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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): 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
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): 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
5.
Klin Lab Diagn ; 64(11): 686-689, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31747499

RESUMO

Based on experimental studies with 10-fold dilutions of two the strains TBEV of the Far Eastern subtype, different in moleculargenetic characteristic complex data of simultaneously taking into account three indicators of their verification (virus titer, ELISA and PCR-RT) were obtained. The efficiency of detecting a genetic marker in PCR compared with ELISA for a weakly pathogenic strain with defects in the genetic structure was higher by a factor of 10, and for a highly pathogenic strain by a factor of 5,000. At the same time, positive results in both reactions with respect to two strains were detected with a virus titer of not less than 1-1.5 log TCID50, i.e. this level of virus in the sample is defined as epidemically significant. An algorithm for conducting research on the verification of TBEV is proposed: 1) Ticks collected from vegetation can be examined by ELISA or by PCR. All positive results can be summarized and considered viral ticks; 2) All samples with positive results only in PCR or ELISA must be investigated in two reactions in order to obtain confirmation of the possible infectivity of the pathogen; 3) To obtain a fast complex result of infection of the removed ticks from patients or blood after a tick bite, studies should be carried out simultaneously in two reactions simultaneously in ELISA and PCR; 4) Isolation virus should be carried out in biological samples (ticks collected from vegetation, ticks removed from patients, the blood of patients with suspected TBE, mammals) only with the same results in PCR and ELISA. Thus, such an approach to verifying TBEV in a tick or in the blood of patients will improve the reliability of laboratory diagnostics, identifying not only markers of TBEV, but also determining the infectivity of the pathogen, which may be the basis for the appointment of early intensive antiviral therapy.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Encefalite Transmitida por Carrapatos/diagnóstico , Ixodes/virologia , Animais , Vírus da Encefalite Transmitidos por Carrapatos/patogenicidade , Ensaio de Imunoadsorção Enzimática , Humanos , RNA Viral , Reprodutibilidade dos Testes
6.
Zootaxa ; 4658(2): zootaxa.4658.2.7, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31716747

RESUMO

A new species of Ixodes is described from two male specimens that have a distinctive ventrolateral horn-like projection on palpal article 1. This structure is not found in any other Australian species, but is similar to that of I. zaglossi Kohls, 1960 from the long-beaked echidna of Papua New Guinea. I present a revised key to accommodate the five males of Australian Ixodes described or re-described since 1970. I also briefly review the 26 Australian species of Ixodes.


Assuntos
Equidna , Ixodes , Ixodidae , Animais , Austrália , Masculino , Papua Nova Guiné
7.
Parasitol Res ; 118(12): 3205-3216, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31720842

RESUMO

In 2014, a new tick species, Ixodes inopinatus, was described, which is closely related to Ixodes ricinus. So far, I. inopinatus has been found in Tunisia, Morocco, Spain, Portugal, Romania, Austria, and southern Germany. No data is yet available regarding occurrence of I. inopinatus in northern Germany and the potential role of I. inopinatus as a vector for tick-borne pathogens. Therefore, 3845 DNA samples from Ixodes ticks collected for prevalence studies on Borrelia spp., Rickettsia spp., and Anaplasma phagocytophilum during the years 2010-2015 in the northern German cities of Hamburg and Hanover were differentiated into I. ricinus or I. inopinatus by sequencing a part of the 16S rRNA gene. In total, 4% (137/3845) of the sequenced ticks were assigned to the species I. inopinatus and 96% (3708/3845) to I. ricinus. The prevalence of Borrelia spp., Rickettsia spp., and A. phagocytophilum DNA in I. inopinatus was 34% (46/137), 46% (63/137), and 3% (4/137), respectively, whereas the prevalence of these bacteria in I. ricinus was 25% (919/3708), 47% (1729/3708), and 4% (135/3708), respectively. Compared with I. ricinus, significantly more I. inopinatus ticks tested positive for Borrelia. To the best of our knowledge, this is the first report of I. inopinatus in northern Germany. Detection of the DNA of Borrelia spp., Rickettsia spp., and A. phagocytophilum in questing I. inopinatus indicates a potential role of this tick species as a vector of these pathogens, which needs to be confirmed by transmission experiments.


Assuntos
Anaplasma phagocytophilum/genética , Vetores Aracnídeos/microbiologia , Borrelia/genética , Ixodes/microbiologia , Rickettsia/genética , Animais , Vetores Aracnídeos/classificação , Vetores Aracnídeos/genética , Alemanha/epidemiologia , Ixodes/classificação , Ixodes/genética , RNA Ribossômico 16S/genética , Doenças Transmitidas por Carrapatos/epidemiologia
8.
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
9.
Cent Eur J Public Health ; 27(3): 235-238, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31580560

RESUMO

OBJECTIVES: Lyme disease (Lyme borreliosis) is a transmissible infection, common in the temperate climate zones. It is caused by a group of spirochetal bacteria known as Borrelia burgdorferi sensu lato complex. The aim of the present work was to investigate the incidence rate of borreliosis in different regions of Bulgaria and to identify possible risk factors for its occurrence. METHODS: National and regional borreliosis incidence rates for 2009-2018 were obtained from the public database of the National Centre of Public Health and Analyses. Their association with some socio-demographic variables and the geographic location (south or north) of the regions was tested with Spearman's correlation analysis and simple linear regression. RESULTS: The mean annual incidence for the last 10 years (2009-2018) in Bulgaria was 6.9 (range 4.1-11.6) cases per 100,000 inhabitants. We found that the Lyme disease was highly fluctuating at regional level with incidence rates varied from 0.3 to 30.9 per 100,000 inhabitants. Several regions showed significantly higher endemicity for the disease. Socio-demographic factors were not found to be important for Lyme disease frequency while the geographic location in the north part of the country was a significant risk factor for it. CONCLUSIONS: Lyme disease is a serious health risk in Bulgaria especially in its northern part - regions on the north are the most vulnerable to a higher incidence of the disease.


Assuntos
Borrelia burgdorferi , Ixodes , Doença de Lyme , Animais , Bulgária , Estudos Epidemiológicos , Humanos , Incidência , Ixodes/microbiologia , Doença de Lyme/epidemiologia
10.
Parasit Vectors ; 12(1): 434, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492171

RESUMO

BACKGROUND: The density of questing ticks infected with tick-borne pathogens is an important parameter that determines tick-borne disease risk. An important factor determining this density is the availability of different wildlife species as hosts for ticks and their pathogens. Here, we investigated how wildlife communities contribute to tick-borne disease risk. The density of Ixodes ricinus nymphs infected with Borrelia burgdorferi (sensu lato), Borrelia miyamotoi, Neoehrlichia mikurensis and Anaplasma phagocytophilum among 19 forest sites were correlated to the encounter probability of different vertebrate hosts, determined by encounter rates as measured by (camera) trapping and mathematical modeling. RESULT: We found that the density of any tick life stage was proportional to the encounter probability of ungulates. Moreover, the density of nymphs decreased with the encounter probability of hare, rabbit and red fox. The density of nymphs infected with the transovarially-transmitted B. miyamotoi increased with the density of questing nymphs and the encounter probability of bank vole. The density of nymphs infected with all other pathogens increased with the encounter probability of competent hosts: bank vole for Borrelia afzelii and N. mikurensis, ungulates for A. phagocytophilum and blackbird for Borrelia garinii and Borrelia valaisiana. The negative relationship we found was a decrease in the density of nymphs infected with B. garinii and B. valaisiana with the encounter probability of wood mouse. CONCLUSIONS: Only a few animal species drive the densities of infected nymphs in forested areas. There, foxes and leporids have negative effects on tick abundance, and consequently on the density of infected nymphs. The abundance of competent hosts generally drives the abundances of their tick-borne pathogen. A dilution effect was only observed for bird-associated Lyme spirochetes.


Assuntos
Doenças dos Animais/epidemiologia , Biota , Florestas , Ixodes/microbiologia , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos/veterinária , Vertebrados/parasitologia , Anaplasma/isolamento & purificação , Animais , Borrelia/isolamento & purificação , Ehrlichia/isolamento & purificação , Ixodes/crescimento & desenvolvimento , Densidade Demográfica , Medição de Risco , Infestações por Carrapato/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia
11.
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
12.
Ticks Tick Borne Dis ; 10(6): 101265, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31447316

RESUMO

Here, we report the first confirmed autochthonous tick-borne encephalitis case diagnosed in Moscow in 2016 and describe the detection of tick-borne encephalitis virus (TBEV) in ticks and small mammals in a Moscow park. The paper includes data from two patients who were bitten by TBEV-infected ticks in Moscow city; one of these cases led to the development of the meningeal form of TBE. Both TBEV-infected ticks attacked patients in the same area. We collected ticks and trapped small mammals in this area in 2017. All samples were screened for the presence of pathogens causing tick-borne diseases by PCR. The TBEV-positive ticks and small mammals' tissue samples were subjected to virus isolation. The sequencing of the complete polyprotein gene of the positive samples was performed. A total of 227 questing ticks were collected. TBEV was detected in five specimens of Ixodes ricinus. We trapped 44 small mammals, mainly bank voles (Myodes glareolus) and pygmy field mice (Apodemus uralensis). Two samples of brain tissue from bank voles yielded a positive signal in RT-PCR for TBEV. We obtained six virus isolates from the ticks and brain tissue of a bank vole. Complete genome sequencing showed that the obtained isolates belong to the European subtype and have low diversity with sequence identities as high as 99.9%. GPS tracking showed that the maximum distance between the exact locations where the TBEV-positive ticks were collected was 185 m. We assume that the forest park had been free of TBEV and that the virus was recently introduced.


Assuntos
Vetores Aracnídeos/virologia , Arvicolinae , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/veterinária , Ixodes/virologia , Murinae , Doenças dos Roedores/epidemiologia , Adulto , Animais , Vetores Aracnídeos/crescimento & desenvolvimento , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/virologia , Feminino , Humanos , Ixodes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/virologia , Masculino , Moscou/epidemiologia , Ninfa/crescimento & desenvolvimento , Ninfa/virologia , Doenças dos Roedores/virologia , Resultado do Tratamento
13.
Przegl Epidemiol ; 73(2): 269-280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31385684

RESUMO

In Poland, out of the 21 species of ticks described, two species have the greatest epidemiological significance: Ixodes ricinus and Dermacentor reticulatus. Their participation in the transmission of etiologic agents of vector diseases such as Lyme disease, tick-borne encephalitis, human granulocytic anaplasmosis, babesiosis, rickettsiosis and many others is widely known. Due to the often severe and sometimes fatal course of diseases transmitted by ticks, a great deal of emphasis is placed on prophylactic activities, minimizing the possibility of biting and transfering pathogens along with the arachnid saliva. In addition to means of personal protection, including appropriate clothing, protective vaccinations, avoiding tick habitats or body checking after returning from this type of places, one of the most important elements of anti-tick prevention is the use of effective repellents. The key role of using the repellent is to discourage the arthropod from attacking and to prevent it from taking food, as a result of which there is no phenomenon of transmission of pathogens from the hematophage to the host organism. The most commonly used substances with arthropod repellent properties are: N-N-diethylm-toluamide (DEET), 3-(N-acetyl-N-butyl) aminopropionic acid ethyl ester (IR3535), icaridine, permethrin and essential oils. However, it should be remembered that no repellent ever protects 100% all the time after application - its use should be considered as one of many elements of personal protection in the prevention of tick bites.


Assuntos
Mordeduras e Picadas/prevenção & controle , Repelentes de Insetos , Doenças Transmitidas por Carrapatos/prevenção & controle , Animais , Dermacentor , Humanos , Ixodes
14.
Klin Lab Diagn ; 64(7): 424-429, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31408595

RESUMO

Molecular genetic monitoring of natural focal of tick-borne infections in the epidemic season of 2018 revealed infectiousness of ixodid ticks causative agents of tick-borne encephalitis (0.58% of cases), Lyme disease (31% of cases), human monocytic ehrlichiosis (1.6% of cases) and granulocytic anaplasmosis (3.9% of cases) is registered and also co-infections of ticks by these infections (2.9% of cases) is revealed in natural and anthropourgic foci (B. burgdorferi s.l.+A. phagocytophilum, B. burgdorferi s.l.+E. chaffeensis/E. muris and B. burgdorferi s.l.+tick-borne encephalitis virus). The major epidemiological importance of ticks of the species I. persulcatus is found, their share being 87,6%. The majority of patients being bitten by a tick were from the southern and southeast areas of Primorye. Contamination of ticks with Borrelia was revealed not only in I. persulcatus, but also in ticks of the Haemaphysalis and Dermacentor. The infectiousness of ticks of B. burgdorferi s.l. (42,3%), tick-borne encephalitis virus (7,7%) and A. phagocytophilum (15,4%) was highest on Russky Island.


Assuntos
Ixodes/microbiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Ehrlichiose/epidemiologia , Monitoramento Epidemiológico , Humanos , Doença de Lyme/epidemiologia , Biologia Molecular , Federação Russa
15.
Ticks Tick Borne Dis ; 10(6): 101269, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31445875

RESUMO

Tick innate immunity involves humoral and cellular responses. Among the humoral effector molecules in ticks are the defensins which are a family of small peptides with a conserved γ-core motif that is crucial for their antimicrobial activity. Defensin families have been identified in several hard and soft tick species. However, little is known about the presence and antimicrobial activity of defensins from the Australian paralysis tick Ixodes holocyclus. In this study the I. holocyclus transcriptome was searched for the presence of defensins. Unique and non-redundant defensin sequences were identified and designated as holosins 1 - 5. The antimicrobial activity of holosins 2 and 3 and of the predicted γ-cores of holosins 1-4 (HoloTickCores 1-4), was assessed using Gram-negative and Gram-positive bacteria as well as the fungus Fusarium graminearum and the yeast Candida albicans. All holosins had molecular features that are conserved in other tick defensins. Furthermore holosins 2 and 3 were very active against the Gram-positive bacteria Staphylococcus aureus and Listeria grayi. Holosins 2 and 3 were also active against F. graminearum and C. albicans and 5 µM of peptide abrogate the growth of these microorganisms. The activity of the synthetic γ-cores was lower than that of the mature defensins apart from HoloTickCore 2 which had activity comparable to mature holosin 2 against the Gram-negative bacterium Escherichia coli. This study reveals the presence of a multigene defensin family in I. holocyclus with wide antimicrobial activity.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Defensinas/genética , Defensinas/imunologia , Ixodes/genética , Ixodes/imunologia , Sequência de Aminoácidos , Animais , Antibacterianos/química , Antifúngicos/química , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Austrália , Candida albicans/efeitos dos fármacos , Defensinas/química , Fusarium/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Filogenia , Alinhamento de Sequência , Transcriptoma
16.
Emerg Infect Dis ; 25(9): 1738-1741, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31441762

RESUMO

Using long-term data on incidences of Lyme disease and tickborne encephalitis, we showed that the dynamics of both diseases in central Europe are predictable from rodent host densities and climate indices. Our approach offers a simple and effective tool to predict a tickborne disease risk 1 year in advance.


Assuntos
Clima , Ratos/fisiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Animais , Reservatórios de Doenças , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/etiologia , Europa Oriental/epidemiologia , Incidência , Ixodes , Doença de Lyme/epidemiologia , Doença de Lyme/etiologia , Fatores de Risco , Doenças Transmitidas por Carrapatos/etiologia
17.
Ticks Tick Borne Dis ; 10(6): 101254, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31327746

RESUMO

Ixodes persulcatus and Ixodes pavlovskyi ticks, two closely related species of the I. ricinus - I. persulcatus group, are widely distributed in the southern part of Western Siberia. Recently, the existence of natural hybrids of I. persulcatus and I. pavlovskyi ticks has been demonstrated. The aim of this study was to evaluate the abundance of I. persulcatus/pavlovskyi hybrids in several locations with different ratios of parental tick species and to investigate the prevalence and genetic variability of a wide range of infectious agents in these hybrids compared to the parental tick species. Natural hybrids of I. persulcatus and I. pavlovskyi ticks were identified in all examined locations in Altai and Novosibirsk, Western Siberia, Russia. The abundance of hybrids varied from 7% to 40% in different locations and was maximal in a location with similar proportions of I. persulcatus and I. pavlovskyi ticks. For the first time, it was shown that hybrids can be infected with the same agents as their parental tick species: tick-borne encephalitis and Kemerovo viruses, Borrelia afzelii, Borrelia bavariensis, Borrelia garinii, Borrelia miyamotoi, Rickettsia helvetica, Rickettsia raoultii, Rickettsia sibirica, "Candidatus Rickettsia tarasevichiae", Anaplasma phagocytophilum, Ehrlichia muris, "Candidatus Neoehrlichia mikurensis", and Babesia microti. The prevalence of most bacterial agents in hybrids was intermediate compared to their parental tick species. Most genetic variants of the identified agents have been previously found in the parental tick species. Wide distribution of I. persulcatus/pavlovskyi natural hybrids implies that I. persulcatus, I. pavlovskyi and their hybrids coexist in all I. persulcatus - I. pavlovskyi sympatric areas.


Assuntos
Hibridização Genética , Ixodes/microbiologia , Ixodes/parasitologia , Anaplasmataceae/classificação , Anaplasmataceae/isolamento & purificação , Animais , Sequência de Bases , Grupo Borrelia Burgdorferi/classificação , Grupo Borrelia Burgdorferi/isolamento & purificação , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Feminino , Ixodes/genética , Masculino , Orbivirus/classificação , Orbivirus/isolamento & purificação , Filogenia , Rickettsia/classificação , Rickettsia/isolamento & purificação , Alinhamento de Sequência , Sibéria
18.
Ticks Tick Borne Dis ; 10(6): 101255, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31280947

RESUMO

The occurrence of Borrelia garinii in seabird ticks, Ixodes uriae, associated with different species of colonial seabirds has been studied since the early 1990s. Research on the population structure of this bacterium in ticks from seabird colonies in the northeastern Atlantic Ocean has revealed admixture between marine and terrestrial tick populations. We studied B. garinii genetic diversity and population structure in I. uriae collected from seabird colonies in the northwestern Atlantic Ocean, in Newfoundland and Labrador, Canada. We applied a multi-locus sequence typing (MLST) scheme to B. garinii found in ticks from four species of seabirds. The B. garinii strains found in this seabird colony ecosystem were diverse. Some were very similar to strains from Asia and Europe, including some obtained from human clinical samples, while others formed a divergent group specific to this region of the Atlantic Ocean. Our findings highlight the genetic complexity of B. garinii circulating in seabird ticks and their avian hosts but also demonstrate surprisingly close connections between B. garinii in this ecosystem and terrestrial sources in Eurasia. Genetic similarities among B. garinii from seabird ticks and humans indicate the possibility that B. garinii circulating within seabird tick-avian host transmission cycles could directly, or indirectly via connectivity with terrestrial transmission cycles, have consequences for human health.


Assuntos
Grupo Borrelia Burgdorferi/genética , Charadriiformes/parasitologia , Variação Genética , Ixodes/microbiologia , Animais , Tipagem de Sequências Multilocus , Terra Nova e Labrador
19.
Ticks Tick Borne Dis ; 10(6): 101241, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31279737

RESUMO

Fifty nymphal Ixodes ricinus ticks collected in Alsace, France, identified by morphological criteria and using MALDI-TOF MS, were tested by PCR to detect tick-associated bacteria and protozoan parasites. Seventy percent (35/50) of ticks contained at least one microorganism; 26% (9/35) contained two or more species. Several human pathogens were identified including Borrelia burgdorferi s.s. (4%), Borrelia afzelii (2%), Borrelia garinii (2%), Borrelia valaisiana (4%), Borrelia miyamotoi (2%), Rickettsia helvetica (6%) and "Babesia venatorum" (2%). Bartonella spp. (10%) and a Wolbachia spp. (8%) were also detected. The most common co-infections involved Anaplasmataceae with Borrelia spp. (4%), Anaplasmataceae with Bartonella spp. (6%) and Anaplasmataceae with Rickettsia spp. (6%). Co-infection involving three different groups of bacteria was seen between bacteria of the family Anaplasmataceae, Borrelia spp. and Bartonella spp. (2%). Results highlight the panel of infectious agents carried by Ixodes ricinus. Co-infection suggests the possibility of transmission of more than one pathogen to human and animals during tick blood feeding.


Assuntos
Ixodes/microbiologia , Ixodes/parasitologia , Animais , Babesia/classificação , Babesia/isolamento & purificação , Bartonella/classificação , Bartonella/isolamento & purificação , Borrelia/isolamento & purificação , França , Ixodes/crescimento & desenvolvimento , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Ninfa/parasitologia , Filogenia , Reação em Cadeia da Polimerase , Rickettsia/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Wolbachia/isolamento & purificação
20.
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
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