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1.
BMC Infect Dis ; 20(1): 34, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931734

RESUMO

BACKGROUND: Impact of climate change on tick-borne encephalitis (TBE) prevalence in the tick-host enzootic cycle in a given region depends on how the region-specific climate change patterns influence tick population development processes and tick-borne encephalitis virus (TBEV) transmission dynamics involving both systemic and co-feeding transmission routes. Predicting the transmission risk of TBEV in the enzootic cycle with projected climate conditions is essential for planning public health interventions including vaccination programs to mitigate the TBE incidence in the inhabitants and travelers. We have previously developed and validated a mathematical model for retroactive analysis of weather fluctuation on TBE prevalence in Hungary, and we aim to show in this research that this model provides an effective tool for projecting TBEV transmission risk in the enzootic cycle. METHODS: Using the established model of TBEV transmission and the climate predictions of the Vas county in western Hungary in 2021-2050 and 2071-2100, we quantify the risk of TBEV transmission using a series of summative indices - the basic reproduction number, the duration of infestation, the stage-specific tick densities, and the accumulated (tick) infections due to co-feeding transmission. We also measure the significance of co-feeding transmission by observing the cumulative number of new transmissions through the non-systemic transmission route. RESULTS: The transmission potential and the risk in the study site are expected to increase along with the increase of the temperature in 2021-2050 and 2071-2100. This increase will be facilitated by the expected extension of the tick questing season and the increase of the numbers of susceptible ticks (larval and nymphal) and the number of infected nymphal ticks co-feeding on the same hosts, leading to compounded increase of infections through the non-systemic transmission. CONCLUSIONS: The developed mathematical model provides an effective tool for predicting TBE prevalence in the tick-host enzootic cycle, by integrating climate projection with emerging knowledge about the region-specific tick ecological and pathogen enzootic processes (through model parametrization fitting to historical data). Model projects increasing co-feeding transmission and prevalence of TBEV in a recognized TBE endemic region, so human risk of TBEV infection is likely increasing unless public health interventions are enhanced.


Assuntos
Mudança Climática , Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/transmissão , Ixodes/virologia , Animais , Encefalite Transmitida por Carrapatos/virologia , Doenças Endêmicas , Humanos , Hungria/epidemiologia , Incidência , Ixodes/fisiologia , Larva/virologia , Modelos Teóricos , Ninfa/virologia , Prevalência , Estações do Ano , Temperatura , Tempo (Meteorologia)
2.
Parasit Vectors ; 12(1): 599, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31864403

RESUMO

Anaplasma phagocytophilum is the agent of tick-borne fever, equine, canine and human granulocytic anaplasmosis. The common route of A. phagocytophilum transmission is through a tick bite, the main vector in Europe being Ixodes ricinus. Despite the apparently ubiquitous presence of the pathogen A. phagocytophilum in ticks and various wild and domestic animals from Europe, up to date published clinical cases of human granulocytic anaplasmosis (HGA) remain rare compared to the worldwide status. It is unclear if this reflects the epidemiological dynamics of the human infection in Europe or if the disease is underdiagnosed or underreported. Epidemiologic studies in Europe have suggested an increased occupational risk of infection for forestry workers, hunters, veterinarians, and farmers with a tick-bite history and living in endemic areas. Although the overall genetic diversity of A. phagocytophilum in Europe is higher than in the USA, the strains responsible for the human infections are related on both continents. However, the study of the genetic variability and assessment of the difference of pathogenicity and infectivity between strains to various hosts has been insufficiently explored to date. Most of the European HGA cases presented as a mild infection, common clinical signs being pyrexia, headache, myalgia and arthralgia. The diagnosis of HGA in the USA was recommended to be based on clinical signs and the patient's history and later confirmed using specialized laboratory tests. However, in Europe since the majority of cases are presenting as mild infection, laboratory tests may be performed before the treatment in order to avoid antibiotic overuse. The drug of choice for HGA is doxycycline and because of potential for serious complication the treatment should be instituted on clinical suspicion alone.


Assuntos
Anaplasma phagocytophilum/efeitos dos fármacos , Anaplasmose/tratamento farmacológico , Antibacterianos/administração & dosagem , Anaplasma phagocytophilum/classificação , Anaplasma phagocytophilum/genética , Anaplasma phagocytophilum/isolamento & purificação , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Anaplasmose/transmissão , Animais , Europa (Continente)/epidemiologia , Cavalos , Humanos , Ixodes/parasitologia , Ixodes/fisiologia
3.
Ann Agric Environ Med ; 26(4): 544-547, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31885226

RESUMO

INTRODUCTION: Ticks (Acari: Ixodida) are vectors and/or reservoirs of many pathogens, i.e. Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum and Babesia microti. These pathogens are ethiological agents of such diseases as Lyme borreliosis, human granulocytic anaplasmosis and human babesiosis. OBJECTIVE: The aim of the study was to evaluate the role of the Ixodes ricinus in the transmission of Borrelia burgdorferi sensu lato, Borrelia afzelii, Borrelia garinii, Borrelia burgdorferi sensu stricto, Anaplasma phagocytophilum and Babesia microti in Opolskie Province in Poland. MATERIAL AND METHODS: DNA from 222 ticks was isolated by the ammonia method. The pair of primers specific to the flagelline gene was used to detect of B. burgdorferi s. l. To detect of genospecies of this spirochete, three pairs of internal primers were used. In turn, two pairs of primers specific to the 16S rDNA gene and the 18S rRNA were used, respectively, for the detection of A. phagocytophilum and B. microti. Borrelia burgdorferi s. l., A. phagocytophilum, and B. microti were detected in 4.5%, 2.7% and 5.4% of examined ticks, respectively. RESULTS AND CONCLUSIONS: Of the ten ticks infected with B. burgdorferi s. l., B. afzelii was found in seven, undefinied genospecies in two, and mixed infection with B. afzelii and B. burgdorferi s. s. in one. The study demonstrated the potential risk of exposure of humans and animals to infections of B. burgdorferi s. l., A. phagocytophilum and B. microti in the examined area of Poland.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Vetores Artrópodes/microbiologia , Vetores Artrópodes/parasitologia , Babesia microti/isolamento & purificação , Borrelia burgdorferi/isolamento & purificação , Ixodes/microbiologia , Ixodes/parasitologia , Anaplasma phagocytophilum/genética , Animais , Babesia microti/genética , Babesiose/parasitologia , Babesiose/transmissão , Borrelia burgdorferi/genética , Ehrlichiose/microbiologia , Ehrlichiose/transmissão , Humanos , Ixodes/genética , Ixodes/fisiologia , Doença de Lyme/microbiologia , Doença de Lyme/transmissão , Polônia
4.
Parasit Vectors ; 12(1): 605, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881931

RESUMO

BACKGROUND: Parasites may actively seek for hosts and may use a number of adaptive strategies to promote their reproductive success and host colonization. These strategies will necessarily influence their host specificity and seasonality. Ticks are important ectoparasites of vertebrates, which (in addition to directly affecting their hosts) may transmit a number of pathogens. In Europe, three hard tick species (Ixodidae: Ixodes ariadnae, I. simplex and I. vespertilionis) and at least two soft tick species (Argasidae: Argas transgariepinus and A. vespertilionis) are specialized for bats. METHODS: Here we report data on the host range of these ticks and the seasonality of tick infestation on wild caught bats in south-east Europe. We collected 1803 ticks from 30 species of bats living in underground shelters (caves and mines) from Romania and Bulgaria. On the basis of tick-host associations, we tested several hypotheses on host-parasite evolutionary adaptations regulating host specificity, seasonality and sympatric speciation. RESULTS: We observed significant differences in host specificity and seasonality of abundance between the morphologically different bat specialist ticks (I. simplex and I. vespertilionis) likely caused by their host choice and their respective host-seeking behavior. The two highly generalist, but morphologically similar tick species (I. ariadnae and I. vespertilionis) showed temporal differences in occurrence and activity, thus exploiting significantly different host communities while occurring in geographical sympatry. CONCLUSIONS: We conclude that bat-specialist ticks show a wide range of adaptations to their hosts, with differences in specificity, seasonality of occurrence, the prevalence and intensity of infestation and all these contribute to a successful division of temporal niches of ticks sharing morphologically similar hosts occurring in geographical sympatry.


Assuntos
Argas/fisiologia , Quirópteros/parasitologia , Especificidade de Hospedeiro , Ixodes/fisiologia , Infestações por Carrapato/veterinária , Adaptação Fisiológica , Animais , Argas/classificação , Argas/genética , Bulgária , Quirópteros/classificação , Ixodes/classificação , Ixodes/genética , Filogenia , Romênia , Estações do Ano , Infestações por Carrapato/parasitologia
5.
BMC Infect Dis ; 19(1): 861, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623574

RESUMO

BACKGROUND: Exposure to blacklegged ticks Ixodes scapularis that transmit pathogens is thought to occur peri-domestically. However, the locations where people most frequently encounter infected ticks are not well characterized, leading to mixed messages from public health officials about where risk is highest. METHODS: We conducted a systematic review and meta-analysis on spatial risk factors for tick-borne disease and tick bites in eastern North America. We examined three scales: the residential yard, the neighborhood surrounding (but not including) the yard, and outside the neighborhood. Nineteen eligible studies represented 2741 cases of tick-borne illness and 1447 tick bites. Using random effects models, we derived pooled odds ratio (OR) estimates. RESULTS: The meta-analysis revealed significant disease risk factors at the scale of the yard (OR 2.60 95% CI 1.96 - 3.46), the neighborhood (OR 4.08 95% CI 2.49 - 6.68), and outside the neighborhood (OR 2.03 95% CI 1.59 - 2.59). Although significant risk exists at each scale, neighborhood scale risk factors best explained disease exposure. Analysis of variance revealed risk at the neighborhood scale was 57% greater than risk at the yard scale and 101% greater than risk outside the neighborhood. CONCLUSIONS: This analysis emphasizes the importance of understanding and reducing tick-borne disease risk at the neighborhood scale. Risk-reducing interventions applied at each scale could be effective, but interventions applied at the neighborhood scale are most likely to protect human health. TRIAL REGISTRATION: The study was registered with PROSPERO: CRD42017079169 .


Assuntos
Picadas de Carrapatos/diagnóstico , Doenças Transmitidas por Carrapatos/diagnóstico , Animais , Humanos , Ixodes/fisiologia , Doença de Lyme/diagnóstico , Doença de Lyme/epidemiologia , América do Norte/epidemiologia , Razão de Chances , Características de Residência/estatística & dados numéricos , Fatores de Risco , Picadas de Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia
6.
Pathog Glob Health ; 113(4): 167-172, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31397213

RESUMO

Ixodes ricinus is the most common tick species parasitizing humans in Europe, and the main vector of Borrelia burgdorferi sensu lato, the causative agent of Lyme disease in the continent. This tick species also harbors the endosymbiont Midichloria mitochondrii, and there is strong evidence that this bacterium is inoculated into the vertebrate host during the blood meal. A high proportion of tick bites remains unnoticed due to rarity of immediate symptoms, implying the risk of occult tick-borne infections in turn a potential risk factor for the onset of chronic-degenerative diseases. Since suitable tools to determine the previous exposure to I. ricinus bites are needed, this work investigated whether seropositivity toward a protein of M. mitochondrii (rFliD) could represent a marker for diagnosis of I. ricinus bite. We screened 274 sera collected from patients from several European countries, at different risk of tick bite, using an ELISA protocol. Our results show a clear trend indicating that positivity to rFliD is higher where the tick bite can be regarded as certain/almost certain, and lower where there is an uncertainty on the bite, with the highest positivity in Lyme patients (47.30%) and the lowest (2.00%) in negative controls. According to the obtained results, M. mitochondrii can be regarded as a useful source of antigens, with the potential to be used to assess the exposure to ticks harboring this bacterium. In prospect, additional antigens from M. mitochondrii and tick salivary glands should be investigated and incorporated in a multi-antigen test for tick bite diagnosis.


Assuntos
Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/imunologia , Ixodes/fisiologia , Rickettsiales/imunologia , Picadas de Carrapatos/diagnóstico , Animais , Ensaio de Imunoadsorção Enzimática , Europa (Continente)/epidemiologia , Comportamento Alimentar , Feminino , Humanos , Ixodes/microbiologia , Masculino , Estudos Soroepidemiológicos , Picadas de Carrapatos/epidemiologia
7.
Parasit Vectors ; 12(1): 338, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288866

RESUMO

The taiga tick, Ixodes persulcatus, has previously been limited to eastern Europe and northern Asia, but recently its range has expanded to Finland and northern Sweden. The species is of medical importance, as it, along with a string of other pathogens, may carry the Siberian and Far Eastern subtypes of tick-borne encephalitis virus. These subtypes appear to cause more severe disease, with higher fatality rates than the central European subtype. Until recently, the meadow tick, Dermacentor reticulatus, has been absent from Scandinavia, but has now been detected in Denmark, Norway and Sweden. Dermacentor reticulatus carries, along with other pathogens, Babesia canis and Rickettsia raoultii. Babesia canis causes severe and often fatal canine babesiosis, and R. raoultii may cause disease in humans. We collected 600 tick nymphs from each of 50 randomly selected sites in Denmark, southern Norway and south-eastern Sweden in August-September 2016. We tested pools of 10 nymphs in a Fluidigm real time PCR chip to screen for I. persulcatus and D. reticulatus, as well as tick-borne pathogens. Of all the 30,000 nymphs tested, none were I. persulcatus or D. reticulatus. Our results suggest that I. persulcatus is still limited to the northern parts of Sweden, and have not expanded into southern parts of Scandinavia. According to literature reports and supported by our screening results, D. reticulatus may yet only be an occasional guest in Scandinavia without established populations.


Assuntos
Dermacentor/fisiologia , Ixodes/fisiologia , Distribuição Animal , Animais , Vetores Artrópodes/microbiologia , Vetores Artrópodes/parasitologia , Babesiose/prevenção & controle , Dermacentor/microbiologia , Dermacentor/parasitologia , Cães , Encefalite Transmitida por Carrapatos/prevenção & controle , Monitoramento Epidemiológico , Pradaria , Ixodes/microbiologia , Ixodes/parasitologia , Noruega/epidemiologia , Ninfa/virologia , Países Escandinavos e Nórdicos/epidemiologia , Suécia/epidemiologia , Infestações por Carrapato/epidemiologia , Doenças Transmitidas por Carrapatos/prevenção & controle
8.
Ticks Tick Borne Dis ; 10(5): 1096-1104, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31186200

RESUMO

Ixodes scapularis is responsible for the transmission of a variety of pathogens in North America, including Borrelia burgdorferi sensu stricto, Anaplasma phagocytophilum and Babesia microti. Songbirds have previously been described as agents of tick dispersal, and a combination of empirical data and modeling efforts have implicated songbirds in the range expansion of I. scapularis northward into Canada during spring bird migration. The role of fall bird migration has received comparatively less attention, particularly at a continental scale. The aim of the current research was to use a novel individual-based modeling approach (IBM) to investigate the role of southward migrating songbirds in the dispersal of I. scapularis within the continental United States. The IBM used in this research explicitly models dispersal by two extensively studied migrating songbird species, wood thrush Hylocichla mustelina and ovenbird Seiurus aurocapillus. Our IBM predicts the annual dispersal of more than four million ticks by H. mustelina and S. aurocapillus, notably into areas as far west as the Dakotas, and as far south as Central Alabama. Predicted dispersal locations include areas where the southern phenotype of I. scapularis dominates, suggestive of a possible mechanism for previously described unidirectional gene flow from north to south. In addition, the model demonstrates that three species-specific songbird traits - breeding range, migration timing, and propensity for tick attachment - each play a major role in the relative magnitude of tick dispersal by different songbird species. The pattern of I. scapularis dispersal predicted by this model suggests that migrating songbirds may have contributed to the range expansion of the tick historically, and may continue to do so presently and into the future, particularly as climate changes the geographic areas that are suitable for I. scapularis. Ultimately, widespread tick dispersal by migrating songbirds likely increases the human risk of Lyme disease and other tick-borne diseases in the United States.


Assuntos
Distribuição Animal , Migração Animal , Doenças das Aves/transmissão , Ixodes/fisiologia , Aves Canoras , Infestações por Carrapato/veterinária , Animais , Doenças das Aves/parasitologia , Canadá , Ixodes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Traços de História de Vida , Modelos Biológicos , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Estações do Ano , Infestações por Carrapato/parasitologia , Infestações por Carrapato/transmissão , Estados Unidos
9.
Ticks Tick Borne Dis ; 10(5): 1113-1117, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31201125

RESUMO

Interactions between humans and ticks are often measured indirectly, using surveillance of tick population abundance and pathogen prevalence, or reported human disease data. We used data garnered as part of a free national citizen science research effort to describe actual human exposures to ticks in California. Human-biting ticks (n = 1,905) submitted for identification were predominantly western black-legged ticks (Ixodes pacificus) (68%), American dog ticks (Dermacentor variabilis) (24%), and Pacific Coast ticks (Dermacentor occidentalis) (7%). Tick exposure occurred predominantly during recreational use of the outdoors, rather than exposure near the home environment. Tick submissions peaked in May, but human exposure to ticks occurred throughout the year. Adult I. pacificus were most frequently found on humans during March-May, though previous research demonstrates that questing adults on vegetation are more abundant earlier in the winter.


Assuntos
Dermacentor/fisiologia , Ixodes/fisiologia , Recreação , Animais , California , Dermacentor/crescimento & desenvolvimento , Feminino , Humanos , Ixodes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Estações do Ano
10.
PLoS One ; 14(6): e0217206, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31163042

RESUMO

Estimating the tick-borne encephalitis (TBE) infection risk under substantial uncertainties of the vector abundance, environmental condition and human-tick interaction is important for evidence-informed public health intervention strategies. Estimating this risk is computationally challenging since the data we observe, i.e., the human incidence of TBE, is only the final outcome of the tick-host transmission and tick-human contact processes. The challenge also increases since the complex TBE virus (TBEV) transmission cycle involves the non-systemic route of transmission between co-feeding ticks. Here, we describe the hidden Markov transition process, using a novel TBEV transmission-human case reporting cascade model that couples the susceptible-infected compartmental model describing the TBEV transmission dynamics among ticks, animal hosts and humans, with the stochastic observation process of human TBE reporting given infection. By fitting human incidence data in Hungary to the transmission model, we estimate key parameters relevant to the tick-host interaction and tick-human transmission. We then use the parametrized cascade model to assess the transmission potential of TBEV in the enzootic cycle with respect to the climate change, and to evaluate the contribution of non-systemic transmission. We show that the TBEV transmission potential in the enzootic cycle has been increasing along with the increased temperature though the TBE human incidence has dropped since 1990s, emphasizing the importance of persistent public health interventions. By demonstrating that non-systemic transmission pathway is a significant factor in the transmission of TBEV in Hungary, we conclude that the risk of TBE infection will be highly underestimated if the non-systemic transmission route is neglected in the risk assessment.


Assuntos
Vetores de Doenças , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Ixodes/fisiologia , Ixodes/virologia , Animais , Hungria , Larva/fisiologia , Reprodução , Risco , Estações do Ano , Temperatura
11.
Exp Appl Acarol ; 78(1): 79-91, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31093856

RESUMO

The ornithophilic tick species Ixodes frontalis (Panzer) is spatially distributed in Europe, Asia and northern Africa. It can serve as a carrier of different bacteria and viruses, but little is known of its actual vector competence. In addition, adult females of this species are associated with the avian "tick-related syndrome" (TRS). Like most ornithophilic tick species, I. frontalis is usually collected from bird nests or directly from their hosts. Reports of I. frontalis being collected with the flagging method are scarce. In Germany, the species is considered as very rare. In the few reports that are available, the majority of ticks has been discovered on migrating birds. Therefore, knowledge of the actual distribution of this species in Germany was strictly limited. In this study, we report the finding of 1084 individuals of I. frontalis collected with the flagging method in urban areas and gardens in several regions of Germany. Furthermore, the species was discovered on 35 dead Eurasian blackbirds (Turdus merula) from all over Germany. Finally, we report of five new possible cases of TRS, three in free-ranging birds and two in captive birds, including a Harris's hawk (Parabuteo unicinctus) kept for falconry.


Assuntos
Distribuição Animal , Doenças das Aves/parasitologia , Ixodes/fisiologia , Aves Canoras , Infestações por Carrapato/veterinária , Animais , Feminino , Alemanha , Ixodes/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ninfa/fisiologia , Infestações por Carrapato/parasitologia
12.
Emerg Infect Dis ; 25(6): 1136-1143, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31107213

RESUMO

Most tickborne disease studies in the United States are conducted in low-intensity residential development and forested areas, leaving much unknown about urban infection risks. To understand Lyme disease risk in New York, New York, USA, we conducted tick surveys in 24 parks throughout all 5 boroughs and assessed how park connectivity and landscape composition contribute to Ixodes scapularis tick nymphal densities and Borrelia burgdorferi infection. We used circuit theory models to determine how parks differentially maintain landscape connectivity for white-tailed deer, the reproductive host for I. scapularis ticks. We found forested parks with vegetated buffers and increased connectivity had higher nymph densities, and the degree of park connectivity strongly determined B. burgdorferi nymphal infection prevalence. Our study challenges the perspective that tickborne disease risk is restricted to suburban and natural settings and emphasizes the need to understand how green space design affects vector and host communities in areas of emerging urban tickborne disease.


Assuntos
Distribuição Animal , Borrelia burgdorferi/isolamento & purificação , Ixodes/microbiologia , Doença de Lyme/epidemiologia , Parques Recreativos , Animais , Ecossistema , Humanos , Ixodes/fisiologia , Doença de Lyme/transmissão , Cidade de Nova Iorque/epidemiologia , Ninfa/microbiologia , Ninfa/fisiologia , Fatores de Risco
13.
Ticks Tick Borne Dis ; 10(4): 905-910, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31056485

RESUMO

Research projects in the field of eco-epidemiology of tick-borne diseases often require extensive sampling of arthropod vectors in the field. The aim of our study was to use geographical information systems (GIS) to select appropriate sampling sites of Ixodes ricinus ticks in central European habitat for further ecological studies of vector-borne pathogens (tick-borne encephalitis virus and Borrelia burgdorferi sensu lato). The model area was the Czech-German borderland (the region of South Bohemia and two regions in Germany: the Upper Palatinate and Lower Bavaria) where numerous human tick-borne encephalitis cases are reported annually. We prepared the sampling site design as a multi-criteria evaluation (MCE) task. In the GIS environment, we conducted MCE with a set of environmental, socio-economic and epidemiological data (altitude, vegetation cover, number of tick-borne encephalitis cases recorded in the past, tourist activity). The MCE classified the surveyed area into two classes: suitable for tick collection and unsuitable for tick collection. Subsequently, 50 tick sampling sites were randomly selected in the suitable area: 30 in South Bohemia (Czech Republic) and 20 in the Upper Palatinate and Lower Bavaria regions (Bavaria, Germany). The sampling sites were identified and surveyed in the field. The presence of ticks was confirmed by flagging at each of the selected plots. The described MCE system represents a versatile tool for semi-randomized design of tick sampling sites for research projects in the field of tick-borne pathogen ecology as well as for tick-borne pathogen surveillance programs run by local health authorities.


Assuntos
Ecossistema , Ixodes/fisiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Altitude , Animais , Borrelia burgdorferi/isolamento & purificação , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Feminino , Sistemas de Informação Geográfica , Geografia , Masculino , Amostragem
14.
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
15.
Exp Appl Acarol ; 78(1): 113-126, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31102133

RESUMO

Green areas located within large cities, as natural ecotypes, are a convenient habitat for ticks and their use as recreational areas is associated with the potential risk of acquiring tick-borne diseases. This study estimated the I. ricinus tick density, prevalence of infection with Borrelia species and the diversity of these bacteria in a green urban area (Olsztyn) of north-eastern Poland, an endemic region of tick-borne diseases. The ticks were collected during spring and autumn of 2015, at sites differing in the degree of human pressure and habitat. Borrelia species detection, typing and a molecular phylogenetic analysis were carried out based on the sequenced flaB gene. The overall mean abundance of I. ricinus was 2.0 ± 1.55 ticks per 100 m2. The density of I. ricinus did not vary significantly between sites. According to semi-qualitative tick abundance categories, the collection sites were classified as 'very low' and 'low' tick abundance category. The overall infection rate of I. ricinus with Borrelia spirochaetes was 27.4%. The infection rate of adult ticks (42.0%) was three times higher than with nymphs (14.3%). Based on the restriction patterns and sequencing, B. afzelii (93.1%; 27/29), B. valaisiana 3.5% (1/29) and B. miyamotoi (3.5%; 1/29), related to the relapsing fever (RF) spirochaetes, were detected. No co-infections were found. Borrelia miyamotoi, detected for the first time in ticks in the north-eastern urban areas of Poland, was identical to isolates described as European-type. The Borrelia spirochaete infection rate of I. ricinus ticks in an urban area indicated a high risk of LB. Physicians should also be aware of B. miyamotoi infections among patients with a history of tick-bites in north-eastern Poland.


Assuntos
Vetores Aracnídeos/microbiologia , Vetores Aracnídeos/fisiologia , Borrelia/fisiologia , Ixodes/microbiologia , Ixodes/fisiologia , Animais , Vetores Aracnídeos/crescimento & desenvolvimento , Grupo Borrelia Burgdorferi/fisiologia , Cidades , Feminino , Ixodes/crescimento & desenvolvimento , Masculino , Microbiota , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Polônia , Densidade Demográfica
16.
Ticks Tick Borne Dis ; 10(5): 959-969, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31103456

RESUMO

The most significant processes of arbovirus evolution can be expected to occur in the territories where ticks of different species cohabitate and at the boundaries of virus occurrence, where the probability of the appearance of new virus variants is high due to the possible shift in the main vectors and/or vertebrate hosts. One of the most interesting regions in this regard is the Republic of Tuva. Since most of its territory is covered by mountain ranges and intermountain basins, we were able to study the distribution of vectors and viruses in geographically isolated areas at different altitudes and in various landscapes. From 2008 to 2017, we conducted six expeditions to Tuva and collected 3,077 adult ticks and 24 nymphs. The distribution of tick species was confined to specific landscapes, as follows: Dermacentor nuttalli occurred in steppes, D. silvarum inhabited forest-steppe areas, and Ixodes persulcatus inhabited mixed forests. All three species of ticks were collected on plains and mountain slopes. The range of D. silvarum was shown to be lower than 1300 m above sea level (a.s.l.). Only D. nuttalli and I. persulcatus were collected at higher altitudes. According to our observations, single nymphs of D. nuttalli appear on animals one month before larvae appear. This finding confirms the hypothesis that the immature forms of D. nuttalli are able to overwinter under favourable conditions. We isolated 9 strains and 3 isolates of tick-borne encephalitis virus (TBEV) from I. persulcatus, one strain from D. nuttalli and one strain from D. silvarum. The TBEV strain from D. nuttalli was isolated from the territory inhabited only by Dermacentor ticks. All isolated strains belong to the Siberian subtype of TBEV. TBEV was detected in ticks from all the investigated altitudes. There were no statistically significant differences in the virus prevalence between the Dermacentor and Ixodes ticks. The results of our work provide additional support for the hypothesis of the existence of TBEV foci in areas with an absolute dominance of D. nuttalli.


Assuntos
Distribuição Animal , Vetores Aracnídeos/virologia , Dermacentor/virologia , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/epidemiologia , Ixodes/virologia , Animais , Dermacentor/crescimento & desenvolvimento , Dermacentor/fisiologia , Ecossistema , Encefalite Transmitida por Carrapatos/virologia , Ixodes/crescimento & desenvolvimento , Ixodes/fisiologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Larva/virologia , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Ninfa/virologia , Prevalência , Federação Russa/epidemiologia
17.
Med Mal Infect ; 49(5): 318-334, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31097370

RESUMO

Lyme borreliosis is transmitted en France by the tick Ixodes ricinus, endemic in metropolitan France. In the absence of vaccine licensed for use in humans, primary prevention mostly relies on mechanical protection (clothes covering most parts of the body) that may be completed by chemical protection (repulsives). Secondary prevention relies on early detection of ticks after exposure, and mechanical extraction. There is currently no situation in France when prophylactic antibiotics would be recommended. The incidence of Lyme borreliosis in France, estimated through a network of general practitioners (réseau Sentinelles), and nationwide coding system for hospital stays, has not significantly changed between 2009 and 2017, with a mean incidence estimated at 53 cases/100,000 inhabitants/year, leading to 1.3 hospital admission/100,000 inhabitants/year. Other tick-borne diseases are much more seldom in France: tick-borne encephalitis (around 20 cases/year), spotted-fever rickettsiosis (primarily mediterranean spotted fever, around 10 cases/year), tularemia (50-100 cases/year, of which 20% are transmitted by ticks), human granulocytic anaplasmosis (<10 cases/year), and babesiosis (<5 cases/year). The main circumstances of diagnosis for Lyme borreliosis are cutaneous manifestations (primarily erythema migrans, much more rarely borrelial lymphocytoma and atrophic chronic acrodermatitis), neurological (<15% of cases, mostly meningoradiculitis and cranial nerve palsy, especially facial nerve) and rheumatologic (mostly knee monoarthritis, with recurrences). Cardiac and ophtalmologic manifestations are very rarely encountered.


Assuntos
Doença de Lyme , Doenças Transmitidas por Carrapatos , Animais , Babesiose/diagnóstico , Babesiose/epidemiologia , Babesiose/terapia , Encefalite Transmitida por Carrapatos/diagnóstico , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/terapia , França/epidemiologia , Humanos , Ixodes/fisiologia , Doença de Lyme/diagnóstico , Doença de Lyme/epidemiologia , Doença de Lyme/prevenção & controle , Guias de Prática Clínica como Assunto , Dermatopatias Bacterianas/diagnóstico , Dermatopatias Bacterianas/epidemiologia , Dermatopatias Bacterianas/terapia , Sociedades Científicas/organização & administração , Sociedades Científicas/normas , Doenças Transmitidas por Carrapatos/diagnóstico , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/prevenção & controle
18.
Exp Appl Acarol ; 78(1): 93-112, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31115732

RESUMO

The relict tick Haemaphysalis concinna has a fragmented and focal distribution in Central Europe and Asia. Although in the majority of neighboring countries the occurrence of this tick species is well-documented (i.e., in Germany, Czech Republic, Slovakia, Ukraine), to-date its occurrence in Poland has been registered only once, in 1953 in Troszyn in North-Western Pomerania, close to the German-Polish border. In the present study we report the first documented finding of H. concinna in Western Poland, confirmed both by collection of juvenile ticks from rodent hosts and questing ticks from vegetation. Trapping of rodents took place in the summer of 2018 in three locations in Western Poland (Slonin, Nowy Mlyn 1, Nowy Mlyn 2). Rodents were inspected for ectoparasites, which were detached and fixed in 70% ethanol. All the collected ticks were assigned to species and developmental stages using appropriate morphological keys, and representative individuals were genotyped by molecular methods. A total of 1482 feeding ticks were collected from 106 rodents from three sites. The common tick Ixodes ricinus was found in abundance on small rodents at all three sites; Dermacentor reticulatus ticks were identified at two sites in small numbers and, finally, numerous juvenile H. concinna (n = 427) were found at one of our study sites (Nowy Mlyn 2). The highest prevalence and abundance of H. concinna were recorded on voles, Microtus agrestis and M. oeconomus, from this site in August. Additionally, questing nymphs and adult H. concinna were collected locally from vegetation (n = 20). Genotyping and phylogenetic analysis confirmed the species as H. concinna. A new focus of H. concinna has been described in Western Poland. Our long-term field work monitoring the expansion of the distribution of D. reticulatus in Poland, during which all collected ticks are identified, suggests that H. concinna is still very rare in the country.


Assuntos
Distribuição Animal , Arvicolinae , Ixodidae/fisiologia , Doenças dos Roedores/epidemiologia , Infestações por Carrapato/veterinária , Animais , Dermacentor/crescimento & desenvolvimento , Dermacentor/fisiologia , Feminino , Ixodes/crescimento & desenvolvimento , Ixodes/fisiologia , Ixodidae/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ninfa/fisiologia , Polônia , Doenças dos Roedores/parasitologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia
19.
Ticks Tick Borne Dis ; 10(4): 754-760, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31031164

RESUMO

Ixodes anatis is a species of endophilic (nidicolous) tick species parasitizing brown kiwi (Apteryx mantelli). Even though they are endemic to New Zealand like their host, very little is known about these ticks or their population dynamics and relationships with their hosts. We conducted a study from May 2013 to June 2014 to evaluate the effect of shelter location (one of three gullies), habitat (forest, scrub and pasture) and type (tree, soil and surface) on the abundance of the different life stages of I. anatis. In total, 12,172 ticks were collected from 63 shelters, which were sampled monthly for 11 months over the 14 month period. Un-engorged larvae predominated over other stages accounting for 87.2% of the samples collected. We found that location, habitat in which the shelters were located, and the type of shelter were significant predictors of I. anatis abundance. Tree shelters in forests had significantly higher tick abundance than those in scrub and pasture. Tree and soil shelters in general had significantly more ticks than surface shelters. Shelters located in Kauri Bush a drier site, had higher abundances than those in wetter sites. While some of these changes can be explained with the movement of the host, we believe more research needs to be done on the effect of shelters' microclimate on I. anatis' life cycle.


Assuntos
Ecossistema , Ixodes/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Paleógnatas/parasitologia , Infestações por Carrapato/veterinária , Animais , Feminino , Florestas , Ixodes/fisiologia , Larva , Masculino , Nova Zelândia/epidemiologia , Dinâmica Populacional , Infestações por Carrapato/epidemiologia , Árvores
20.
Parasit Vectors ; 12(1): 144, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30914054

RESUMO

BACKGROUND: Ixodes collaris Hornok, 2016 is a recently discovered tick species associated with bats in Asia. This study provides the description of the male and the larva, as well as high quality drawings of all stages. METHODS: Ticks were collected from cave walls and bats in Phia Oac (Vietnam). DNA was extracted from one individual of each stage/sex, while another was morphometrically analysed. Based on two genetic markers, all ticks were identified as I. collaris. RESULTS: The male of I. collaris has long legs (i.e. the length of Haller's organ exceeds the maximum diameter of tarsus I), unlike the male of I. simplex Neumann, 1906, but similarly to males of I. vespertilionis Koch, 1844 and I. ariadnae Hornok, 2014. The lateral and medial edges of the palpi of male I. collaris are both convexly curved, unlike in I. ariadnae and I. simplex, but similarly to I. vespertilionis. The male of I. collaris has long palpal setae (up to 210 µm), unlike the males of I. ariadnae (30-100 µm) and I. simplex (20-80 µm), but similarly to I. vespertilionis (100-200 µm). Males of I. collaris have sparse distribution of long palpal setae (vs dense in I. vespertilionis) and posteriorly diverging, sclerotized trapezoid ridge dorsally on the basis capituli (posteriorly convergent, U-shaped and less evident in I. vespertilionis). The larva of I. collaris has long legs (unlike the larva of I. simplex, but similarly to I. vespertilionis and I. ariadnae), elongated club-shaped palpi (240 × 70 vs 200 × 90 µm in I. ariadnae, 200 × 70 µm in I. vespertilionis; and 140 × 60 µm in I. simplex:), pentagonal scutum, which is longer than broad (different from I. ariadnae and I. simplex, but similar to that of I. vespertilionis). The larva of I. collaris has strongly concave caudolateral margin of ventral basis with perpendicular angle (vs slightly concave, with obtuse angle in I. vespertilionis) and a prominent, dark sclerotized edge, "collar" (absent in I. vespertilionis). CONCLUSION: Several features allow to distinguish the male and the larva of I. collaris morphologically from those of other bat-associated ixodid tick species.


Assuntos
Ixodes/fisiologia , Larva/anatomia & histologia , Animais , Ásia , Quirópteros/parasitologia , Ixodes/anatomia & histologia , Masculino , Sensilas , Infestações por Carrapato/veterinária , Vietnã
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