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1.
PLoS Negl Trop Dis ; 14(1): e0007519, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31961870

RESUMO

BACKGROUND: Ecological determinants of most emerging vector-borne diseases are understudied, particularly for neglected tropical disease. Moreover, although socioeconomic impacts can have significant downstream effects on human risks to vector-borne diseases via a change in land cover, particularly facilitating the invasion of exotic plants, related studies remains very scarce. Scrub typhus and spotted fever are neglected diseases emerging around the globe and are transmitted by chigger mites and ticks infective of Orientia tsutsugamushi and Rickettsia spp., respectively, with small mammals as the primary hosts of both vectors. METHODOLOGY/PRINCIPAL FINDINGS: We investigated how invasions of the plant Leucaena leucocephala caused by widespread abandonment of farmlands driven by industrialization affected abundance of chiggers and ticks in Penghu Island, Taiwan. We determined ectoparasite abundance by trapping small mammals in three types of habitats (invasion site, agricultural field, human residential) every two months for a year. Based on ectoparasite burdens, invasion sites harbored more chiggers and ticks than the other two habitats. Furthermore, hosts maintained higher burdens of both vectors in early winter and burdens of chiggers were more stable across seasons in invasion sites, suggesting that sites with invasive plants could be a temporary refuge for both vectors and might help mitigate the negative influence of unfavorable climate. Infective rates of O. tsutsugamushi in chiggers and Rickettsia in ticks were also consistently not lower in invasion sites. Top soil temperature and relative humidity were similar across the three habitats, but invasion sites contained more of the rat Rattus losea, on which chiggers and ticks were more engorged than those from the most commonly trapped species (Suncus murinus shrew), indicating that abundance of the host R. losea instead of microclimate might better determine the abundance of both vectors. CONCLUSIONS/SIGNIFICANCE: This study highlights an important but largely neglected issue that socioeconomic change can have unexpected consequences for human health induced particularly by invasive plants, which could become a hotspot for emerging infectious diseases but usually are very hard to be eradicated. In the future, a more comprehensive approach that integrates socio-economics, land use, exotic species, and human health should be considered to fully understand potential emergence of vector-borne diseases.


Assuntos
Fabaceae/parasitologia , Tifo por Ácaros/transmissão , Rickettsiose do Grupo da Febre Maculosa/transmissão , Carrapatos/microbiologia , Trombiculidae/microbiologia , Animais , Vetores Aracnídeos/microbiologia , Vetores Aracnídeos/fisiologia , Ecossistema , Espécies Introduzidas/economia , Orientia tsutsugamushi/fisiologia , Ratos , Rickettsia/fisiologia , Roedores/parasitologia , Tifo por Ácaros/microbiologia , Fatores Socioeconômicos , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Taiwan , Carrapatos/fisiologia
2.
Parasit Vectors ; 12(1): 489, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623642

RESUMO

BACKGROUND: Ticks and tick-borne diseases are a major impediment to livestock production worldwide. Cattle trade and transnational transhumance create risks for the spread of ticks and tick-borne diseases and threaten cattle production in the absence of an effective tick control program. Few studies have been undertaken on cattle ticks in the Central African region; therefore, the need to assess the occurrence and the spatial distribution of tick vectors with the aim of establishing a baseline for monitoring future spread of tick borne-diseases in the region is urgent. RESULTS: A total of 7091 ixodid ticks were collected during a countrywide cross-sectional field survey and identified using morphological criteria. Of these, 4210 (59.4%) ticks were Amblyomma variegatum, 1112 (15.6%) Rhipicephalus (Boophilus) microplus, 708 (10.0%) Rhipicephalus (Boophilus) decoloratus, 28 (0.4%) Rhipicephalus (Boophilus) annulatus, 210 (3.0%) Hyalomma rufipes, 768 (10.8%) Hyalomma truncatum, and 19 (0.3%) Rhipicephalus sanguineus. Three ticks of the genus Hyalomma spp. and 33 of the genus Rhipicephalus spp. were not identified to the species level. Cytochrome c oxidase subunit 1 (cox1) gene sequencing supported the data from morphological examination and led to identification of three additional species, namely Hyalomma dromedarii, Rhipicephalus sulcatus and Rhipicephalus pusillus. The finding of the invasive tick species R. microplus in such large numbers and the apparent displacement of the indigenous R. decoloratus is highly significant since R. microplus is a highly efficient vector of Babesia bovis. CONCLUSIONS: This study reports the occurrence and current geographical distribution of important tick vectors associated with cattle in Cameroon. It appears that R. microplus is now well established and may be displacing native Rhipicephalus (Boophilus) species, such as R. decoloratus. This calls for an urgent response to safeguard the livestock sector in western central Africa.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Infestações por Carrapato/veterinária , Carrapatos/fisiologia , Agricultura , Animais , Camarões/epidemiologia , Bovinos , Sequência Consenso , Estudos Transversais , Ciclo-Oxigenase 1/genética , Demografia , Feminino , Masculino , Filogenia , Prevalência , Alinhamento de Sequência/veterinária , Razão de Masculinidade , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária , Carrapatos/classificação , Carrapatos/crescimento & desenvolvimento
4.
Emerg Microbes Infect ; 8(1): 1122-1125, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31347462

RESUMO

The Xinjiang Uygur Autonomous Region locating in Northwest of China was not considered the epidemic area of severe fever with thrombocytopenia syndrome (SFTS). Here we report the first laboratory-confirmed SFTS case that a female patient had tick bite in Xinjiang and illness onset after returning to Hainan Province. Laboratory tests identified SFTS virus (SFTSV) infection, and the virus was isolated from the patient's serum sample. Furthermore, SFTSV prevalence among tick groups was identified, and IgM response to SFTSV from febrile patients was identified. The findings suggested that there have been risks of SFTSV infection due to exposure to ticks in Xinjiang.


Assuntos
Infecções por Bunyaviridae/diagnóstico , Phlebovirus/isolamento & purificação , Trombocitopenia/diagnóstico , Animais , Infecções por Bunyaviridae/sangue , Infecções por Bunyaviridae/transmissão , Infecções por Bunyaviridae/virologia , China , Feminino , Humanos , Pessoa de Meia-Idade , Phlebovirus/classificação , Phlebovirus/genética , Phlebovirus/fisiologia , Filogenia , Trombocitopenia/sangue , Trombocitopenia/virologia , Carrapatos/fisiologia , Carrapatos/virologia , Viagem
5.
Ann Agric Environ Med ; 26(2): 217-221, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31232048

RESUMO

INTRODUCTION AND OBJECTIVE: The incidence of Lyme borreliosis (LB) is increasing in many countries in Europe, including Poland and Slovakia. The aim of the study was to analyze the exposure to tick bites and undertaking LB prevention activities among students of medical fields of studies in Poland (PL) and Slovakia (SK). MATERIAL AND METHODS: The study was conducted among 611 students from Poland (296 students) and Slovakia (315 students). The applied research tool was the questionnaire. It consisted of questions about exposure to ticks (occurrence of an episode of tick bites, bite site, methods used for tick removal) and the frequency of undertaking preventive actions (using repellents, checking the body after returning from green areas). Pearson Chi-square statistics were calculated to assess significant differences between students from the study countries PL/SK and gender in each country. RESULTS: Among surveyed students the episode of a tick bite was reported by 352 persons (57.6%). Students from PL most frequently removed ticks with tweezers with a swift, steady movement (26.6%), while students from SK removed the tick by applying a fatty substance so that it would come off by itself (30.1%). Most of the surveyed students, being outdoors, did not apply ticks repellents (34.7%) or used them rarely (48.9%). At the same time, 49.4% of students stated that they always checked the body to search for any attached tick after returning from green areas. CONCLUSIONS: Considering the fact that the surveyed people were the students of medical fields of studies, and in the future became qualified medical personnel, the frequency of using the analyzed methods of prophylaxis of LB appears to be too small. The results obtained can help in the education of students of medical fields.


Assuntos
Doença de Lyme/prevenção & controle , Picadas de Carrapatos/prevenção & controle , Adulto , Animais , Feminino , Humanos , Incidência , Doença de Lyme/epidemiologia , Masculino , Polônia , Eslováquia/epidemiologia , Estudantes/estatística & dados numéricos , Picadas de Carrapatos/epidemiologia , Carrapatos/fisiologia , Adulto Jovem
6.
Emerg Microbes Infect ; 8(1): 959-961, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244397

RESUMO

Human babesiosis is an important tick-borne infectious disease. We investigated human babesiosis in the Gansu province and found that it is prevalent in this area with a prevalence of 1.3%. Results of gene sequencings indicate that 1.3% of patients were positive for Babesia divergens. This initial report of human B. divergens infections in Gansu Province should raise awareness of human babesiosis.


Assuntos
Babesia/isolamento & purificação , Babesiose/parasitologia , Mordeduras e Picadas/parasitologia , Adulto , Animais , Babesia/classificação , Babesia/genética , Babesiose/transmissão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Tibet , Carrapatos/parasitologia , Carrapatos/fisiologia
7.
PLoS Negl Trop Dis ; 13(5): e0007003, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31067231

RESUMO

The present study investigated the presence of endo- and ecto-parasites, and vector-borne pathogens, in dogs from four islands of Greece. A total of 200 (123 owned and 77 sheltered) dogs were examined with different microscopic, serological and molecular methods. Of the examined dogs, 130 (65%) were positive for one or more parasites and/or vector-borne pathogens. The most common zoonotic intestinal helminths recorded were Ancylostomatidae (12.5%) and Toxocara canis (3.5%). Ninety-three dogs (46.5%) seroreacted to Rickettsia conorii. Twenty-two (11%) of them were also PCR positive and 7 (3.5%) showed corpuscles suggestive of Rickettsia spp. on the blood smears. Nineteen dogs (9.5%) were seropositive for Ehrlichia canis, three of them being also PCR positive. Dogs positive for Anaplasma phagocytophilum-Anaplasma platys (1%), Dirofilaria immitis (0.5%) and Babesia canis (0.5%) were also found. Fleas and ticks were recorded in 53 (26.5%) and 50 (25%) dogs, respectively, and all specimens were identified as Ctenocephalides felis felis and Rhipicephalus sanguineus sensu lato. Binary multiple univariate Generalized Linear Models were used to investigate factors and clinical signs related to the recorded positivity, while the association of specific signs with the pathogens was evaluated using tests of independence. Knowledge of occurrence and impact of zoonotic parasites and vector-borne pathogens in dog populations is crucial to prevent the infection in animals and people, and to control the risk of spreading of these pathogens in endemic and non-endemic areas.


Assuntos
Vetores de Doenças , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Infestações por Pulgas/veterinária , Parasitos/isolamento & purificação , Rickettsia/isolamento & purificação , Zoonoses/microbiologia , Zoonoses/parasitologia , Animais , Doenças do Cão/epidemiologia , Cães , Feminino , Infestações por Pulgas/parasitologia , Grécia/epidemiologia , Humanos , Masculino , Parasitos/classificação , Parasitos/genética , Parasitos/fisiologia , Rickettsia/classificação , Rickettsia/genética , Rickettsia/fisiologia , Sifonápteros/classificação , Sifonápteros/genética , Sifonápteros/fisiologia , Carrapatos/classificação , Carrapatos/genética , Carrapatos/fisiologia , Zoonoses/transmissão
8.
Parasit Vectors ; 12(1): 235, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092286

RESUMO

BACKGROUND: Ticks are blood-sucking arthropods that can transmit diseases to humans and animals. These arthropods are the second most important vectors of pathogens. MicroRNAs are a class of conserved small noncoding RNAs that play regulatory roles in gene expression at the post-transcriptional level. Molting is an important biological process in arthropods. Research on the molting process is important for understanding tick physiology and control. METHODS: Dual-luciferase reporter assays were used to assess the role of miRNA let-7 in ecdysteroid receptor (ECR) biology. The expression levels of ECR and let-7 were measured by real-time qPCR before and after tick molting. To explore the function of let-7 and ECR, we performed overexpression and knocking down of let-7 and RNAi of ECR in tick nymphs. The biological function of let-7 in molting was explored by injecting nymphs, ten days after engorgement, with let-7 agomir for overexpression and let-7 antagomir for knocking down. The rate of molting was then determined. ECR dsRNA was injected into ticks to evaluate the function of ECR by gene silencing. The expression of ECR and let-7 was measured using RT-qPCR. All data were analyzed using GraphPad Prism v.6. RESULTS: The results of the luciferase assay using a eukaryotic expression system revealed that ECR was a natural target of let-7. Let-7 overexpressed by agomir affected the rate of molting (P < 0.01) and the period of molting (P < 0.01). Let-7 antagomir for knockdown affected the period of molting (P < 0.01), but there was no effect on the rate of molting (P = 0.27). ECR dsRNA gene silencing significantly affected the rate of molting (P < 0.05). CONCLUSIONS: This study demonstrated that let-7 can regulate the expression of ECR and that let-7 can affect molting in ticks. Our results help to understand the regulation of let-7 by 20-hydroxyecdysone (20E) and will provide a reference for functional analysis studies of microRNAs in ticks.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/genética , Muda/genética , Receptores de Esteroides/genética , Carrapatos/genética , Animais , Ecdisterona/genética , Ninfa/genética , Ninfa/fisiologia , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Carrapatos/fisiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-31139576

RESUMO

Francisella tularensis, the causative agent of the zoonotic disease tularemia, is characterized by high morbidity and mortality rates in over 190 different mammalian species, including humans. Based on its low infectious dose, multiple routes of infection, and ability to induce rapid and lethal disease, F. tularensis has been recognized as a severe public health threat-being designated as a NIH Category A Priority Pathogen and a CDC Tier 1 Select Agent. Despite concerns over its use as a bioweapon, most U.S. tularemia cases are tick-mediated and ticks are believed to be the major environmental reservoir for F. tularensis in the U.S. The American dog tick (Dermacentor variabilis) has been reported to be the primary tick vector for F. tularensis, but the lone star tick (Amblyomma americanum) and other tick species also have been shown to harbor F. tularensis. This review highlights what is known, not known, and is debated, about the roles of different tick species as environmental reservoirs and transmission vectors for a variety of F. tularensis genotypes/strains.


Assuntos
Reservatórios de Doenças/microbiologia , Francisella tularensis/fisiologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/transmissão , Carrapatos/microbiologia , Carrapatos/fisiologia , Tularemia/microbiologia , Tularemia/transmissão , Animais , Dermacentor , Doenças do Cão/microbiologia , Doenças do Cão/transmissão , Cães , Genótipo , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Ixodidae , Simbiose , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/classificação , Tularemia/epidemiologia , Estados Unidos
10.
Parasit Vectors ; 12(1): 189, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036065

RESUMO

BACKGROUND: Tick-borne diseases have been increasing at the local, national, and global levels. Researchers studying ticks and tick-borne diseases need a thorough knowledge of the pathogens, vectors, and epidemiology of disease spread. Both active and passive surveillance approaches are typically used to estimate tick population size and risk of tick encounter. Our data consists of a composite of active and long-term passive surveillance, which has provided insight into spatial variability and temporal dynamics of ectoparasite communities and identified rarer tick species. We present a retrospective analysis on compiled data of ticks from Pennsylvania over the last 117 years. METHODS: We compiled data from ticks collected during tick surveillance research, and from citizen-based submissions. The majority of the specimens were submitted by citizens. However, a subset of the data was collected through active methods (flagging or dragging, or removal of ticks from wildlife). We analyzed all data from 1900-2017 for tick community composition, host associations, and spatio-temporal dynamics. RESULTS: In total there were 4491 submission lots consisting of 7132 tick specimens. Twenty-four different species were identified, with the large proportion of submissions represented by five tick species. We observed a shift in tick community composition in which the dominant species of tick (Ixodes cookei) was overtaken in abundance by Dermacentor variabilis in the early 1990s and then replaced in abundance by I. scapularis. We analyzed host data and identified overlaps in host range amongst tick species. CONCLUSIONS: We highlight the importance of long-term passive tick surveillance in investigating the ecology of both common and rare tick species. Information on the geographical distribution, host-association, and seasonality of the tick community can help researchers and health-officials to identify high-risk areas.


Assuntos
Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/fisiologia , Animais , Animais Selvagens/parasitologia , Dermacentor/fisiologia , Monitoramento Epidemiológico , História do Século XX , História do Século XXI , Humanos , Ixodes/fisiologia , Pennsylvania/epidemiologia , Estudos Retrospectivos , Análise Espacial , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/história , Doenças Transmitidas por Carrapatos/transmissão
11.
Ticks Tick Borne Dis ; 10(5): 981-986, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31109835

RESUMO

Capybaras (Hydrochoerus hydrochaeris Linnaeus, 1766) (Rodentia: Caviidae) are important hosts of Amblyomma ticks (Acari: Ixodidae), which in turn can transmit rickettsiae to humans and animals. However, there is a scarcity of studies about the tick fauna and rickettsial infection in the Amazon region. The present study evaluated rickettsial infection in capybaras and ticks in different areas of the municipality of Rio Branco, state of Acre, in the Western Brazilian Amazon, where rickettsiosis has never been reported. Blood sera from 43 capybaras from four localities in Rio Branco were tested by indirect immunofluorescence assay using Rickettsia rickettsii antigens. Ticks were collected from capybaras and from vegetation as well. Ticks were taxonomically identified to the species level and some of them were tested by PCR, targeting a fragment of the rickettsial gltA gene. Additionally, ticks were tested for bacteria from the genus Borrelia and family Anaplasmatacae. All capybaras submitted to the serological examination were considered non-reactive to R. rickettsii. A total of 410 ticks were collected directly from the capybaras. Amblyomma dubitatum Neumann, 1899 was the most abundant species (82.4%), followed by Amblyomma naponense (Packard, 1869) (14.3%), Amblyomma humerale Koch, 1844 (0.7%), Amblyomma pacae Aragão, 1911 (0.4%), Amblyomma rotundatum Koch 1844 (0.2%) and Amblyomma sp. (1.7%). From the environment 262 ticks were collected: Rhipicephalus microplus (Canestrini, 1888) (88.9%), Dermacentor nitens Neumann, 1897 (9.9%), Amblyomma varium Koch, 1844 (0.7%) and A. rotundatum (0.3%). With the exception of A. humerale, A. rotundatum and R. microplus, all other species are reported here for the first time in the state. Some of the ticks sampled (N = 317) were tested by molecular methods for infection by Rickettsia spp. Rickettsia bellii was identified infecting A. dubitatum and A. rotundatum, while Rickettsia amblyommatis only was found infecting A. humerale and Rickettsia sp. strain Tapirapé was found in A. naponense. This is the first detection of R. bellii and Rickettsia sp. strain Tapirapé in Acre. No Borrelia or Anaplasmataceae were found in the tested ticks. These results add relevant knowledge about the Rickettsia spp. and the acarological fauna in the region of the Western Amazon, and are essential for the maintenance of vigilance about possible pathogens that occur in the state and determination of the risks that they pose to humans and animals that inhabit the region.


Assuntos
Doenças dos Roedores/epidemiologia , Roedores , Rickettsiose do Grupo da Febre Maculosa/veterinária , Infestações por Carrapato/veterinária , Carrapatos/microbiologia , Carrapatos/fisiologia , Anaplasmataceae/isolamento & purificação , Animais , Antígenos de Bactérias/análise , Borrelia/isolamento & purificação , Brasil/epidemiologia , Feminino , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Rickettsia/isolamento & purificação , Rickettsia rickettsii/isolamento & purificação , Doenças dos Roedores/microbiologia , Doenças dos Roedores/parasitologia , Rickettsiose do Grupo da Febre Maculosa/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Carrapatos/classificação
12.
Sci Total Environ ; 670: 941-949, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30921726

RESUMO

Green spaces in the city are important for human wellbeing, but are also zones in which humans can become infected with zoonotic diseases. Therefore, there is a need to understand how infection risk is related to green space characteristics, wildlife communities and connectivity with rural areas hosting reservoir populations of hosts. Our hypothesis is that wildlife hosts in urban green spaces, and thereby the prevalence of questing ticks and their Lyme disease causing pathogens (Borrelia burgdorferi s.l.), can be partly predicted based on green space characteristics as well as measures of connectivity to known source areas. We sampled ticks in twenty-two green spaces during Spring (2014 and 2016) and Autumn 2016, located along an urbanization gradient in Antwerp (Belgium). More than 18,000 m2 was sampled, with tick densities ranging from 0 to 386 individuals/100 m2. We estimated connectivity using the least-cost algorithm as either the cost distance to the nearest green space, or to a known population of roe deer (Capreolus capreolus), known to be an important tick propagation host. Both connectivity measures turned out to be correlated, reflecting a gradient in green space isolation from the periphery to the urban center. In 87% of plots where ticks were trapped, at least one Borrelia-infected tick was found. The overall Borrelia-prevalence in nymphs was 17.8%, in adults 32.6%. Density of infected ticks decreased with urbanization and increased with connectivity. Nymphs in larger green spaces were more likely to be infected. While density and infection prevalence for adults increased with the amount of neighboring agricultural land, the larval density and nymphal infection prevalence decreased. Interestingly, the proportion of Borrelia genospecies associated with birds or mammals was comparable in rural and (sub)urban areas (bird/mammal: 0.38), suggesting that even in small green spaces Borrelia infections can persist in local host populations.


Assuntos
Conservação dos Recursos Naturais/métodos , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/fisiologia , Animais , Bélgica/epidemiologia , Borrelia burgdorferi , Cidades/estatística & dados numéricos , Cervos , Ecossistema , Florestas , Humanos , Doença de Lyme/epidemiologia , Urbanização/tendências , Zoonoses
13.
Exp Appl Acarol ; 77(2): 241-251, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30771037

RESUMO

Seasonal bird (Aves) migration between breeding and wintering areas, often located on different continents, can facilitate the spreading of tick species (Acari: Ixodida) and of tick-borne pathogens. The aim of the study was to analyse the occurrence of ticks dispersed by birds migrating along the Polish Baltic coast during spring and autumn migration. Field research was conducted at the bird ringing station in Wicie, located on the middle of the Polish Baltic coast, in 2011 and 2012 during spring and autumn migration. A total of 2657 birds from 45 species was examined. The most common species inspected were European robin (Erithacus rubecula) (63.3%), song thrush (Turdus philomelos) (5.13%), and goldcrest (Regulus regulus) (4.5%). Overall, 3129 ticks belonging to six species were collected: Ixodes ricinus (1650 larvae, 1390 nymphs and 1 male), Ixodes frontalis (20 larvae, 20 nymphs), Ixodes arboricola (35 larvae), Dermacentor reticulatus (1 larva), and Haemaphysalis punctata (1 nymph). Ten larvae and one nymph could only be identified to the genus level Ixodes. Ticks were located on various parts of the head: on the corner of the beak (75.0%), near the eyes (14.6%), on the chin (4.4%), near the ears (4.4%), on the neck (1.1%), and in the beak (0.5%). The overall tick prevalence was 40.5%. The highest prevalence was for bird species feeding on the ground, covering a medium distance to wintering grounds and migrating at night. Statistically significant differences between the number of ticks and the sex of the host species were detected in blackbirds: males carried more parasites than females, both, during spring and autumn migration. The fact that I. ricinus and other ticks parasitize birds migrating through Poland extends the possibility of the spread of tick-borne diseases.


Assuntos
Migração Animal , Aves Canoras , Infestações por Carrapato/veterinária , Carrapatos/fisiologia , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Feminino , Larva/classificação , Larva/fisiologia , Masculino , Ninfa/classificação , Ninfa/fisiologia , Polônia/epidemiologia , Prevalência , Estações do Ano , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Carrapatos/classificação , Carrapatos/crescimento & desenvolvimento
14.
Ticks Tick Borne Dis ; 10(3): 564-567, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30712995

RESUMO

The southern cattle tick, Rhipicephalus (Boophilus) microplus, is an economically important tick that parasitises cattle and is found on other host species if they graze with cattle. The R. (B.) microplus is a highly adapted tick species prevalent in tropical and subtropical regions of the world. In Africa, it has expanded its range and was reported to supersede the native tick, R. (B.) decoloratus. The objective of the study was to determine the distribution of R. (B.) microplus under different ecological zones in the western-central regions of Eastern Cape Province. Engorged adult blue ticks were collected monthly from 360 randomly selected cattle and free living ticks from six replicate drags of the vegetation over a period of 1 year at Bedford Dry Grassland (BDG), Kowie Thicket (KT) and Bhisho Thornveld (BT). A special attention was paid to the lower perineum, neck, dewlap and ventral body parts which are the preferred sites for blue ticks during sampling. In this study, 9 species of ticks which grouped under 5 genera were identified. The identified species of ticks were Amblyomma hebraeum, Haemaphysalis elliptica, Hyalomma rufipes, Ixodes pilosus, R. (B.) decoloratus, R. appendiculatus, R. evertsi evertsi, R. follis and R. simus. Only adult R. (B.) decoloratus (n = 8090) ticks were collected from cattle between April 2016 and March 2017. A total of 4382 females and 3708 males of R. (B.) decoloratus were recovered during the survey. Of the ticks (n = 2885) collected from the vegetation, R. (B.) decoloratus was the most abundant species with a relative prevalence of 58.16%, followed by R. appendiculatus (18.37%) and R. evertsi evertsi (16.90%). Least abundant ticks were H. rufipes (2.98%), A. hebraeum (2.46%), H. elliptica (0.38%), R. follis (0.34%), I. pilosus (0.24%) and R. simus (0.17%). The distribution of R. (B.) decoloratus ticks differ significantly (P < 0.05) among the vegetation types. Significantly more (P < 0.05) engorged R. (B.) decoloratus were collected in KT during summer season (1.39 ± 0.063 females and 1.30 ± 0.063 males) compared to other vegetation types. The R. (B.) decoloratus larvae were significantly higher (P < 0.05) in BT (20.56±1.154) and KT (18.50±1.154) vegetation types during the spring season. R. (B.) microplus was not found in the present study, signifying that it is not yet established in western-central regions of the Eastern Cape Province and as such, continuous monitoring would be advisable.


Assuntos
Distribuição Animal , Doenças dos Bovinos/epidemiologia , Rhipicephalus/fisiologia , Infestações por Carrapato/veterinária , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Ecologia , Feminino , Pradaria , Ixodes/fisiologia , Ixodidae/fisiologia , Masculino , Estações do Ano , África do Sul/epidemiologia , Infestações por Carrapato/epidemiologia , Carrapatos/fisiologia
15.
Mol Immunol ; 107: 106-114, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30711907

RESUMO

Several studies have shown that cytotoxic T lymphocytes (CTL) require CD4 + Th1 epitopes to generate strong immune responses to intracellular pathogens. However, not much is known about Ehrlichia ruminantium epitopes, particularly those that can be considered potential candidates for inclusion in a multi-epitope vaccine. In order to identify CD4+ Th1 epitopes that induce IFNγ, a number of proteins previously identified as immunogenic were first screened to determine if they induce cellular immunity in tick infected immune sheep PBMC. Significant IFN-γ production and other Th1 cytokines were evident for 10 recombinant proteins in all sheep tested. Secondly, peptides (n = 246) derived from the top 10 E. ruminantium vaccine candidate proteins were assayed using enzyme linked immunospot (ELISPOT) assay, quantitative real-time PCR and flow cytometry. Of the 246 peptides, 23 peptides, Erum0660 (p0660-42), Erum1150 (p1150-18, p1150-19), Erum2540 (p2540-6, p2540-16, p2540-19, p2540-20, p2540-21), Erum5420 (p5420-13, p5420-14), Erum7140 (p7140-6, p7140-7, p7140-12, p7140-13, p7140-20), Erum7320 (p7320-8, p7320-9, p7320-21), Erum7350 (p7350-9), Erum7360 (p7360-8), Erum7620 (p7620-2, p7620-12) and Erum8010 (p8010-8) were identified that stimulate the best and different cell mediated immune responses. Amino acid sequences of these peptides except for p7140-12, p7140-13, p7140-20, and p7350-9 were conserved between 13 different local strains. These peptides could efficiently induce memory CD4+ T cells to rapidly proliferate and significantly increase IFN-γ production in immune sheep PBMC. The upregulation of pro-inflammatory cytokines, which include, IL-1α, IL-2, IL-12p40, TNF-α, IFN-γ, inducible nitric oxide synthase (iNOS) and granulocyte-macrophage colony stimulating factor (GM-CSF) was also detected. Our results show that these peptides could serve as promising candidates for a multi-epitope vaccine against E. ruminantium.


Assuntos
Vacinas Bacterianas/imunologia , Sequência Conservada , Ehrlichia ruminantium/imunologia , Epitopos/imunologia , Ativação Linfocitária/imunologia , Células Th1/imunologia , Animais , Citocinas/genética , Citocinas/metabolismo , Interferon gama/metabolismo , Leucócitos Mononucleares/metabolismo , Peptídeos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Ovinos/imunologia , Ovinos/microbiologia , Ovinos/parasitologia , Carrapatos/fisiologia
16.
Infect Immun ; 87(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30642902

RESUMO

The global public health impact of relapsing fever (RF) spirochetosis is significant, since the pathogens exist on five of seven continents. The hallmark sign of infection is episodic fever and the greatest threat is to the unborn. With the goal of better understanding the specificity of B-cell responses and the role of immune responses in pathogenicity, we infected rhesus macaques with Borrelia turicatae (a new world RF spirochete species) by tick bite and monitored the immune responses generated in response to the pathogen. Specifically, we evaluated inflammatory mediator induction by the pathogen, host antibody responses to specific antigens, and peripheral lymphocyte population dynamics. Our results indicate that B. turicatae elicits from peripheral blood cells key inflammatory response mediators (interleukin-1ß and tumor necrosis factor alpha), which are associated with preterm abortion. Moreover, a global decline in peripheral B-cell populations was observed in all animals at 14 days postinfection. Serological responses were also evaluated to assess the antigenicity of three surface proteins: BipA, BrpA, and Bta112. Interestingly, a distinction was observed between antibodies generated in nonhuman primates and mice. Our results provide support for the nonhuman primate model not only in studies of prenatal pathogenesis but also for diagnostic and vaccine antigen identification and testing.


Assuntos
Anticorpos Antibacterianos/imunologia , Borrelia/fisiologia , Borrelia/patogenicidade , Febre Recorrente/imunologia , Febre Recorrente/microbiologia , Animais , Formação de Anticorpos , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Borrelia/genética , Borrelia/imunologia , Modelos Animais de Doenças , Humanos , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Macaca mulatta/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Febre Recorrente/diagnóstico , Febre Recorrente/transmissão , Carrapatos/microbiologia , Carrapatos/fisiologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Virulência
17.
Ticks Tick Borne Dis ; 10(1): 156-161, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30337264

RESUMO

BACKGROUND: It is heavily debated whether tick-borne infections cause chronic subjective health complaints. If the hypothesis of a major causal connection is true, one would expect to find more subjective health complaints in a population with high exposure to ticks than in a population with less exposure. In the current study we aimed to assess somatic symptoms and fatigue in a Norwegian population with high exposure to ticks, compare our findings to normative data, and assess predictors of somatic symptom load. MATERIAL AND METHODS: All individuals aged 18-69 years with residential address in Søgne municipality in southern Norway were in the period June 2015 to June 2016 invited to participate in the study. Somatic symptoms were assessed by the Patient Health Questionnaire-15 (PHQ-15) and fatigue by the Fatigue Severity Scale (FSS). A multivariable regression analysis was performed to assess predictors of somatic symptom load. RESULTS: Out of 7424 invited individuals, 2971 (40.0%) returned the questionnaire. 85.1% of 2950 responders reported exposure to tick-bite. PHQ-15 mean sum score was 5.3, and 16.5% reported moderate to severe somatic symptom load (i.e. ≥ 10). FSS mean score was 3.2, and 29.8% scored above the cut-off value for fatigue (i.e. ≥ 4.0). All gender and age groups in our study population had equal or lower mean sum score on PHQ-15 than reported in Swedish normative data, and lower mean score on FSS than reported in Norwegian normative data. In multivariable regression the following factors were associated with higher somatic symptom load (listed in order of descending beta coefficient): Anxiety and depression, number of other diseases, female gender, younger age, recruitment when visiting general practitioner's office, ≤ 6 years education after primary school, tick-bite earlier in life, erythema migrans earlier in life, less physical activity, and modern health worries. CONCLUSION: The study population reported high exposure to tick-bites, but less or equal level of somatic symptoms and less fatigue than found in normative data. There was a weak association between somatic symptom load and exposure to tick-bite and erythema migrans, possibly related to selection bias. Our findings do not support the hypothesis of a major causal connection between tick-borne infections and subjective health complaints.


Assuntos
Eritema Migrans Crônico/epidemiologia , Fadiga/epidemiologia , Sintomas Inexplicáveis , Picadas de Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/fisiologia , Adolescente , Adulto , Idoso , Animais , Eritema Migrans Crônico/etiologia , Fadiga/etiologia , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Noruega/epidemiologia , Análise de Regressão , Inquéritos e Questionários , Picadas de Carrapatos/complicações , Doenças Transmitidas por Carrapatos/complicações , Adulto Jovem
18.
Ann Parasitol ; 65(4): 411­416, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32191989

RESUMO

This study investigated the ectoparasites of the Nile Rat, Arvicanthis niloticus in Shendi area, River Nile State, Sudan. Eighty nine A. niloticus were collected for the first time from the horticultural fields of Shendi, between January to June 2018, and their entire fur was combed thoroughly, using a fine-tooth comb. Any removed ectoparasites were relaxed, mounted and examined under a microscope for morphological identification. Forty two (47.2%) of the collected rats was found infested, with an overall mean intensity of 13.4 (range 2­67) ectoparasites per an infested rat; 10 different species of ectoparasites were identified, including: 2 species of flea ­ Xenopsylla cheopis, Leptopsylla segnis; 3 species of louse ­ Polyplax spinulosa, P. abyssinica, P. serrata; a species of tick ­ Rhipicephalus sp.; 4 species of mite ­ Laelaps agilis, L. nuttalli, Ornitonyssus bacoti, Dermanyssuss gallinae. The most prevalent ectoparasite found was the flea Xenopsylla cheopis, 23.6%, followed by the mite Laelaps nuttalli, 10.1%, while the least was the mite Ornitonyssus bacoti, 1.1%. Significantly higher prevalence and intensity of infestation was found among male rats. Likewise, older rats significantly harbored a higher prevalence and intensity of infestation.


Assuntos
Ectoparasitoses , Murinae , Animais , Artrópodes/classificação , Artrópodes/fisiologia , Ectoparasitoses/parasitologia , Feminino , Masculino , Ácaros/fisiologia , Murinae/parasitologia , Ftirápteros/fisiologia , Ratos , Sifonápteros/fisiologia , Sudão , Carrapatos/fisiologia
19.
Exp Appl Acarol ; 76(4): 523-535, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30443697

RESUMO

We report tick infestations and rickettsial detection in ticks infesting free-living wild mammals (Monodelphis domestica, Tolypeutes tricinctus, Thrichomys inermis and Kerodon rupestris) captured in the Caatinga ecoregion of Bahia state, northeastern Brazil, during September to December 2016. Overall, 117 ticks (61 larvae, 25 nymphs, 25 males, 6 females) belonging to two genera, and at least three species were collected: Amblyomma auricularium, Amblyomma parvum, Amblyomma sp., Ornithodoros rietcorreai and an unidentified Ornithodoros sp. We provide new host records to the rodent T. inermis parasitized by larva and nymphs of A. auricularium and to the marsupial M. domestica infested by larvae of A. auricularium. Furthermore, we describe new tick-host association for larvae of O. rietcorreai on the rodents K. rupestris and T. inermis. Concerning tick-Rickettsia associations, we detected Rickettsia amblyommatis and an uncharacterized species of Rickettsia belonging to the spotted fever group (SFG) in both A. auricularium and A. parvum. Additionally, 'Candidatus Rickettsia andeanae' was detected in A. parvum as well.


Assuntos
Tatus , Gambás , Rickettsia/isolamento & purificação , Doenças dos Roedores/parasitologia , Infestações por Carrapato/veterinária , Carrapatos/microbiologia , Carrapatos/fisiologia , Animais , Brasil , Interações Hospedeiro-Parasita , Ixodidae/crescimento & desenvolvimento , Ixodidae/microbiologia , Ixodidae/fisiologia , Larva/crescimento & desenvolvimento , Larva/microbiologia , Larva/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Ninfa/fisiologia , Ornithodoros/crescimento & desenvolvimento , Ornithodoros/microbiologia , Ornithodoros/fisiologia , Infestações por Carrapato/parasitologia , Carrapatos/crescimento & desenvolvimento
20.
Vet Parasitol ; 263: 5-9, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30389024

RESUMO

Rhipicephalus (Boophilus) microplus is one of the most important ectoparasites in cattle breeding worldwide, causing direct and indirect losses to animals and producers. Chemical acaricides are utilized in the control of cattle tick and the increase in the development of resistance by ectoparasites makes new alternative necessary. Therefore, research studies have been carried out using bioactive molecules that are quickly degraded and that reduce poisoning to appliers and non-target organisms, environmental contamination and development of resistance. Thus, this study aimed to isolate piperovatine from the roots of Piper corcovadensis, a native species to Brazil, and to evaluate the larvicidal activity against Rhipicephalus (Boophilus) microplus by larval packet test and in ex situ in an open environment. Piperovatine was isolated by classical column chromatography, and identified by 1H and 13C NMR. The lethal concentration (LC) of piperovatine that killed 50% (LC50) and 99% (LC99) of the larvae was determined by Probit analysis. The results indicated LC50 5.17 and LC99 25.41 µg/mL. LC99 was tested in ex situ in an open environment, and an efficiency of 96.63% was found, indicating that piperovatine kept the larvicidal action determined in in vitro test and in open environment. Therefore, this study shows new perspectives to develop products that can be applied in natural conditions to control this ectoparasite.


Assuntos
Acaricidas/administração & dosagem , Ectoparasitoses/veterinária , Larva/efeitos dos fármacos , Ácido Sórbico/análogos & derivados , Acaricidas/química , Acaricidas/isolamento & purificação , Animais , Produtos Biológicos/administração & dosagem , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/epidemiologia , Descoberta de Drogas , Ectoparasitoses/tratamento farmacológico , Ectoparasitoses/epidemiologia , Feminino , Piper/anatomia & histologia , Piper/química , Ácido Sórbico/administração & dosagem , Ácido Sórbico/química , Ácido Sórbico/isolamento & purificação , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/veterinária , Carrapatos/efeitos dos fármacos , Carrapatos/fisiologia
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