Ticks in medical and parasitological research: Globally emerging risks require appropriate scientific awareness and action.

BACKGROUND: The spread of ticks has also led to the emergence of regional, previously unknown tick-borne diseases (TBDs) that pose an immediate threat to public health systems worldwide. People who spend time or work outdoors are at risk without closer awareness of regional exposures. That is especially true for tourists, who very easily come into contact with ticks and get bitten while hiking and climbing. A regional lack of surveillance, lack of awareness, lack of scientific background, and misdiagnosis makes it hard to assess the actual threat properly. METHODS: Therefore, this bibliometric study aims to assess the global research on ticks and some TBDs. Geographical and temporal patterns are elaborated under epidemiological and socioeconomic aspects. That will provide a factual basis for targeted action at the scientific, societal, and policy levels against the growing threat associated with ticks. RESULTS: The USA and Brazil can be identified as the key players in tick research, followed by Russia and some Central European countries. The socioeconomic analysis points to epidemiologically relevant regions, as also shown by comparison with the TBD analysis. A correlation between countries' gross domestic product and publication performance was found. Lack of scientific resources limits the necessary research and surveillance programs. CONCLUSIONS: Many regions that are popular travel destinations are threatened by new tick species and thus new health risks. Therefore, outdoor activities in many locations may pose an unknown hazard that requires regionally differentiated scientific investigation and better, globally networked research strategies.

Molecular characterization of the recombinant protein RmLTI-BmCG-LTB: Protective immunity against Rhipicephalus (Boophilus) microplus.

The bovine tick Rhipicephalus (Boophilus) microplus is found in several tropical and subtropical regions of the world. This parasite transmits pathogens that cause disease, such as babesiosis (Babesia bovis and B. bigemina) and anaplasmosis (Anaplasma marginale). Tick infestations cause enormous livestock losses, and controlling tick infestations and the transmission of tick-borne diseases remains a challenge for the livestock industry. Because the currently available commercial vaccines offer only partial protection against R. (B.) microplus, there is a need for more efficient vaccines. Several recombinant antigens have been evaluated using different immunization strategies, and they show great promise. This work describes the construction and immunological characterization of a multi-antigen chimera composed of two R. (B.) microplus antigens (RmLTI and BmCG) and one Escherichia coli antigen (B subunit, LTB). The immunogenic regions of each antigen were selected and combined to encode a single polypeptide. The gene was cloned and expressed in E. coli. For all of the experiments, two groups (treated and control) of four Angus heifers (3-6 months old) were used. The inoculation was performed via intramuscular injection with 200 µg of purified recombinant chimeric protein and adjuvated. The chimeric protein was recognized by specific antibodies against each subunit and by sera from cattle inoculated with the chimera. Immunization of RmLTI-BmCG-LTB cattle reduced the number of adult female ticks by 6.29% and vaccination of cattle with the chimeric antigen provided 55.6% efficacy against R. (B.) microplus infestation. The results of this study indicate that the novel chimeric protein is a potential candidate for the future development of a more effective vaccine against R. (B.) microplus.

Ticks and Tick-Borne Pathogens of the Caribbean: Current Understanding and Future Directions for More Comprehensive Surveillance.

Ticks are obligate hematophagous arthropods of significant importance to human and veterinary medicine. They transmit a vast array of pathogens, including bacteria, viruses, protozoa, and helminths. Most epidemiological data on ticks and tick-borne pathogens (TBPs) in the West Indies are limited to common livestock pathogens such as Ehrlichia ruminantium, Babesia spp. (i.e., B. bovis and B. bigemina), and Anaplasma marginale, and less information is available on companion animal pathogens. Of note, human tick-borne diseases (TBDs) remain almost completely uncharacterized in the West Indies. Information on TBP presence in wildlife is also missing. Herein, we provide a comprehensive review of the ticks and TBPs affecting human and animal health in the Caribbean, and introduce the challenges associated with understanding TBD epidemiology and implementing successful TBD management in this region. In particular, we stress the need for innovative and versatile surveillance tools using high-throughput pathogen detection (e.g., high-throughput real-time microfluidic PCR). The use of such tools in large epidemiological surveys will likely improve TBD prevention and control programs in the Caribbean.

Estudio descriptivo de la conducta de profesionales de la salud ante el caso de una picadura por garrapata / Descriptive study of healthcare professionals’ management of tick bites

Introducción En los centros de salud rurales se reciben con cierta frecuencia personas afectadas por picadura por garrapata. Hemos querido comparar el trabajo diario del equipo de atención primaria con la evidencia científica actual. Objetivos Describir los métodos y tratamientos habituales ante una picadura por garrapata en la práctica diaria de los diferentes profesionales que componen la muestra, y compararlos con las recomendaciones generales que aportan mayor evidencia científica. Material y métodos Se trata de un estudio observacional, descriptivo y transversal, realizado mediante la recolección de datos a través de cuestionario auto cumplimentado anónimo. Este instrumento se aplicó a una muestra consecutiva constituida por enfermeros, médicos y pediatras de la Unidad de Gestión Clínica de Medina Sidonia (Cádiz, España). ResultadosUna gran mayoría de enfermeros usa algún tipo de producto para facilitar la extracción del artrópodo (10 de los 11 encuestados, 90,91 por ciento), siendo los más utilizados el cloroetilo y la anestesia local. De ellos, 9 la realizan mediante tracción suave con pinzas (81,82 por ciento). De los médicos y pediatras, 3 de los 12 encuestados (25 por ciento) prescriben tratamiento antibiótico profiláctico en todos los casos. De los restantes, 9 facultativos afirman conocer cuál es el de elección y su posología. En ambos casos es elevado el número de profesionales que indican dar consejos post extracción, 11 en el colectivo médico (91,66 por ciento) y 9 en enfermería (81,82 por ciento).Conclusiones Se concluye que la actuación de los profesionales que han participado en este estudio en muchos aspectos no siguen las recomendaciones actuales para la extracción y tratamiento/seguimiento de pacientes afectados por picadura por garrapata. Por tanto, es necesario aumentar el grado de conocimientos de los mismos para garantizar una asistencia de calidad.

Introduction Rural primary health centers frequently treat patients with tick bites. This study compares everyday clinical practice at our primary healthcare center to practices recommended by current scientific evidence. Purpose To describe the everyday management of tick bites by different healthcare professionals and to compare this management to evidence-based therapy guidelines. Design Cross-sectional, descriptive observational study. Methods Data was collected through an anonymous self-completed questionnaire. The form was filled out by a consecutive sample of nurses, physicians and pediatricians of the clinical management unit of Medina-Sidonia (Cádiz). Results Most nurses in the sample group use some type of product to facilitate the extraction of the tick (10 of the 11 surveyed nurses, 90.9 percent. The most frequently used products were chloroethyl and local anesthetic. In addition, nine nurses use gentle traction with tweezers (81.82 percent) to remove the tick. In the physician sample group, 3 out of 12 respondents (25 percent) prescribe antibiotics in all cases and nine stated that they knew which antibiotic should be used as first choice. In both cases, a high number of healthcare providers confirm giving post-extraction advice to patients: 11 in the medical community (91.66 percent) and nine nurses (81.82 percent). Conclusions We conclude that the performance of the healthcare providers that integrate this study does not closely follow general recommendations for extraction, treatment and follow-up care in patients with tick bites. Therefore, there is a need to improve the level of knowledge to ensure quality care in these instances.

Approaches towards tick and tick-borne diseases control

Ticks are obligate haematophagous ectoparasites of wild and domestic animals as well as humans, considered to be second worldwide to mosquitoes as vectors of human diseases. Tick-borne diseases are responsible worldwide for great economic losses in terms of mortality and morbidity of livestock animals. This review concerns to the different tick and tick-parasites control methods having a major focus on vaccines. Control of tick infestations has been mainly based on the use of acaricides, a control measure with serious drawbacks, as responsible for the contamination of milk and meat products, as a selective factor for acaricide-resistant ticks and as an environmental contaminant. Research on alternatives to the use of acaricides is strongly represented by tick vaccines considered a more cost-effective and environmentally safe strategy. Vaccines based on the Bm86 tick antigen were used in the first commercially available cattle tick vaccines and showed good results in reducing tick numbers, affecting weight and reproductive performance of female ticks which resulted in reduction of cattle tick populations over time and consequently lower reduction of the pathogen agents they carry.

Approaches towards tick and tick-borne diseases control.

Ticks are obligate haematophagous ectoparasites of wild and domestic animals as well as humans, considered to be second worldwide to mosquitoes as vectors of human diseases. Tick-borne diseases are responsible worldwide for great economic losses in terms of mortality and morbidity of livestock animals. This review concerns to the different tick and tick-parasites control methods having a major focus on vaccines. Control of tick infestations has been mainly based on the use of acaricides, a control measure with serious drawbacks, as responsible for the contamination of milk and meat products, as a selective factor for acaricide-resistant ticks and as an environmental contaminant. Research on alternatives to the use of acaricides is strongly represented by tick vaccines considered a more cost-effective and environmentally safe strategy. Vaccines based on the Bm86 tick antigen were used in the fi rst commercially available cattle tick vaccines and showed good results in reducing tick numbers, affecting weight and reproductive performance of female ticks which resulted in reduction of cattle tick populations over time and consequently lower reduction of the pathogen agents they carry.

Ticks and tick-borne diseases: a One Health perspective.

Tick-borne diseases are common occurrences in both the medical and veterinary clinical settings. In addition to the constraints related to their diagnosis and clinical management, the control and prevention of these diseases is often difficult, because it requires the disruption of a complex transmission chain, involving vertebrate hosts and ticks, which interact in a constantly changing environment. We provide a contemporary review of representative tick-borne diseases of humans and discuss aspects linked to their medical relevance worldwide. Finally, we emphasize the importance of a One Health approach to tick-borne diseases, calling physicians and veterinarians to unify their efforts in the management of these diseases, several of which are zoonoses.

Erliquiose transmitida aos cães pelo carrapato marrom (Rhipicephalus sanguineus) / Ehrlichiosis transmitted to dogs by tick brown (Rhipicephalus sanguineus)

Os animais da espécie canina representam aqueles que estão mais ligados ao homem, seja pelo apelo sentimental quando utilizados como animais de companhia, ou quando são empregados para serviço e/ou pesquisa. Entretanto, as doenças transmitidas pelos carrapatos, como a erliquiose, vêm causando grandes prejuízos econômicos e na saúde desses animais. Além destas questões, o protocolo estabelecido, o uso indiscriminado de medicamentos por parte dos proprietários que os utilizam como método preventivo provoca resistência às substâncias, gerando dificuldades no tratamento dessa patologia. Ao discorrer sobre o assunto, objetivou-se abordar o tema como forma de contribuir para um melhor conhecimento da biologia dessa doença, bem como a tomada de decisão na adoção de medidas de controle, prevenção e cura.(AU)

The canine species represent those who are more connected to the man, either by the sentimental appeal when used as pets or when they are em­ployed to service and/or research. However, diseases transmitted by ticks such as ehrlichiosis is causing a great economic loss and to the health of these animals. In addition to these issues, the established protocol, the indiscriminate use of drugs by the owners who use them as a preventive method, causes resistance to these substances, implying in difficulties in the treatment of this pathology. To discuss the subject, the objective of addressing the theme is a way of contributing to a better knowledge of the biology of this disease, as well as the decision on the adoption of control, prevention and cure measures.(AU)

Promovendo saúde no Horto Florestal / Promoting health in the Horto Florestal

Trata-se de um estudo desenvolvido numa Unidade de Conservação de São Paulo o Parque Estadual Alberto Lofgrën - PEAL, situado na zona norte da cidade e conhecido como Horto Florestal. Visou identificar iniciativas sobre as diretrizes de promoção da saúde no parque, e a relevância dos determinantes sociais, ambientais e de saúde frente à Febre Maculosa Brasileira - FMB. A área de visitação pública do parque tornou-se importante área de estudo por possuir características epidemiológicas, consideradas pelo programa de controle desta doença, como área de alerta e, portanto, potencial para transmissão. Buscou-se identificar também as ações pedagógicas oferecidas pelo Núcleo de Educação Ambiental para entender a atuação dos monitores ambientais e foi efetuado um levantamento da infraestrutura e funcionamento do PEAL. Foram elaboradas oficinas pedagógicas com os monitores e outros profissionais que mantinham uma atuação de interface com a população para abordagem de temas norteadores do estudo como: educação em saúde e ambiental, promoção da saúde, Febre Maculosa Brasileira, planejamento de ações educativas e controle de carrapatos. Para garantir um processo pedagógico participativo nas oficinas, foram discutidos temas de interesse do grupo e utilizadas uma diversidade de estratégias para estimular nos participantes sentimentos de co-responsabilidade e pertencimento ao processo. Um espaço de reflexão sobre promoção da saúde, qualidade de vida, o ambiente do parque, estratégias pedagógicas e ações de cuidados com a FMB, foi criado, com o objetivo de integrar ações de educação ambiental e de saúde, que articuladas poderiam amplificar a atuação dos profissionais. A coleta de dados foi feita por meio de análise documental, observação de campo, entrevista com a gestora e encontros pedagógicos com os monitores. A análise dos resultados foi construída a partir da triangulação dos dados obtidos das técnicas de pesquisa citadas...

The Caribbean Amblyomma Program: some ecologic factors affecting its success.

The Caribbean Amblyomma Program has been operational for 8 years. However, owing to funding availability, some islands did not commence eradication activities until late 1997. During the past 2 years, 6 of the 9 islands (St. Kitts, St. Lucia, Anguilla, Montserrat, Barbados, and Dominica) under the program have attained the status of provisional freedom from the tropical bont tick (TBT). There are several administrative and technical reasons why the attainment of the program goals took longer than originally anticipated. This paper examines some of the ecologic factors that necessitated the prolongation of the treatment period and the recrudescence of TBT infestation in some islands. The introduction and subsequent spread of the cattle egret, Bulbucus ibis, in the 1960s and 1970s was most likely closely associated with the dissemination of the TBT in the region. At the national or island level, variations in land use are believed to have had a major impact on the eradication efforts in the different islands. Two islands, Antigua and Nevis, both opted out of sugar production several decades ago for economic reasons. Unfortunately, however, land from former sugar estates was not developed for other agricultural purposes and it became "unimproved free-grazing" areas for livestock. Thus, in both Antigua and Nevis, large numbers of livestock tend to become feral or free-ranging, making compliance with the mandatory treatment schedules impossible. In contrast, St. Lucia has large tracts of land allocated to banana plantations and St. Kitts to sugar plantations. Thus, feral or free-ranging livestock were rarely a problem in these islands. These differences in land use management are compared and discussed in relation to their perceived profound impact on TBT eradication efforts in the region.

Laboratory evaluation of the compatibility and the synergism between the entomopathogenic fungus Beauveria bassiana and deltamethrin to resistant strains of Boophilus microplus.

Beauveria bassiana is one of the most promising agents for use as a bioacaricide to control the cattle tick Boophilus microplus, responsible for economic losses and transmission of infectious diseases. With the aim of optimizing the efficacy of chemical products, as well as the use of entomopathogens, the objective of the present study was to evaluate the compatibility and the synergism between this fungus and the drug deltamethrin on a strain of B. microplus that is resistant to this product.

Epidemiologia e controle da tristeza parasitária bovina na regiäo sudeste do Brasil / Epidemiology and control of bovine babesiosis and anaplasmosis in Southeast Region of Brazil

A babesiose bovina e a anaplasmose (Tristeza Parasitária Bovina) säo enfermidades transmitidas pelo carrapato Boophilus microplus e por moscas hematófagas, respectivamente, ocorrendo em caráter endêmico no Brasil, acarretando elevadas perdas econômicas na pecuária. Nesse país, observa-se uma grande variedade de fatores epidemiológicos influenciando sua ocorrência, tais como: variaçäo climática, práticas de manejo, controle de carrapato e introduçäo de bovinos susceptíveis. Assim, esta revisäo aborda aspectos epidemiológicos do controle da anaplasmose e da babesiose bovina do Brasil, com ênfase na regiäo sudeste. Fatores que influenciam a instabilidade e a estabilidade enzoótica de ambas as espécies também säo discutidos. As medidas de controle empregadas atualmente säo: quimioprofilaxia, o uso de acaricidas para o controle de carrapato vetor B. microplus, a premuniçäo e a vacinaçäo.

Babesiosis (Babesia bovis) stability in unstable environments.

Enzootic stability (herd immunity) in bovine babesiosis occurs when the rate of transmission (inoculation rate) of Babesia spp by the tick vector is sufficient to immunize a majority of susceptible calves before the loss of calfhood resistance. The effect of three tick (Boophilus microplus) control strategies (none, threshold, and strategic) on enzootic stability and the likelihood of babesiosis (Babesia bovis) outbreaks was studied using a spreadsheet age-class computer simulation model. The model was driven by weekly bovine tick counts from Brazil and Uruguay. The Eldorado do Sul, RS, Brazil bovine population (30 degrees 05' South latitude) was found to be in a naturally occurring state of enzootic stability, corresponding to an inoculation rate exceeding 0.005 throughout the year. Threshold dipping strategies should not increase the risk of babesiosis in cattle so managed. Strategic dipping resulted in an extended period of enzootic instability lasting 30 weeks, which requires protection of the herd through immunization. Because of the more prolonged low winter temperature conditions, the Tacuarembó, Uruguay bovine population (31 degrees 40' South latitude) was found to be in a naturally occurring state of enzootic instability, characterized by a 28 week period in which the inoculation rate was below 0.005. Strategic dipping should lead to eradication of the babesial parasite from tick and bovine populations, but would not result in eradication of the tick vector. This could lead to subsequent outbreaks if Babesia carrier animals were to be introduced into the herd. In both populations, strategic tick control could be accompanied by concurrent babesiosis vaccination.

Past and present national tick control programs. Why they succeed or fail.

The historical reasons for the introduction of tick control during the nineteenth century are reviewed. Background and concepts for the choice between long-term tick control and tick eradication are compared. Case studies of large-scale tick control or eradication programs in Africa, Australia, the United States, and the Caribbean are used to highlight successes and failures. The main reasons for lack of sustainability, or failure, of programs are discussed. These include the economic constraints that were faced in several African countries, or technical shortcomings such as were perceived as a major problem in Puerto Rico. The successes are generally associated with enforcement of appropriate legislation and good management, such as occurred in Zimbabwe. These case studies are analyzed to identify features that may assist in the implementation of the ongoing tropical bont tick eradication program in the Caribbean. The paper concludes with some practical suggestions for the future, and the need to reassess the economics of control and the potential additional animal health benefits derived from tick control programs.

Trials to control South American ticks with entomopathogenic fungi.

Ticks are parasites of great importance to man, domestic, and wild animals. In spite of the progress of the science, thus far, ticks are controlled mainly by chemical acaricides and when this technique is used in an indiscriminate way it can lead to ambiental pollution and development of tick resistance to acarcides. The studies developed in the Universidade Federal Rural do Rio de Janeiro demonstrate that some isolates of the fungi Metarhizium anisopliae and Beauveria bassiana are pathogens for ticks and their action effects the mortality of ticks and reduces the populational levels in subsequent generations. In future, research needs to address the search of new pathogens; the association of biological with chemical products seeking an synergistic action; the search of formulations that propitiate increased stability, and careful studies on the safety of biological products for use in animals.

The safety and efficacy of Australian tick-borne disease vaccine strains in cattle in Paraguay.

Glycerol preserved, frozen tick-borne disease vaccine strains developed in Australia were imported into Paraguay to test their safety in pregnant Holando heifers and their efficacy against challenge from inoculated local field strains of Babesia bigemina, B. bovis and Anaplasma marginale in Hereford X Criolla heifers. The two Babesia strains proved to be safe and the B. bovis K strain was very effective in providing immunity to a local field strain of B. bovis. The B. bigemina efficacy trial was inconclusive, possibly due to the avirulent nature of the local field strain used in challenge. The A. centrale strain did not prove to be as safe as would be desirable in safety trials, neither did it provide as good protection as the Babesia strains in the efficacy trial. It was concluded that the Babesia strains provided good protection against field challenge in Paraguay and were safe to use in highly susceptible cattle, however an alternative to A. centrale should be sought to provide protection against local strains of A. marginale.