RESUMO
@#In tropical regions, numerous tick-borne pathogens (TBPs) play a crucial role as causative agents of infectious diseases in humans and animals. Recently, the population of companion and pet dogs has significantly increased in Vietnam; however, information on the occurrence of TBPs is still limited. The objectives of this investigation were to determine the occurrence rate, risk factors, and phylogenetic characteristics of TBPs in dogs from northern Vietnam. Of 341 blood samples tested by PCR, the total infection of TBPs was 73.9% (252/341). Babesia vogeli (18SrRNA gene – 30.5%) was detected most frequently in studied dogs followed by Rickettsia spp. (OmpA gene – 27%), Anaplasma platys (groEL gene – 22%), Bartonella spp. (16SrRNA – 18.8%), Mycoplasma haemocanis (16SrRNA – 9.4%) and Hepatozoon canis (18SrRNA gene – 1.2%), respectively. All samples were negative for Ehrlichia canis and Anaplasma phagocytophylum. Co-infection was detected in 31.4% of the samples (107/341) of which, A. platys/Bartonella spp. (34/94,10%), Rickettsia spp./B. vogeli (19/94, 5.6%), and M. haemocanis/B. vogeli (19/94, 5.6%) were recorded as the three most frequent two species of co-infection types. Statistical analysis revealed a significant correlation between TBP infection and several host variables regarding age, breed, and living area in the current study. The recent findings reported herein, for the first time in Vietnam, are essential for local veterinarians when considering the appropriate approaches for diagnosing these diseases. Furthermore, this data can be used to establish control measures for future surveillance and prevention strategies against canine TBPs in Vietnam.
RESUMO
ABSTRACT Rocky Mountain Spotted Fever is a rickettsial disease caused by the bacteria Rickettsia rickettsii. In Brazil, the disease is known as Brazilian spotted fever (BSF), being the most significant tick-borne disease in the country. Among the affected patients, only 5% of cases occur in children aged one to nine years. Typical symptoms of the disease are fever, rash, headache and digestive symptoms. Neurological manifestations such as seizures, aphasia and hemiparesis have been described in few patients. This study aimed to describe the case of an infant diagnosed with BSF who presented severe signs of neurological manifestation.
RESUMO
Abstract The Amblyomma genus (Arachnida: Ixodidae) is widely distributed in South America, with 34 species occurring in Brazil. Amblyomma nodosum Neumann 1889 is a species that predominantly feeds on Passeriformes during immature stages (larvae and nymphs) and anteaters (Myrmecophagidae) during adult stages. The aim of the present study is to report, for the first time, an unusual case of parasitism by adults of A. nodosum on a yellow cururu toad (Rhinella icterica) captured in the city of Nossa Senhora da Glória, Sergipe state (Northeastern Brazil) in the Caatinga biome, and also investigate the presence of DNA of Rickettsia in the collected material. DNA was extracted from all specimens collected (N=8) and subjected to PCR assays based on the tick 16S rRNA endogenous gene and gltA gene for Rickettsia sp. All samples (8/8; 100%) were positive for the 16S rRNA endogenous gene and two amplicons (obtained from one male and one female) were purified and sequenced. The BLASTn analysis of the sequences revealed a high degree of similarity (95-100%) with A. nodosum sequences previously deposited on GenBank, while the phylogenetic analysis clustered the sequences obtained in the same clade as A. nodosum sequences from Brazil.
Resumo O gênero Amblyomma (Arachnida: Ixodidae) é amplamente distribuído na América do Sul, com 34 espécies ocorrendo no Brasil. Amblyomma nodosum Neumann 1889 é uma espécie que se alimenta predominantemente de Passeriformes, durante os estágios imaturos (larvas e ninfas), e de tamanduás (Myrmecophagidae) durante os estágios adultos. O objetivo do presente estudo é relatar, pela primeira vez, um caso incomum de parasitismo por adultos de A. nodosum em um Sapo-cururu (Rhinella icterica), capturado na cidade de Nossa Senhora da Glória, estado de Sergipe (Nordeste do Brasil) na Caatinga, e também investigar a presença de DNA de Rickettsia no material coletado. DNA foi extraído de todos os espécimes (N=8) coletados e submetidos a ensaios de cPCR baseados no gene endógeno 16S rRNA de carrapatos e no gene gltA de Rickettsia sp. Todas as amostras (8/8; 100%) foram positivas para o gene endógeno 16S rRNA e dois amplicons (obtidos de um macho e uma fêmea) foram purificados e sequenciados. A análise BLASTn das sequências revelou um alto grau de similaridade (95-100%) com sequências de A. nodosum previamente depositadas no GenBank, enquanto a análise filogenética agrupou as sequências obtidas no mesmo clado das sequências de A. nodosum do Brasil.
RESUMO
Abstract Ticks are parasitic arthropods that cause significant economic losses to livestock production worldwide. Although Rhipicephalus (Boophilus) microplus, the cattle tick, occurs throughout the Brazilian territory, there is no official program to control this tick, which is the vector of tick fever pathogens. We address the situation of R. (B.) microplus resistance to synthetic acaricides in Brazil, including cattle tick management; the status of tick resistance per Brazilian state; the history of resistance occurrence of different acaricides; multiple resistance occurrence; and the main strategies for integrated tick management. Tick control in Brazil is characterized by management errors. Local laboratories affiliated with federal and state research institutions and universities employ the Adult Immersion Test as a primary diagnostic method to assess acaricide resistance to topically applied drugs. Only three states (Acre, Amapá, and Amazonas) have no reports on resistant populations. Misinformation on tick control strategies, misuse of available products for tick control, no adoption of Integrated Parasite Management (IPM) practices, low technical support to producers, and the high-speed emergence of acaricide-resistant tick populations are the main problems. We also propose a list of needs and priorities for cattle tick control regarding communication, research, and policies.
Resumo Carrapatos são artrópodes parasitos que causam perdas econômicas significativas na produção de bovinos em todo o mundo. Embora o carrapato bovino - Rhipicephalus (Boophilus) microplus - esteja distribuído em todo o território brasileiro, não há um programa oficial de controle do parasito. Nesta revisão, foi abordada a situação da resistência de R. (B.) microplus aos carrapaticidas sintéticos no Brasil, incluindo: controle do carrapato; estado da resistência por estado; histórico da ocorrência de resistência a diferentes carrapaticidas; resistência múltipla; e as principais estratégias para o manejo integrado de carrapatos. No Brasil, laboratórios locais empregam empregam, inicialmente, o teste de imersão de adultos como método diagnóstico de resistência aos carrapaticidas. Apenas três estados (Acre, Amapá e Amazonas) não têm relatos de populações resistentes. O controle de carrapatos, no Brasil, é caracterizado por erros de manejo, há desinformação sobre estratégias de controle de carrapatos, uso inadequado dos produtos disponíveis, falta de adoção de práticas de manejo integrado de parasitos (MIP), baixo suporte técnico aos produtores e a rápida emergência de populações de carrapatos multirresistentes a carrapaticidas. Ao final, propõe-se uma lista de necessidades e prioridades para o controle de carrapatos em bovinos com relação à comunicação, pesquisa e políticas públicas.
RESUMO
Resumen Se informa un caso autóctono de rickettsiosis por Rickettsia parkeri, ocurrido en junio del 2018 en la zona selvática del Parque Provincial Urugua-í, Misiones, Argentina, región sin registros previos de esta enfermedad en humanos. Se describen los aspectos epidemiológicos, ecológicos, clínicos y de laboratorio necesarios para el diagnóstico oportuno y el tratamiento adecuado. Se resalta el hecho de considerar a las rickettsiosis como diagnóstico diferencial ante un paciente con síndrome febril agudo exantemático; el antecedente epidemiológico de exposición al vector característico de la región, garrapatas del género Amblyomma, es un elemento fundamental.
Abstract We report an autochthonous case of Rickettsia parkeri rickettsiosis occurred in June 2018 in a forested area of the Urugua-í Provincial Park, Misiones, Argentina. No previous records of this disease in humans have been previously reported in this region. The epidemiological, ecological, clinical, and laboratory features required for a proper diagnosis and adequate treatment are described here. The fact of considering rickettsiosis as a differential diagnosis in a patient with exanthematic acute febrile syndrome is highlighted, being the epidemiological history of exposure to the vector (ticks of the genus Amblyomma) an essential element.
RESUMO
Purpose: The objective was to study the positivity of the Weil–Felix test (WFT) in epidemic retinitis (ER) during the course of the disease. Methods: This is a retrospective, observational case series of patients diagnosed with ER and presented to a tertiary eye care hospital in south India. Patients with positive WFT at the presentation, and who underwent a follow?up WFT during or after the resolution of ER were studied from September 2019 to March 2022. Patient’s demographics, timings of clinical presentation and resolution, and investigation details with a special focus on WFT positivity and its duration were noted. Results: Sixteen patients were studied. Patients presented after 5 weeks of the fever (range: 2?12 weeks, median: 4). After 1?2 months, WFT was still positive in eight patients (50%). Only in one patient titers increased after 1 month, while in others, the titers decreased (n = 11) or remained the same (n = 4). Repeated tests in those patients (n = 6) after 3?4 months turned negative. Resolution of ER was seen at 1.35 months (range: 1?3 months) after the presentation. The mean duration for WFT to turn negative was 2 months from the presentation (range: 1?4 months) or 3.2 months of the fever (range: 1.5?6 months). Conclusion: In contrast to the reported physician’s observation of increasing titers of WFT after rickettsial fever, ophthalmologists may observe decreasing WFT titers in ER. The clinical resolution of ER may precede the normalization of WFT. Follow?up WFT titers should be studied in larger series in confirmed cases of rickettsial?ER to validate the affordable and readily available WFT in India
RESUMO
This study was aimed at identifying species of ticks and investigating infections with tick-borne pathogens a-mong people in Yadong,Tibet.The total of 23 ticks(Ixodes and Haemaphysalis)collected from livestock in Yadong,Tibet in July 2021,the gene sequences of cytochrome oxidase subunitⅠ(COX Ⅰ),mitochondrial 16S ribosomal DNA(16S rDNA)and mitochondrial 12S ribosomal DNA(12S rDNA)were identi-fied on the basis of molecular biology classification.The gene sequences of spotted fever group rickettsia(SFGR),Borrelia burgdorferi,Francisella tularensis and Coxiella burnetii in ticks were amplified by PCR and sequenced,and phylogenetic ana-lyses were performed.In addition,184 serum samples collected from Yadong in 2021 were screened for antibodies to Lyme dis-ease,Q fever,spotted fever,and tularemia by ELISA,and infections with tick-borne pathogens in Yadong were comprehen-sively analyzed.The ticks(Ixodes)collected in Yadong,Tibet,were grouped into two categories.The COX Ⅰ,16S rDNA,and 12S rDNA gene sequences of the ticks had 99.5%,97.57%,and 99.12% similarity,respectively,to those of Ixodes nuttallia-nus in GenBank.The similarities between the COX Ⅰ and 16S rDNA gene sequences of another Ixodes tick species and the COXⅠ and 16S rDNA gene sequences of Ixodes ovatus in GenBank were 88.29% and 95.75%,respectively.The similarity between the COX Ⅰ,16S rDNA,and 12S rDNA gene sequences of Haemaphysalis ticks and those of Haemaphysalis Tibet in GenBank were 96.04%,96.17%,and 97.47%,respectively.The sequence amplification results for Borrelia burgdorferi,Francisella tularensis,and Coxsiella burnetii in 23 ticks were negative,whereas gltA gene amplification of spotted fever group Rickettsia in 23 ticks was positive.The similarity of gltA gene sequences with respect to those of Candidatus Rickettsia tarasevichiae,Rickettsia raoultii,Rickettsia canadensis,and a Rickettsia endosymbiont of Eucalyptus brunneri in GenBank was 96.77%,96.76%,95.35%,and 95.35%,respectively.Among 184 serum samples from Yadong,the positivity rates of Lyme disease,Q fever,spotted fever,and tularemia were 6.52%,12.50%,8.70%,and 10.87%,respectively.These results indicated that the 23 parasitic ticks collected in Yadong,Tibet,in July 2021 were Ixodes nuttallianus,Ixodes ovatus and Haemaphysalis ti-betensis,and 23 ticks were infected with SFGR.Lyme disease,Q fever,spotted fever,and tularemia infection were prevalent in the population of Yadong.Therefore,efforts to control tick-borne diseases must be strengthened.
RESUMO
Ticks are obligate, haematophagous arthropods that are distributed across the world, which may transmit more than 200 pathogens, including viruses, bacteria and parasites. A large number of tick species are widespread in China, and their transmitting tick-borne viral diseases pose a great threat to human health in endemic foci. This review describes the epidemiology of common, emerging and potentially pathogenic tick-borne viruses in China, and recommends the assessment of public health significance and pathogenicity of emerging tick-borne viruses using reverse microbial etiology, so as to provide insights into the management of emerging tick-borne diseases in China.
Assuntos
Animais , Humanos , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/microbiologia , Vírus/genética , Saúde Pública , China/epidemiologiaRESUMO
As the second largest vector of infectious diseases, ticks carry and transmit various pathogens that cause human infections and pose a serious public health hazard. In recent years, there has been an ongoing epidemic of tick-borne fever with thrombocytopenia syndrome virus (SFTSV), as well as the occurrence of human infections by brand-new viruses such as Jingmen tick virus (JMTV) and Alongshan virus (ALSV) in China. This paper will review the advancement of disease clinical characteristics, laboratory methods of virus isolation, immunology and molecular biology of these emerging tick-borne viral diseases in China.
RESUMO
@#Objective To express and purify the E protein Domain Ⅲ(ED Ⅲ) of tick-borne encephalitis virus(TBEV) in tandem and prepare the corresponding polyclonal antibody.Methods The TBEV RNA was extracted by Trizol method,and then reversely transcribed into cDNA,which was used as template to amplify ED Ⅲ gene fragment by PCR.Two ED Ⅲ gene fragments were ligated into fusion gene by the hydrophobic flexible polypeptide(G_4S)_3 using overlapping PCR,which was then linked to prokaryotic expression vector pET-28a(+) to construct the recombinant expression plasmid pET-28a-2ED Ⅲ.After sequencing,pET-28a-2ED Ⅲ was transformed into E.coli BL21(DE3) competent cells,induced by IPTG and purified by Ni~(2+) affinity chromatography.Female New Zealand white rabbits were immunized with the renatured recombinant protein to prepare polyclonal antibody.The antibody titer was detected by indirect ELISA and the specificity was identified by Western blot.The homology of ED Ⅲ amino acid sequence between TBEV and other flaviviruses was analyzed by DNAMAN software.Results The recombinant plasmid pET-28a-2ED Ⅲ was identified by sequencing,and the amplified sequence contained two genes consistent with the E sequence of TBEV "Senzhang" strain(JQ650523.1) included on GenBank,indicating that the recombinant plasmid was constructed correctly.The recombinant 2ED Ⅲ protein was expressed mainly in the form of inclusion bodies,with a relative molecular mass of about 21 000 and a purity of 97.5%.The titer of rabbit anti-2ED Ⅲ serum polyclonal antibody was 1:10~7,which reacted specifically with TBEV whole virus.DNAMAN software alignment showed that the homology of ED Ⅲ amino acid sequences between TBEV and Japanese encephalitis virus(JEV),yellow fever virus(YFV) and Dengue virus(DENY) was 36.56%,9.28% and 30.77%,respectively.Conclusion The TBEV envelope ED Ⅲ tandem recombinant expression plasmid pET-28a-2ED Ⅲ was successfully constructed.The expressed recombinant 2ED Ⅲ protein had good reactivity and immunogenicity,and the prepared polyclonal antibody had high titer.
RESUMO
@#Objective To develop and verify a plaque method for detection of infectious titer of tick-borne encephalitis virus(TBEV)strain(PHKT strain for short)adapted to primary hamster kidney(PHK)cells.Methods PHK cells were infected with TBEV,a primary mouse brain adaption strain,and passed consecutively for 12 passages.The titer of PHKT was detected by plaque method(Monolayer BHK-21 cells were infected with PHKT of various passages at different dilution ratios,and the plaque number was calculated by neutral red staining)and challenge titration in mouse brain(Mice were challenged with PHKT of various passages at different dilution ratios through brain cavity,0.03 mL for each,observed continuously for 14 days,and calculated for the median lethal dose(LD50)by Reed-Muench method)respectively,and the correlation between the results of two methods was analyzed.The developed plaque method for the detection of TBEV titer was verified for specificity,repeatability and intermediate precision.Results The plaque titer of PHKT virus was up to8.9 lgPFU/mL;The correlation between the results of plaque method and mouse brain challenge titration method was good(r = 0.92);The specificity of plaque method for detecting infectious titer of PHKT virus was good,and the coefficients of variation(CVs)of repeatability and intermediate precision were both less than 5%.Conclusion A plaque method for detecting infectious titer of PHKT virus was developed,which may be used as an alternative method for challenge titration in mouse brain.
RESUMO
@#We aimed at determination of acaricidal, larvacidal, and repellent activities of green synthesized silver nanoparticles (SNP) against Hyalomma dromedarii as one of the most common ticks in camels. SNP were green synthesized by reducing Lupinus albus extract through the precipitation technique. The acaricidal, larvicidal, and repellent activity of SNP against H. dromedarii was studied through the adult immersion test (AIT), the larval packet test (LPT), the vertical movement behavior of tick’s larvae method, anti-acetylcholinesterase (AChE) activity, and oxidative enzyme activity. The green synthesized SNP displayed a spherical form with a size ranging from 25–90 nm; whereas the most distribution of particles size was reported at 50-65 nm. SNP dose-dependently (p<0.001) increased the mortality rate of H. dromedarii adult; whereas at 16 and 32 µg/mL completely killed the adult females. Treatment of exposure of H. dromedarii adult to SNP markedly (p<0.001) declined the mean number, weight, and hatchability of eggs. Treatment of H. dromedarii larvae with SNP reduced the viability rate of larvae with the LC50 and LC90 values of 3.1 and 6.9 µg/mL, respectively. Exposure of H. dromedarii larvae to SNP, especially at ½ LC50 and LC50, markedly (p<0.001) increased the oxidative stress and declined the level of antioxidant enzymes in H. dromedarii larvae; whereas, markedly suppressed the AChE activity of the larvae stage of H. dromedarii in comparison to the control group. These results showed that SNP green synthesized by L. albus extract had promising acaricidal, larvicidal and repellent activity against H. dromedarii adults and larvae as a dose-dependent response. SNP also considrably decreased the level of acetylcholinesterase and antioxidant activity and also provokes oxidative stress in H. dromedarii larvae. However, more investigation must be designed to clear the accurate mechanisms and the efficacy of SNP in practical use.
RESUMO
Abstract The tick Amblyomma tigrinum inhabits areas with diverse climatic conditions, with adult stages parasitizing wild canids, such as chilla (Lycalopex griseus) and culpeo (Lycalopex culpaeus) foxes. We described the infestation loads in wild foxes captured at three sites (periurban, rural and wild) through an anthropization gradient in north-central Chile. We tested whether local-scale environmental and/or individual host factors can predict tick abundance by using negative binomial models. During 2018-2020 (spring and summer), we captured 116 foxes (44 chillas and 72 culpeos), and 102 of them were infested with ticks (87.9%, CI=80.6-93.2%). We collected 996 A. tigrinum adult ticks, estimating a total mean abundance of 8.6±0.8 ticks/host. Periurban and rural foxes harbored greater tick loads than foxes from the wild site (2.34 and 1.71 greater, respectively) while tick abundance in summer decreased by up to 57% compared to spring. Tempered, more humid climate conditions of the periurban site could favor the development and survival of adults A. tigrinum; and ticks may have adopted a quiescent stage or similar survival mechanisms to cope with summer temperature increases related to the ongoing megadrought. Further studies are warranted to understand the underlying factors determining the life cycle of A. tigrinum at larger spatiotemporal scales.
Resumo Amblyomma tigrinum habita em áreas com diversas condições climáticas, com estágios adultos, geralmente, parasitando canídeos silvestres, como chilla (Lycalopex griseus) e culpeo (Lycalopex culpaeus). Neste trabalho, são descritas as cargas de infestação de A. tigrinum em raposas silvestres, capturadas em três locais (periurbano, rural e silvestre) no centro-norte do Chile. Foi testado se os fatores ambientais e/ou individuais do hospedeiro, em escala local, podem prever a abundância de carrapatos, usando-se modelos binomiais negativos. Durante 2018-2020 (primavera e verão), foram capturadas 116 raposas (44 chillas e 72 culpeos), e 102 delas estavam infestadas por carrapatos (87,9%, IC=80,6-93,2%). Foram coletados 996 carrapatos adultos de A. tigrinum, estimando-se uma abundância média total de 8,6±0,8 carrapatos/hospedeiro. As raposas periurbanas e rurais abrigaram cargas de carrapatos maiores do que as raposas do local silvestre (2,34 e 1,71 maior, respectivamente), enquanto a abundância de carrapatos, no verão, diminuiu até 57% em comparação com a primavera. As condições climáticas temperadas e mais úmidas do sítio periurbano podem favorecer o desenvolvimento e a sobrevivência dos adultos de A. tigrinum; e os carrapatos podem ter adotado um estágio quiescente ou mecanismos de sobrevivência semelhantes, para lidar com os aumentos de temperatura no verão, relacionados à mega seca em andamento.
RESUMO
Abstract Background: Ehrlichia chaffeensis is responsible for most cases of human ehrlichiosis, an acute febrile tick-borne disease. This clinical entity is more commonly reported in adults from the United States. Therefore, it is of special interest to characterize this disease in children, given that very few cases in children have been reported outside of this country. Case report: We describe the case of a 15-year-old female from northeastern Mexico with a five-day history of myalgias, arthralgias, fever, abdominal pain, rash, and somnolence. The possibility of tick-borne disease was suspected considering that she lived with three tick-infested dogs that had recently died and a neighbor with similar symptoms who deteriorated rapidly and died a week earlier. Ehrlichia spp. was detected in blood samples by polymerase chain reaction. The patient completed a seven-day course of doxycycline and was discharged with complete resolution of symptoms. Conclusions: This case is the first report of ehrlichiosis in a pediatric patient in Mexico, illustrating the importance of considering tick-borne diseases as a differential diagnosis in patients with rash, fever, and altered level of consciousness. This initial clinical presentation may be indistinct from other conditions such as dengue, meningococcemia, and multisystem inflammatory syndrome in children (MIS-C), among others.
Resumen Introducción: Ehrlichia chaffeensis es responsable de la mayoría de los casos de ehrlichiosis humana, una enfermedad febril aguda transmitida por garrapatas. Esta entidad clínica se reporta con mayor frecuencia en adultos de Estados Unidos. Por lo tanto, es de especial interés caracterizarla en niños, dado que se han reportado muy pocos casos en niños fuera de este país. Caso clínico: Se describe el caso de una paciente de sexo femenino de 15 años, originaria y residente del noreste de México con una historia de cinco días de mialgias, artralgias, fiebre, dolor abdominal, erupción cutánea y somnolencia. Se sospechó la posibilidad de una enfermedad transmitida por garrapatas considerando que convivió con tres perros infestados de garrapatas que habían muerto recientemente y una vecina con síntomas similares, quien se deterioró rápidamente y murió una semana antes. Ehrlichia spp. se detectó en una muestra sérica mediante reacción en cadena de la polimerasa. La paciente completó un curso de siete días de doxiciclina y fue dada de alta con resolución de los síntomas. Conclusiones: Este caso es el primer reporte de ehrlichiosis en un paciente pediátrico en México que ilustra la importancia de considerar enfermedades transmitidas por garrapatas dentro del diagnóstico diferencial de pacientes con exantema, fiebre y alteración del estado de conciencia. Esta presentación clínica inicial puede ser indistinguible de otras entidades como dengue, meningococcemia y síndrome multisistémico inflamatorio, entre otras.
RESUMO
Tetradenia riparia (Hochst.) Codd (Lamiaceae) is a shrub, commonly known as ginger bush or false myrrh, and several studies have shown that T. riparia exhibits a variety of biological properties. This study aimed to determine the chemical composition of T. riparia essential oil and its fractions, investigate their anticholinesterase activity, and assess their larvicidal activity against the cattle tick Rhipicephalus microplus and the mosquito Aedes aegypti. Eleven essential oil fractions were obtained by fractionation and analyzed by gas chromatography/mass spectrometry. Larvicidal activity against R. microplus and third-instar A. aegypti was assessed using a larval packet test and a larval immersion test, respectively. Anticholinesterase activity was determined by a bioautographic method. Forty-nine compounds were identified in the essential oil, of which the major classes were oxygenated sesquiterpenes (45.95%) and sesquiterpene hydrocarbons (35.20%) and the major components were isospathulenol (17.40%), ß-caryophyllene (15.61%), 14-hydroxy-9-epi-caryophyllene (10.07%), 14-hydroxy-α-muurolene (8.32%), and 9ß,13ß-epoxy-7-abietene (5.53%). Bioassays showed that T. riparia essential oil (LC50 = 1.56 µg/mL) and FR3 (LC50 = 0.30 µg/mL) were the most active against R. microplus and A. aegypti larvae, respectively. The essential oil and FR1, FR2, and FR3 exhibited acetylcholinesterase inhibitory activity. These results indicate that T. riparia essential oil and its fractions hold promise in the development of novel, environmentally safe agents for the control of R. microplus and A. aegypti larvae.
Assuntos
Carrapatos , Aedes , Lamiaceae/toxicidade , Lamiaceae/química , LarvicidasRESUMO
Ornithodoros mimon is an argasid tick species usually associated with bats and marsupials and occasionally parasitizes humans inside their homes. This paper reports a tick infestation in a residence in the municipality of Campinas, located in the interior of the state of São Paulo (SP). This report increases O. mimon occurrence in SP and corroborates its anthropophilic activity. Further studies are needed to clarify its role as a vector of pathogens. We highlighted the presence of O. mimon in an area with a large human population (Campinas) associated with synanthropic animals.(AU)
Ornithodoros mimon é uma espécie de carrapato argasídeo, geralmente associada a morcegos e marsupiais, sendo ocasionalmente relatada parasitando humanos dentro de seus domicílios. Este trabalho relata a infestação por carrapatos em uma residência no município de Campinas, interior do estado de São Paulo (SP). O presente relato amplia a ocorrência de O. mimon no estado de SP, corroborando sua atividade antropofílica, sendo necessários mais estudos para esclarecer o seu possível papel como vetor de patógenos. Destaca-se a presença de O. mimon numa área de grande contingente humano (Campinas), associado a animais sinantrópicos.(AU)
Assuntos
Humanos , Infestações por Carrapato/parasitologia , Infestações por Carrapato/epidemiologia , Ornithodoros/patogenicidadeRESUMO
ABSTRACT In this study, we report the presence of a female Amblyomma americanum tick attached to a former resident of the East Coast of the United States who moved to Mexico city. The amplification and sequencing of gene fragments of the 16S-rDNA and cytochrome c oxidase subunit 1 corroborated the identification of the species of the tick. Additionally, the presence of DNA of Rickettsia amblyommatis was confirmed. This work is the first report of an exotic tick of the genus Amblyomma in a traveler from the US to Mexico and represents the second record of an imported tick attached to humans in Mexico.
RESUMO
Mediterranean spotted fever (MSF) is a tick-borne acute endemic infectious disease caused by Rickettsia conorii. While MSF may progress asymptomatically, it may lead to clinical pictures like severe hemorrhagic fever. In this article, we are presenting an MSF case with signs of high fever, headache, nausea, weakness and generalized maculopapular rash. The diagnosis of the female patient who had a history of contact with a tick-infested dog was confirmed with her clinical and laboratory data. The clinical and laboratory findings of the patient who was given doxycycline by 200 mg/day for 7 days were improved in a short time. Rickettsia conorii serology by indirect immunofluorescence assay method confirmed the diagnosis of MSF. In cases of severe sepsis accompanied by high fever and generalized maculopapular rash where the source of the infection cannot be determined in the short term, carefully questioning exposure to ticks by considering the existing geographical, seasonal and endemic environmental factors may be life-saving in terms of early diagnosis and treatment of MSF, which may become fatal even in the absence of eschars (tache noire). The symptomatology of hemorrhagic fever associated with Rickettsia conorii may be confused with that of sepsis in clinical practice.
RESUMO
Background: Bacteria of the Anaplasmataceae family and canine hemoparasitic protozoans transmitted by ticks are common in Colombia due to circulation and biological adaptation of vector Rhipicephalus sanguineus sensu lato (s.l.). Objective: To detect the circulation of Ehrlichia canis and Hepatozoon canis in sheltered dogs in three municipalities in southern Aburrá Valley, province of Antioquia, Colombia. Methods: Primers were used to amplify the 16S rRNA associated with the Anaplasmataceae family, dsb for Ehrlichia sp. and 18S rRNA for Hepatozoon sp. Results: Of the 357 samples of venous blood obtained, representing all the sheltered dogs in the study zone, Ehrlichia canis DNA was detected in 2.2% of individuals, showing identity of 100% with previous sequences from the GenBank. Hepatozoon canis showed 8.7% (31/357) prevalence of infection, with 100% identity to genotypes from Japan, Brazil, and Spain. Only one sequence of H. canis exhibited a phylogenic divergence concerning H. canis previously reported in Brazil and the Old World. Conclusions: This study confirms the circulation of E. canis and H. canis in asymptomatic shelter dogs in the south-central zone of the Aburrá Valley, province of Antioquia, Colombia. The present study is the first molecular detection of H. canis in the Province of Antioquia and the third report of canine hepatozoonosis from Colombia, highlighting the importance of considering this agent in veterinary clinic.
Antecedentes: Los agentes patógenos transmitidos por garrapatas, tales como las bacterias de la familia Anaplasmataceae y los protozoos hemoparasitarios caninos, son comunes en Colombia debido a la circulación y la adaptación biológica del vector Rhipicephalus sanguineus sensu lato (s.l.). Objetivo: Detectar la circulación de Ehrlichia canis y Hepatozoon canis en perros protegidos en tres municipios del sur del Valle de Aburrá, departamento de Antioquia, Colombia. Métodos: Se usaron cebadores para amplificar el gen 16S rRNA asociado con la familia Anaplasmataceae y el gen dsb para Ehrlichia sp. y el 18S rRNA para Hepatozoon sp. Resultados: De las 357 muestras de sangre venosa obtenidas, que representan a todos los perros de albergues en la zona de estudio, 2,2% fueron positivas para Ehrlichia canis, con 100% de identidad con secuencias anteriores publicadas en todo el mundo. Hepatozoon canis mostró una prevalencia de infección del 8,7% (31/357), con una identidad del 100% con genotipos de Japón, Brasil y España. Solo una secuencia de H. canis exhibió divergencia filogénica en relación con H. canis previamente reportada en Brasil y el Viejo Mundo. Conclusiones: Este estudio confirma la circulación de E. canis y H. canis en perros asintomáticos de albergues en la zona centro-sur del Valle de Aburrá, departamento de Antioquia, Colombia. El presente estudio es la primera detección molecular en el Departamento de Antioquia y el tercer reporte de hepatozoonosis canina de Colombia destacando la importancia de considerar este agente en la clínica veterinaria.
Antecedentes: Agentes patogênicos transmitidos por carrapatos, como bactérias da família Anaplasmataceae e protozoários hemoparasitários caninos, são comuns na Colômbia devido à circulação e adaptação biológica do vetor Rhipicephalus sanguineus sensu lato (s.l.). Objetivo: Detectar Ehrlichia canis e Hepatozoon canis em cães abrigados em três municípios do sul do vale de Aburrá, departamento de Antioquia, Colômbia. Métodos: Os primers foram utilizados para amplificar o rRNA 16S associado à família Anaplasmataceae, o dsb para Ehrlichia sp. e o rRNA 18S para Hepatozoon sp. Resultados: Das 357 amostras de sangue venoso obtidas, representando todos os cães abrigados na zona de estudo, 2,2% foram positivas para Ehrlichia canis, com 100% de identidade com sequências anteriores publicadas em todo o mundo. Hepatozoon canis mostrou uma prevalência de infecção de 8,7% (31/357), com 100% de identidade com genótipos do Japão, Brasil e Espanha. Apenas uma sequência de H. canis apresentou divergência filogênica em relação a H. canis previamente relatados no Brasil e no Velho Mundo. Conclusões: Este estudo confirma a circulação de E. canis e H. canis em cães de abrigo assintomáticos na zona centro-sul do vale de Aburrá, departamento de Antioquia, Colômbia. O presente estudo é a primeira detecção molecular no Departamento de Antioquia e o terceiro relato de hepatozoonose canina na Colômbia, destacando a importância de considerar este agente na clínica veterinária.
RESUMO
Ticks belong to arthropods and and the second largest vector of pathogens. Ticks can spread a variety of pathogens and cause diseases, threatening human health and livestock production. Although tick-borne diseases can be found almost in all regions in China, they are mainly distributed in Xinjiang, Inner Mongolia, Heilongjiang and other border areas. Tick-borne diseases in Xinjiang are rising year by year with a serious situations recently, and there are specific features in the distribution and characteristics of pathogens. This article reviews the etiology, epidemic status and clinical manifestations of major tick-borne infectious diseases in Xinjiang.