (Lepus californicus) (Gray) were captured. In Mexicali, ticks were collected from 44% (14/32) of individuals, and were exclusively Haemaphysalis leporispalustrisNeumann (Acari: Ixodidae); in Ensenada, ticks were collected from 70% (16/23) individuals, and 95% were Dermacentor parumapertus. Euhoplopsyllus glacialis affinisBaker (Siphonaptera: Pulicidae) fleas were collected from 72% of rabbits and 1 jackrabbit from Mexicali, while the few fleas found on hosts in Ensenada were Echidnophaga gallinaceaWestwood (Siphonaptera: Pulicidae) and Cediopsylla inaequalis(Siphonaptera: Pulicidae). Rickettsia bellii was the only rickettsial organism detected and was identified in 88% of D. parumapertus and 67% of H. leporispalustris ticks from Ensenada. A single tissue sample from a jackrabbit was positive for R. belli (Rickettsiales: Rickettsiaceae). Hosts in Ensenada had a significantly higher prevalence of rickettsial antibodies than hosts in Mexicali (52.3% vs. 21.4%). Although R. bellii is not regarded as pathogenic in humans or other mammals, it may contribute to immunity to other rickettsiae. The marked difference in distribution of ticks, fleas, and rickettsial exposure between the 2 locations suggests that disease transmission risk may vary markedly between communities within the same region.


Sujet(s)
Infestations par les puces , Lepus , Ixodidae , Lagomorpha , Rickettsia , Siphonaptera , Tiques , Animaux , Humains , Lapins , Mexique , Tiques/microbiologie , Ixodidae/microbiologie , Siphonaptera/microbiologie , Infestations par les puces/épidémiologie , Infestations par les puces/médecine vétérinaire
4.
Comp Immunol Microbiol Infect Dis ; 96: 101983, 2023 May.
Article de Anglais | MEDLINE | ID: mdl-37099997

RÉSUMÉ

Seventy-five flea pools (one to ten fleas per pool) from 51 Andean foxes (Lycalopex culpaeus) and five South American grey foxes or chillas (Lycalopex griseus) from the Mediterranean region of Chile were analyzed for the presence of DNA of Bartonella spp. and Rickettsia spp. through quantitative real-time PCR for the nouG and gltA genes, respectively. Positive samples were further characterized by conventional PCR protocols, targeting gltA and ITS genes for Bartonella, and gltA, ompA, and ompB genes for Rickettsia. Bartonella was detected in 48 % of the Pulex irritans pools (B. rochalimae in three pools, B. berkhoffii in two pools, B. henselae in one pool), and 8 % of the Ctenocephalides felis felis pools (B. rochalimae, one pool). Rickettsia was confirmed in 11 % of P. irritans pools and 92 % of the Ct. felis pools. Characterization confirmed R. felis in all sequenced Rickettsia-positive pools. All Ct. canis pools were negative. A Ct. felis pool from a wild-found domestic ferret (Mustela putorius furo) also resulted positive for R. felis. Although opportunistic, this survey provides the first description of zoonotic pathogens naturally circulating in fleas parasitizing Chilean free-living carnivores.


Sujet(s)
Bartonella , Carnivora , Ctenocephalides , Maladies des chiens , Infestations par les puces , Mustelidae , Rickettsia felis , Rickettsia , Siphonaptera , Chiens , Animaux , Siphonaptera/microbiologie , Bartonella/génétique , Rickettsia felis/génétique , Renards , Chili/épidémiologie , Furets/génétique , Maladies des chiens/microbiologie , Infestations par les puces/épidémiologie , Infestations par les puces/médecine vétérinaire , Rickettsia/génétique , Ctenocephalides/génétique , Réaction de polymérisation en chaine en temps réel/médecine vétérinaire
5.
Vector Borne Zoonotic Dis ; 23(1): 9-17, 2023 01.
Article de Anglais | MEDLINE | ID: mdl-36633562

RÉSUMÉ

Background: Bartonella species are fastidious gram-negative vector-borne bacteria with a wide range of mammalian reservoirs. While it is understood that some species of Bartonella are human pathogens, the extent of human exposure to Bartonella species (both pathogenic and nonpathogenic) is yet to be fully understood. Materials and Methods: To this end, residual sera from participants enrolled in undifferentiated fever studies in Cambodia, Ghana, Laos, and Peru were screened for the presence of IgG antibodies against Bartonella quintana and Bartonella henselae, using the FOCUS diagnostics Dual Spot- Bartonella IgG Immunofluorescence assay. Forty-eight patients with suspected or confirmed Bartonella bacilliformis exposure or infection in Peru were screened to assess cross-reactivity of the FOCUS assay for IgG against other Bartonella species. Results: Ten of 13 patients with confirmed B. bacilliformis infection were Bartonella-specific IgG positive, and overall, 36/48 of the samples were positive. In addition, 79/206, 44/200, 101/180, and 57/100 of the samples from Peru, Laos, Cambodia, and Ghana, respectively, were Bartonella-specific IgG positive. Furthermore, ectoparasite pools from Cambodia, Laos, and Peru were tested using quantitative real-time PCR (qPCR) for the presence of Bartonella DNA. Of the sand fly pools collected in Peru, 0/196 were qPCR positive; 15/140 flea pools collected in Cambodia were qPCR positive; while 0/105 ticks, 0/22 fleas, and 0/3 louse pools collected in Laos tested positive for Bartonella DNA. Conclusion: Evidence of Bartonella in fleas from Cambodia supports the possibility that humans are exposed to Bartonella through this traditional vector. However, Bartonella species were not found in fleas, ticks, or lice from Laos, or sand flies from Peru. This could account for the lower positive serology among the population in Laos and the strictly localized nature of B. bacilliformis infections in Peru. Human exposure to the Bartonella species and Bartonella as a human pathogen warrants further investigation.


Sujet(s)
Infections à Bartonella , Bartonella , Infestations par les puces , Siphonaptera , Tiques , Humains , Animaux , Bartonella/génétique , Infections à Bartonella/épidémiologie , Infections à Bartonella/microbiologie , Infections à Bartonella/médecine vétérinaire , Pérou/épidémiologie , Laos/épidémiologie , Cambodge/épidémiologie , Ghana , Infestations par les puces/microbiologie , Infestations par les puces/médecine vétérinaire , Siphonaptera/microbiologie , Tiques/microbiologie , Mammifères
6.
Zoonoses Public Health ; 70(2): 176-183, 2023 03.
Article de Anglais | MEDLINE | ID: mdl-36409281

RÉSUMÉ

Fleas and ticks represent the two main groups of ectoparasites that infest companion animals. In particular, the flea Ctenocephalides felis felis and several members of the Rhipicephalus sanguineus complex are the main vectors of a wide range of pathogens on the American continent. They are competent vectors for several members of the genus Rickettsia, which encompass at least 15 pathogenic obligate intracellular bacteria that colonize the endothelial cells of vertebrates. In Mexico, 10 species of Rickettsia belonging to three groups have been detected in six species of ectoparasites from dogs in 9 of the 32 states of the country. However, in some larger regions of the country, active epidemiological surveillance has not been carried out. For this reason, the aim of this study was to identify the presence of members of the genus Rickettsia in fleas and ticks of dogs and cats in the state of Puebla, Mexico. A cross-sectional study was carried out to collect ectoparasites of dogs and cats during August to November 2019. Samples were fixed in 70% ethanol and examined to identify the presence of Rickettsia DNA by the amplification and sequencing of specific fragments of the gltA and ompB genes using conventional PCR. The recovered sequences were compared with those deposited in GenBank, and phylogenetic analyses were carried out to identify the position of the pathogens detected with respect to the valid species previously reported worldwide. Additionally, ecological parameters of the ectoparasite infestations were also calculated. We recovered 196 ectoparasites belonging to two species, 33 C. felis felis and 163 R. sanguineus s.l. (Rhipicephalus linnaei), parasitizing 46 hosts (42 dogs and 4 cats) in 11 localities of the state of Puebla. We detected the presence of Rickettsia felis in three pools of C. felis felis, and five from R. sanguineus s.l. Our work provides the first record of R. felis in hard ticks of Mexico and Central America, with new collection localities for this pathogen in central Mexico.


Sujet(s)
Maladies des chats , Maladies des chiens , Felis , Infestations par les puces , Rhipicephalus sanguineus , Rickettsia felis , Rickettsia , Siphonaptera , Animaux , Chats , Chiens , Siphonaptera/microbiologie , Rickettsia felis/génétique , Maladies des chats/parasitologie , Phylogenèse , Études transversales , Cellules endothéliales , Mexique/épidémiologie , Maladies des chiens/microbiologie , Infestations par les puces/épidémiologie , Infestations par les puces/médecine vétérinaire , Rickettsia/génétique
7.
Transbound Emerg Dis ; 69(5): e3352-e3356, 2022 Sep.
Article de Anglais | MEDLINE | ID: mdl-35702810

RÉSUMÉ

The genus Rickettsia encompasses several species grouped into two main clusters, Typhus and the Transitional groups. The latter group contains Rickettsia felis, an endosymbiont of several arthropods with an uncertain human pathogenicity and whose most efficient transmission mechanism described thus far is transovarial. The aim of this study was to evaluate whether this pathway exists using phylogenetic analysis and partial sequences of the 17kDa and gltA genes and comparing them with host phylogeny using the cytb region. This is the first study that evaluates the vertical transmission of R. felis. In general, both phylogenies of R. felis showed no polytomies, as suspected if this pathway was the only pathway occurring. When phylogenies of the invertebrates and the gltA of R. felis were compared for strong coevolutionary insight, intricate relationships were observed, suggesting that other transmission pathways must occur, such as horizontal transmission. Further studies are needed to determine which other transmission routes occur in hematophagous arthropods.


Sujet(s)
Infestations par les puces , Rickettsioses , Rickettsia felis , Rickettsia , Siphonaptera , Animaux , Infestations par les puces/médecine vétérinaire , Humains , Phylogenèse , Rickettsia/génétique , Rickettsioses/microbiologie , Rickettsioses/médecine vétérinaire , Rickettsia felis/génétique , Siphonaptera/microbiologie
8.
Med Vet Entomol ; 36(1): 20-29, 2022 03.
Article de Anglais | MEDLINE | ID: mdl-34455608

RÉSUMÉ

Fleas are important in public health due to their role as parasites and vectors of pathogens, including Rickettsia. The aim of this study was to evaluate the diversity, abundance and prevalence of fleas and the presence of Rickettsia in the trifinio of north-east Argentina. Fleas from household and synanthropic animals were obtained from urban and periurban areas. They were taxonomically identified and samples of 227 fleas in 86 pools were analysed by polymerase chain reaction targeting the gltA and ompB genes of Rickettsia spp. The study revealed that Ctenocephalides felis felis was dominant on dogs, cats and opossums, with higher prevalence in the periurban area. The Shannon-Wiener and Morisita-Horn indices expressed differences in the diversity and similarity values of the absolute abundances of the species between the areas compared. DNA amplifications revealed 30.8% C. f. felis pools positive for Rickettsia spp. Phylogenetic analysis showed that the haplotype obtained was identical to Rickettsia asembonensis from Peru and Brazil. This is the first detection in Argentina of R. asembonensis that infects C. f. felis, and we emphasize the importance of conducting research from a 'One Health' perspective on the role of opossums and rodents in the integration of the transmission cycles of rickettsial bacteria.


Sujet(s)
Ctenocephalides , Maladies des chiens , Felis , Infestations par les puces , Rickettsia felis , Rickettsia , Siphonaptera , Animaux , Argentine , Ctenocephalides/microbiologie , Maladies des chiens/parasitologie , Chiens , Infestations par les puces/épidémiologie , Infestations par les puces/parasitologie , Infestations par les puces/médecine vétérinaire , Phylogenèse , Rickettsia/génétique , Rickettsia felis/génétique , Siphonaptera/microbiologie
9.
Parasitol Res ; 120(10): 3611-3618, 2021 Oct.
Article de Anglais | MEDLINE | ID: mdl-34435254

RÉSUMÉ

Rickettsioses are distributed among a variety of hematophagous arthropods, and represent an emergent threat. The presence of rickettsial bacteria in ectoparasites collected from pigs from Argentina is still unknown. This study investigated the presence and identity of Rickettsia spp. in fleas, Pulex irritans, and sucking lice, Haematopinus suis, of domestic and feral pigs, Sus scrofa, from Central-Northern Argentina, through the genes gltA and ompB. Rickettsial bacteria were detected in 50% of fleas and 24% of lice. The BLASTn analysis of the ompB gene fragments in P. irritans samples showed identities 99% and 100% with R. felis. Positive samples of H. suis were 99% similar with species from the spotted fever group, future amplifications of a more polymorphic fragment of the ompB gene will allow to corroborate the identity of the Rickettsia species present in these lice samples. The Rickettsia spp. reported in the present study are having eventually been associated with cases of human diseases, and the circulation of these agents in arthropods has already been reported in several countries. Therefore, the identification of circulating pathogenic agents, such as reported in this study, is crucial for development of preventive measures for the control of ectoparasite-borne rickettsiosis diseases. Further studies, using serology techniques, will be allow to explore the ability of pigs as a possible Rickettsia reservoir and its role as part of transmission cycle of Rickettsia spp. in the studied scenarios.


Sujet(s)
Anoplura , Rickettsia , Siphonaptera , Animaux , Anoplura/microbiologie , Argentine , Rickettsia/génétique , Siphonaptera/microbiologie , Sus scrofa , Suidae
10.
Ticks Tick Borne Dis ; 12(2): 101633, 2021 03.
Article de Anglais | MEDLINE | ID: mdl-33388556

RÉSUMÉ

The genus Rickettsia encompasses 35 valid species of intracellular, coccobacilli bacteria that can infect several eukaryotic taxa, causing multiple emerging and re-emerging diseases worldwide. This work aimed to gather and summarise the current knowledge about the genus Rickettsia in Mexico, updating the taxonomy of the bacteria and their hosts by including all the records available until 2020, to elucidate host-parasite relationships and determine the geographical distribution of each Rickettsia species present in the country. Until now, 14 species of Rickettsia belonging to four groups have been recorded in Mexico. These species have been associated with 26 arthropod species (14 hard ticks, three soft ticks, two sucking lice, and seven fleas) and 17 mammal species distributed over 30 states in Mexico. This work highlights the high biological inventory of rickettsias for Mexico and reinforces the need to approach the study of this group from a One Health perspective.


Sujet(s)
Anoplura/microbiologie , Interactions hôte-pathogène , Mammifères/microbiologie , Rickettsia/physiologie , Siphonaptera/microbiologie , Tiques/microbiologie , Animaux , Interactions hôte-parasite , Mexique
12.
Integr Zool ; 16(6): 810-819, 2021 Nov.
Article de Anglais | MEDLINE | ID: mdl-32776421

RÉSUMÉ

Plague, caused by the Yersinia pestis bacterium, has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Ceará to the Southeastern State of Minas Gerais and another separated area at the State of Rio de Janeiro. This review gathers data from plague control and surveillance programs on the occurrence and geographic distribution of rodent hosts and flea vectors in the Brazilian plague areas during the period of from 1952 to 2019. Furthermore, we discuss how the interaction between Y. pestis and some rodent host species may play a role in the disease dynamics. The absence of human cases nowadays in Brazil does not mean that it was eradicated. The dynamics of plague in Brazil and in other countries where it was introduced during the 3rd pandemic are quite alike, alternating epidemics with decades of quiescence. Hence, it remains an important epidemic disease of global concern. The existence of a large animal reservoir and competent vectors demonstrate a need for continuous surveillance to prevent new outbreaks of this disease in humans.


Sujet(s)
Vecteurs insectes/microbiologie , Peste/transmission , Rodentia/parasitologie , Siphonaptera/microbiologie , Yersinia pestis/physiologie , Zoonoses/transmission , Animaux , Brésil/épidémiologie , Humains , Peste/épidémiologie , Zoonoses/microbiologie
13.
J Med Entomol ; 58(3): 1316-1321, 2021 05 15.
Article de Anglais | MEDLINE | ID: mdl-33215205

RÉSUMÉ

In total, 341 fleas belonging to 16 species were collected from 78 host mammals belonging to 10 species in Panamá from 2010 to 2016. The cat flea, Ctenocephalides felis (Bouché) predominated on domestic dogs and was also recorded from domestic cats, the raccoon, Procyon lotor (Linnaeus) and the common opossum, Didelphis marsupialis Linnaeus. The largest number of flea species (7) was recorded from D. marsupialis and the most common flea on that host was the ctenophthalmid, Adoratopsylla intermedia copha Jordan. One Oriental rat flea, Xenopsylla cheopis (Rothschild), was collected from D. marsupialis. Native rodents were parasitized by indigenous ceratophyllid, rhopalopsyllid, and stephanocircid fleas. The Mexican deermouse, Peromyscus mexicanus (Saussure), was parasitized by six species of ceratophyllids belonging to the mostly Central American genera, Baculomeris, Jellisonia, Kohlsia and Plusaetis. The long-tailed singing mouse, Scotinomys xerampelinus (Bangs), was parasitized by Plocopsylla scotinomi Tipton and Méndez, the only species of stephanocircid flea known from Central America. Twenty-six pools of extracted flea DNA representing 5 flea species (C. felis, Pulex echidnophagoides (Wagner), Pulex simulans Baker, A. intermedia copha, and P. scotinomi) and 79 individual fleas were all real-time polymerase chain reaction negative for Rickettsia felis, Rickettsia typhi, and Bartonella henselae.


Sujet(s)
Infestations par les puces/médecine vétérinaire , Vecteurs insectes/microbiologie , Mammifères , Siphonaptera/microbiologie , Animaux , Infestations par les puces/épidémiologie , Infestations par les puces/parasitologie , Panama , Prévalence , Maladies vectorielles/microbiologie
14.
J Infect Dev Ctries ; 14(10): 1155-1163, 2020 10 31.
Article de Anglais | MEDLINE | ID: mdl-33175711

RÉSUMÉ

INTRODUCTION: Rickettsioses are zoonotic diseases caused by pathogenic bacteria of the genus Rickettsia and transmitted to man by means of arthropod vectors such as ticks, fleas, mites and lice. Historically, Caldas Department has reported a significant number of cases of murine typhus to the Colombian national health surveillance system, and consequent studies of flea-borne rickettsiosis identified the circulation of Rickettsia typhi and Rickettsia felis in multiple municipalities. Our aim was to genotype species of Rickettsia detected in fleas collected from domestic and wild mammals in Caldas. METHODOLOGY: Flea samples were taken by convenience sampling from dogs, cats and wild mammals (rodents and marsupials) in 26 municipalities. Specimens were classified by current taxonomic keys and pooled for DNA extraction and molecular screening for Rickettsia spp. by PCR amplification of gltA, htrA and sca5 genes. Positive samples were genotyped by enzyme digestion (htrA) and sequencing. RESULTS: A total of 1388 flea samples were collected. Rickettsia DNA was amplified in 818 (gltA), 883 (htrA) and 424 (sca5) flea pools. Alignment analysis with available Rickettsia DNA sequences showed greater similarity with R. asembonensis (gltA) and with R. felis (sca5 and htrA). Restriction pattern was compatible with R. felis. R. typhi was not identified. CONCLUSION: The present study confirms the presence and high prevalence of R. asembonensis and R. felis in fleas from domestic and wild animals in different municipalities from Caldas Department.


Sujet(s)
Infestations par les puces/médecine vétérinaire , Génotype , Rickettsioses/médecine vétérinaire , Rickettsia/génétique , Siphonaptera/microbiologie , Animaux , Animaux domestiques/microbiologie , Animaux sauvages/microbiologie , Chats , Colombie , Chiens , Mammifères , Rickettsia/classification , Rickettsia/isolement et purification , Rickettsioses/microbiologie , Rodentia , Zoonoses/microbiologie , Zoonoses/transmission
15.
Parasit Vectors ; 13(1): 523, 2020 Oct 17.
Article de Anglais | MEDLINE | ID: mdl-33069260

RÉSUMÉ

BACKGROUND: Rickettsial diseases are considered important in public health due to their dispersal capacity determined by the particular characteristics of their reservoirs and/or vectors. Among the latter, fleas play an important role, since the vast majority of species parasitize wild and invasive rodents, so their detection is relevant to be able to monitor potential emerging diseases. The aim of this study was to detect, characterize, and compare Rickettsia spp. from the fleas of micromammals in areas with different human population densities in Chile. METHODS: The presence of Rickettsia spp. was evaluated by standard polymerase chain reaction (PCR) and sequencing in 1315 fleas collected from 1512 micromammals in 29 locations, with different human population densities in Chile. A generalized linear model (GLM) was used to identify the variables that may explain Rickettsia prevalence in fleas. RESULTS: DNA of Rickettsia spp. was identified in 13.2% (174 of 1315) of fleas tested. Fifteen flea species were found to be Rickettsia-positive. The prevalence of Rickettsia spp. was higher in winter, semi-arid region and natural areas, and the infection levels in fleas varied between species of flea. The prevalence of Rickettsia among flea species ranged between 0-35.1%. Areas of lower human density showed the highest prevalence of Rickettsia. The phylogenetic tree showed two well-differentiated clades with Rickettsia bellii positioned as basal in one clade. The second clade was subdivided into two subclades of species related to Rickettsia of the spotted fever group. CONCLUSIONS: To our knowledge, this is the first report of the occurrence and molecular characterization of Rickettsia spp. in 15 flea species of micromammals in Chile. In this study, fleas were detected carrying Rickettsia DNA with zoonotic potential, mainly in villages and natural areas of Chile. Considering that there are differences in the prevalence of Rickettsia in fleas associated with different factors, more investigations are needed to further understand the ecology of Rickettsia in fleas and their implications for human health.


Sujet(s)
Infestations par les puces/épidémiologie , Rickettsioses/épidémiologie , Rickettsia/isolement et purification , Siphonaptera/microbiologie , Animaux , Chili/épidémiologie , Écologie , Infestations par les puces/parasitologie , Humains , Phylogenèse , Rickettsia/génétique , Rickettsioses/microbiologie , Rodentia
16.
Comp Immunol Microbiol Infect Dis ; 73: 101568, 2020 Dec.
Article de Anglais | MEDLINE | ID: mdl-33120299

RÉSUMÉ

The Neotropical region shows a great diversity of fleas, comprising more than 50 genera. The importance of the study of fleas is linked to their potential role as disease vectors. The aim of this study is to investigate the presence of Rickettsia spp. and Bartonella spp. in Neotropical fleas collected from wild rodents in Southern Brazil. From 350 rodents captured, 30 were parasitized by fleas. A total of 61 fleas belonging to two genera and six different species were collected (Craneopsylla minerva minerva, Polygenis occidentalis occidentalis, Polygenis platensis, Polygenis pradoi, Polygenis rimatus, and Polygenis roberti roberti). In 13 % of fleas of three different species (C. minerva, P. platensis, and P. pradoi) Rickettsia sp. DNA was found. Phylogenetic analysis of concatenated sequences of gltA, htrA, and ompA genes showed that Rickettsia sp. found in rodent fleas (referred as strain Taim) grouped together with Spotted Fever Group Rickettsia. In reference to Bartonella spp., five genotypes were identified in seven fleas of two species (C. minerva and P. platensis) and in five rodent spleens. Also, 207 frozen samples of wild rodents were screened for these pathogens: while none was positive for Rickettsia spp.; five rodent spleens were PCR-positive for Bartonella spp.. Herein, we show the detection of potential novel variants of Bartonella sp. and Rickettsia sp. in fleas collected of wild rodents from Southern Brazil. Further studies are needed to fully characterize these microorganisms, as well as to improve the knowledge on the potential role of Neotropical flea species as diseases vectors.


Sujet(s)
Arvicolinae/parasitologie , Bartonella/isolement et purification , Vecteurs insectes/microbiologie , Rickettsia/isolement et purification , Maladies des rongeurs/parasitologie , Siphonaptera/microbiologie , Animaux , Bartonella/classification , Bartonella/génétique , Infections à Bartonella/microbiologie , Brésil/épidémiologie , Infestations par les puces/parasitologie , Infestations par les puces/médecine vétérinaire , Phylogenèse , Rickettsia/classification , Rickettsia/génétique , Maladies des rongeurs/épidémiologie , Rickettsiose du groupe des fièvres boutonneuses/complications , Rickettsiose du groupe des fièvres boutonneuses/microbiologie , Rickettsiose du groupe des fièvres boutonneuses/médecine vétérinaire
17.
Vet Parasitol Reg Stud Reports ; 21: 100445, 2020 07.
Article de Anglais | MEDLINE | ID: mdl-32862894

RÉSUMÉ

The aim of this study was to detect and identify the presence of Rickettsia in fleas associated with cricetid rodents from northeastern Buenos Aires Province, Argentina. Sixteen fleas belonging to three species of Polygenis were collected from 56 cricetid rodents and analyzed for the presence of Rickettsia performing the conventional polymerase chain reaction (PCR) technique. Only one specimen of Polygenis (Polygenis) axius axius collected from Oxymycterus rufus was positive for Rickettsia felis using the gltA gene, and to ompA gene. This is the first report of R. felis in a Rhopalopsyllidae flea from Argentina, and the first detection of this bacterium in P. (P.) a. axius. Since both, O. rufus and P. (P.) a. axius, are common in areas close to humans, and enzootic cycle of R. felis is not fully understood, the results herein obtained might be of epidemiological importance. Further studies are needed in order to analyze the capacity of the species of Polygenis to transmit R. felis.


Sujet(s)
Arvicolinae , Infestations par les puces/médecine vétérinaire , Rickettsioses/médecine vétérinaire , Rickettsia felis/isolement et purification , Maladies des rongeurs/épidémiologie , Siphonaptera/microbiologie , Animaux , Argentine/épidémiologie , Femelle , Infestations par les puces/épidémiologie , Infestations par les puces/parasitologie , Mâle , Prévalence , Rickettsioses/épidémiologie , Rickettsioses/microbiologie , Maladies des rongeurs/microbiologie , Maladies des rongeurs/parasitologie
18.
Acta Trop ; 212: 105672, 2020 Dec.
Article de Anglais | MEDLINE | ID: mdl-32835672

RÉSUMÉ

The aim of this study was to molecularly survey Bartonella spp. in rodents from the Valdivia Province, Southern Chile and from wild black rat-fleas in Guafo Island, Chilean Patagonia. Thrity-three spleens from synanthropic (Mus musculus, Rattus novergicus and Rattus rattus) and wild (Abrothrix longipilis, Oligoryzomys longicaudatus, Abrothrix sp.) rodents from Valdivia and 39 fleas/flea-pools (Plocopsylla sp. and Nosopsyllus sp.) from R. rattus in Guafo Island were obtained. All samples were screened by high-resolution melting (HRM) real-time PCR for Bartonella ITS locus (190 bp). ITS-Positive samples were further analyzed for two HRM real-time PCR assays targeting Bartonella rpoB (191 bp) and gltA (340 bp) gene fragments. All positive ITS, gltA and rpoB real-time PCR products were purified and sequenced. Bayesian inference trees were built for the gltA and rpoB gene fragments. Bartonella-ITS DNA was detected in 36.3% (12/33) [95% CI (22-53%)] of the tested rodents from Valdivia, being identified in all but O. longicaudatus rodent species captured in this study. ITS DNA was detected in 28% (11/39) [95% CI (16-43%)] of fleas/flea-pools from Guafo Island and identified in both Plocopsylla and Nosopsyllus genera. Sequencing and phylogenic analyses targeting three loci of Bartonella spp. allowed the identification of five genotypes in rodents from Southern Chile, potentially belonging to three different Bartonella spp. Those included Bartonella tribocorum identified from R. rattus, Bartonella rochalimae detected from Abrothix sp., and one novel genotype from uncharacterized Bartonella sp. identified in M. musculus, R. norvegicus, A. longipilis, and Abothrix sp., related to strains previously isolated in Phyllotis sp. from Peru. Additionally, two genotypes of B. tribocorum were identified in fleas from Guafo. In a nutshell, highly diverse and potentially zoonotic Bartonella spp. are described for the first time in wild and synanthropic rodents from Chile, and B. tribocorum was detected in wild back rat fleas from Guafo Island.


Sujet(s)
Bartonella/isolement et purification , Rodentia/microbiologie , Siphonaptera/microbiologie , Animaux , Bartonella/génétique , Chili , Femelle , Génotype , Mâle , Souris , Rats
19.
Med Vet Entomol ; 34(3): 302-308, 2020 09.
Article de Anglais | MEDLINE | ID: mdl-32175623

RÉSUMÉ

Bartonella sp. infection is quite common in free-roaming dogs in many tropical countries. However, limited information is available of the presence of these pathogens in Mexico. The present study looked at prevalence of Bartonella exposure and/or infection in dogs and their fleas in Central Mexico. Blood samples were collected from 31 stray dogs in August 2014 at the municipal pound, Tulancingo, Mexico, as well as fleas on 26 of them. Bartonella seropositivity was 46.9%, including 35.5% for Bartonella henselae, 45% for Bartonella clarridgeiae and 32.2% for Bartonella vinsonii subsp. berkhoffii. Three (9.7%) dogs were polymerase chain reaction (PCR) positive for the Bartonella gltA gene. Partial sequencing of that gene revealed that these three dogs were infected with B. henselae. In total, 86 fleas were collected from 26 dogs (range 1-9 fleas per dog), including 52 Ctenocephalides felis and 34 Ctenocephalides canis. Of 40 pools of fleas (20 pools of C. canis and 20 pools of C. felis), five (12.5%) were PCR positive for the Bartonella sp. gltA gene, including three C. canis pools (five fleas) and two C. felis pools (three fleas). All sequences showed 99.25% to 100% homology with B. henselae Houston I.


Sujet(s)
Infections à Bartonella/médecine vétérinaire , Bartonella henselae/isolement et purification , Bartonella/isolement et purification , Maladies des chiens/épidémiologie , Siphonaptera/microbiologie , Animaux , Infections à Bartonella/épidémiologie , Infections à Bartonella/microbiologie , Maladies des chiens/microbiologie , Chiens , Femelle , Mâle , Mexique/épidémiologie , Réaction de polymérisation en chaîne/médecine vétérinaire , Prévalence
20.
Exp Appl Acarol ; 80(3): 329-338, 2020 Mar.
Article de Anglais | MEDLINE | ID: mdl-31927646

RÉSUMÉ

Ticks and fleas are essential vectors of pathogens that affect humans and animals, and among their hosts, synanthropic animals such as the black-eared opossum, Didelphis aurita, play a role in public health due to their ability to move between urban centers and forested areas in Brazil. This study aimed to assess the ectoparasite fauna of D. aurita, as well as the presence of pathogens and endosymbionts in ticks and fleas. Opossums (n = 58) captured in Tomahawk livetraps were examined for ectoparasites, and their blood sampled for further analysis. Additionally, spleen samples were collected in individuals found dead. Samples were PCR screened for Rickettsia spp., Borrelia spp., Anaplasmataceae, and Babesia spp. Two tick species were morphologically identified as Ixodes loricatus 24/58 (41.4%) and Amblyomma sculptum 1/58 (1.7%). For fleas, Ctenocephalides felis was detected in 60.3% (35/58) of the animals, and Xenopsylla cheopis in 5.2% (3/58). PCR analysis detected Anaplasmataceae DNA in 34% (16/47) of pooled samples of C. felis, and in 66.7% (2/3) pooled samples of X. cheopis. Sequence analysis revealed Wolbachia pipientis symbiont in all positive samples. Tick, blood and spleen samples were all negative for the microorganisms assessed. These findings suggest that these arthropods circulate among wildlife and urban environments, which may implicate in their participation in the cycle of zoonotic pathogens among opossums, humans and companion animals.


Sujet(s)
Didelphis/parasitologie , Infestations par les puces/médecine vétérinaire , Ixodidae/microbiologie , Siphonaptera/microbiologie , Infestations par les tiques/médecine vétérinaire , Anaplasmataceae/isolement et purification , Animaux , Brésil , Wolbachia/isolement et purification
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