Amblyomma spp. e a relação com a febre maculosa brasileira / Amblyomma spp. and the relationship with Brazilian spotted fever / Amblyomma spp. y la relación con la fiebre maculosa brasileña

Carrapatos são artrópodes de grande importância para a saúde, principalmente por transmitirem doenças aos seus hospedeiros. Espécies do gênero Amblyomma possuem uma ampla variedade de hospedeiros, incluindo o parasitismo em humanos, podendo ser considerados potenciais transmissores de rickettsias do grupo das bactérias causadoras da Febre Maculosa Brasileira (FBM). O objetivo desse trabalho foi realizar uma revisão de literatura sobre as principais espécies deAmblyomma transmissoras da FMB. Foram realizadas pesquisas nas bases de dados de plataformas como SciELO, LILACS e PubMed, e os descritores utilizados foram: “Amblyomma” e “Febre Maculosa Brasileira”, nos idiomas português e inglês. Foram encontrados 55 trabalhos científicos e 05 teses sobre a temática e os resultados confirmaram que os carrapatos das espécies Amblyomma sculptum, A. aureolatum e A. ovale são os principais vetores da FMB, sendo a capivara, os cavalos e os cães os mais importantes reservatórios da cadeia epidemiológica da doença. As regiões Sudeste e Sul lideram os números de casos e óbitos em humanos. É importante conhecer o ciclo de vida, o ambiente e as condições ambientais favoráveis para a manutenção dessas espécies de carrapatos, a fim de diminuir a ocorrência de zoonoses transmitidas por eles, evitando também a expansão da FMB.(AU)

Ticks are arthropods of great importance to health, mainly because they transmit diseases to their hosts. Species of the genus Amblyomma have a wide variety of hosts, including parasitism in humans, being considered potential transmitters of rickettsiae of the bacteria group that cause Brazilian Spotted Fever (BSF). The objective of this work was to carry out a literature review on the main species of Amblyomma that transmit BSF. Searches were carried in the databases of platforms such as SciELO, LILACS and PubMed, and the descriptors were “Amblyomma” and “Brazilian spotted fever”, in the language Portuguese and English. Were found 55 scientific workand 05 theses on the theme and the results confirmed that ticks of the species Amblyomma sculptum, A. aureolatum and A. ovaleare the main vectors of BSF, capybara, horses and dogs being the most important reservoirs of the disease's epidemiological chain. The Southeastern and Southern regions lead the numbers of cases and deaths in humans. It is important to know the life cycle, the environment and the favorable environmental conditions for the maintenance of these tick species, in order to reduce the occurrence of zoonoses transmitted by them, also avoiding the expansion of BSF.(AU)

Las garrapatas son artrópodos de gran importancia para la salud, principalmente porque transmiten enfermedades a sus huéspedes.Las especies del género Amblyomma tienen una amplia variedad de huéspedes, incluido el parasitismo en humanos, y pueden considerarse transmisores potenciales de rickettsias en el grupo de bacterias que causan la fiebre maculosa brasileña (FBM).El objetivo de este trabajo fue realizar una revisión de la literatura sobre las principales especies de Amblyomma que transmiten FMB. Se realizaron búsquedas en las bases de datos de plataformas como SciELO, LILACS y PubMed, y los descriptores utilizados fueron: "Amblyomma" y "Febre Maculosa Brasileña", en portugués e inglés. Se encontraron 55 trabajo científicos y 05 tesis sobre el tema y los resultados confirmaron que las garrapatas de las especies Amblyomma sculptum, A. aureolatum y A. ovale son los principales vectores de FMB, con capibaras, caballos y perros como los reservorios más importantes la cadena epidemiológica de la enfermedad. Las regiones sureste y sur lideran el número de casos y muertes en humanos. Es importante conocer el ciclo de vida, el medio ambiente y las condiciones ambientales favorables para el mantenimiento de estas especies de garrapatas, a fin de reducir la aparición de zoonosis transmitidas por ellos, evitando también la expansión de FMB.(AU)

Amblyomma spp. e a relação com a febre maculosa brasileira / Amblyomma spp. and the relationship with Brazilian spotted fever / Amblyomma spp. y la relación con la fiebre maculosa brasileña

Carrapatos são artrópodes de grande importância para a saúde, principalmente por transmitirem doenças aos seus hospedeiros. Espécies do gênero Amblyomma possuem uma ampla variedade de hospedeiros, incluindo o parasitismo em humanos, podendo ser considerados potenciais transmissores de rickettsias do grupo das bactérias causadoras da Febre Maculosa Brasileira (FBM). O objetivo desse trabalho foi realizar uma revisão de literatura sobre as principais espécies deAmblyomma transmissoras da FMB. Foram realizadas pesquisas nas bases de dados de plataformas como SciELO, LILACS e PubMed, e os descritores utilizados foram: “Amblyomma” e “Febre Maculosa Brasileira”, nos idiomas português e inglês. Foram encontrados 55 trabalhos científicos e 05 teses sobre a temática e os resultados confirmaram que os carrapatos das espécies Amblyomma sculptum, A. aureolatum e A. ovale são os principais vetores da FMB, sendo a capivara, os cavalos e os cães os mais importantes reservatórios da cadeia epidemiológica da doença. As regiões Sudeste e Sul lideram os números de casos e óbitos em humanos. É importante conhecer o ciclo de vida, o ambiente e as condições ambientais favoráveis para a manutenção dessas espécies de carrapatos, a fim de diminuir a ocorrência de zoonoses transmitidas por eles, evitando também a expansão da FMB.

Ticks are arthropods of great importance to health, mainly because they transmit diseases to their hosts. Species of the genus Amblyomma have a wide variety of hosts, including parasitism in humans, being considered potential transmitters of rickettsiae of the bacteria group that cause Brazilian Spotted Fever (BSF). The objective of this work was to carry out a literature review on the main species of Amblyomma that transmit BSF. Searches were carried in the databases of platforms such as SciELO, LILACS and PubMed, and the descriptors were “Amblyomma” and “Brazilian spotted fever”, in the language Portuguese and English. Were found 55 scientific workand 05 theses on the theme and the results confirmed that ticks of the species Amblyomma sculptum, A. aureolatum and A. ovaleare the main vectors of BSF, capybara, horses and dogs being the most important reservoirs of the disease's epidemiological chain. The Southeastern and Southern regions lead the numbers of cases and deaths in humans. It is important to know the life cycle, the environment and the favorable environmental conditions for the maintenance of these tick species, in order to reduce the occurrence of zoonoses transmitted by them, also avoiding the expansion of BSF.

Las garrapatas son artrópodos de gran importancia para la salud, principalmente porque transmiten enfermedades a sus huéspedes.Las especies del género Amblyomma tienen una amplia variedad de huéspedes, incluido el parasitismo en humanos, y pueden considerarse transmisores potenciales de rickettsias en el grupo de bacterias que causan la fiebre maculosa brasileña (FBM).El objetivo de este trabajo fue realizar una revisión de la literatura sobre las principales especies de Amblyomma que transmiten FMB. Se realizaron búsquedas en las bases de datos de plataformas como SciELO, LILACS y PubMed, y los descriptores utilizados fueron: "Amblyomma" y "Febre Maculosa Brasileña", en portugués e inglés. Se encontraron 55 trabajo científicos y 05 tesis sobre el tema y los resultados confirmaron que las garrapatas de las especies Amblyomma sculptum, A. aureolatum y A. ovale son los principales vectores de FMB, con capibaras, caballos y perros como los reservorios más importantes la cadena epidemiológica de la enfermedad. Las regiones sureste y sur lideran el número de casos y muertes en humanos. Es importante conocer el ciclo de vida, el medio ambiente y las condiciones ambientales favorables para el mantenimiento de estas especies de garrapatas, a fin de reducir la aparición de zoonosis transmitidas por ellos, evitando también la expansión de FMB.

Benefits and Drawbacks of Citizen Science to Complement Traditional Data Gathering Approaches for Medically Important Hard Ticks (Acari: Ixodidae) in the United States.

Tick-borne diseases are increasing in North America. Knowledge of which tick species and associated human pathogens are present locally can inform the public and medical community about the acarological risk for tick bites and tick-borne infections. Citizen science (also called community-based monitoring, volunteer monitoring, or participatory science) is emerging as a potential approach to complement traditional tick record data gathering where all aspects of the work is done by researchers or public health professionals. One key question is how citizen science can best be used to generate high-quality data to fill knowledge gaps that are difficult to address using traditional data gathering approaches. Citizen science is particularly useful to generate information on human-tick encounters and may also contribute to geographical tick records to help define species distributions across large areas. Previous citizen science projects have utilized three distinct tick record data gathering methods including submission of: 1) physical tick specimens for identification by professional entomologists, 2) digital images of ticks for identification by professional entomologists, and 3) data where the tick species and life stage were identified by the citizen scientist. We explore the benefits and drawbacks of citizen science, relative to the traditional scientific approach, to generate data on tick records, with special emphasis on data quality for species identification and tick encounter locations. We recognize the value of citizen science to tick research but caution that the generated information must be interpreted cautiously with data quality limitations firmly in mind to avoid misleading conclusions.

An exploratory analysis of demography and movement patterns of dogs: New insights in the ecology of endemic Rocky Mountain-Spotted Fever in Mexicali, Mexico.

An outbreak of Rocky Mountain spotted fever (RMSF) transmitted by the brown dog tick (Rhipicephalus sanguineus sensu lato) has emerged as a major human and animal health concern in Mexicali, Mexico. Due to high rates of brown dog tick infestation, susceptibility, and association with humans, dogs serve as sentinels and have a key role in the ecology of RMSF. A cross-sectional household questionnaire study was conducted in six rural and urban locations to characterize dog ecology and demography in RMSF high-and low-risk areas of Mexicali. In addition, we tracked movement patterns of 16 dogs using a GPS data logger. Of 253 households, 73% owned dogs, and dog ownership tended to be higher in high-risk areas, with a mean dog:human ratio of 0.43, compared with 0.3 in low-risk areas. Dogs in high-risk areas had higher fecundity and roamed more, but the dog density and numbers of free-roaming dogs were comparable. There was a higher proportion of younger dogs and lower proportion of older dogs in high-risk areas. The high proportion of immunologically naïve puppies in high risk areas could result in a lack of herd immunity leading to a more vulnerable dog and human population. The marked increase of space use of free-roaming dogs in high-risk areas suggests that unrestrained dogs could play an important role in spreading ticks and pathogens. As means to limit RMSF risk, practical changes could include increased efforts for spay-neuter and policies encouraging dog restraint to limit canine roaming and spread of ticks across communities; due to dog density is less impactful such policies may be more useful than restrictions on the number of owned dogs.

Probability of Rhipicephalus microplus introduction into farms by cattle movement using a Bayesian Belief Network.

Attempts to eliminate Rhipicephalus microplus from Uruguay have been unsuccessful, and, currently, the country is divided into two areas: a tick-free area and a tick-infested area. In the tick-infested area, different farms face different situations. Some farms are in regions where, due to environmental conditions or a lack of infrastructure, it is difficult to eliminate R. microplus, and the only option is to control it. In contrast, other farms can attempt complete removal. Before deciding whether a farmer should attempt to eliminate R. microplus, the probability of reintroduction must be evaluated. The objective of this study was to develop a probabilistic model based on a Bayesian Belief Network (BBN) to assess the likelihood of a farm becoming infested with R. microplus via the introduction of tick-infested cattle. Only the tick-infested area was considered in the development of this model. Nine variables related to environmental conditions and biosecurity measures, with a focus on cattle movement, were considered. Three different sources of data were used to populate the BBN model: data from the literature; a representative national survey from 2016; and a survey developed to identify biosecurity practices on farms. Model sensitivity and specificity were assessed, and an overall accuracy of 92% was obtained. The model was applied to 33 farms located in the tick-infested area. For one farm, the probability of introduction of R. microplus was 1%; for three farms, the probability was between 21% and 34%; for seven farms, it was between 66% and 76%; and for 22 farms, the probability was greater than 83%. This model was useful for estimating the probability of the introduction of R. microplus into farms, making it possible to assess the impact that the evaluated biosecurity measures have on the probability of introduction and, thus, guiding more objective decision making about the control or elimination of R. microplus from farms.

A high gene flow in populations of Amblyomma ovale ticks found in distinct fragments of Brazilian Atlantic rainforest.

The genetic structure of populations of the tick Amblyomma ovale from five distinct areas of the Brazilian Atlantic rainforest was evaluated via DNA sequencing and associated with the presence of domestic dogs acting as hosts at the edge of forest fragments. Ticks were collected from domestic dogs and from the environment between 2015 and 2017. Four collection areas were located in the surroundings and within the Serra do Mar State Park, São Paulo State (23°37'21"S, 45°24'43"W), where dogs were bimonthly monitored along 2 years using camera traps and GSM trackers. To determine the spatial limits of genetic structure, ticks collected upon dogs living near the Serra do Baturié, Ceará State (4°15'40"S, 38°55'54"W) were included as well. A total of 39 haplotypes of 16S rRNA and Cox 1 mitochondrial genes sequences were observed, with 27 of them coming from areas within the Serra do Mar State Park. No haplotype was shared between the Serra do Mar and the Serra do Baturié indicating isolation of tick populations at the scale of 2000 km. Although three different haplotype lineages of A. ovale occurred within the Serra do Mar State Park, no genetic structure was found across the study sites within this park, suggesting high tick gene flow across a range of 45 km. Monitoring data from domestic dogs and wild carnivores showed that these species share the same habitats at the forest edge, with dogs playing a likely limited role in tick dispersal. Our findings have important implications for understanding the genetic structure of wide spread A. ovale along Brazilian rainforest remnants, which can further be associated to tick-borne infectious agents, such as Rickettsia parkeri, and used for predicting future patterns of tick diversity in the Brazilian Atlantic rainforest.

Experimental evaluation of birds as disseminators of the cosmopolitan tick Rhipicephalus sanguineus (Acari: Ixodidae).

Rhipicephalus sanguineus is believed to be the most widespread tick species of the world and its dissemination seems to rely on the diffusion of its main host, the dog. Empirical observations indicate that several bird species in urban areas regularly steal dog food. Such circumstances create a chance for R. sanguineus ticks to climb on birds and carry ticks to another site. In this work we evaluated experimentally the likelihood of birds (chicks) to either feed and/or carry R. sanguineus ticks from an infested site to another and to infest a host (rabbit) in the new location. Chicks were not suitable hosts for R. sanguineus ticks. Not a single adult tick engorged on chicks, yield as well as weight of engorged larvae and nymphs were very low and feeding period of these ticks was very long. However, a few larvae and, chiefly, nymphs were delivered to a new location either mechanically or after attachment and engorging total or partially on chicks. A few of these ticks fed successfully on rabbits. Further evidence on the capacity of birds to introduce R. sanguineus into non-infested dog settings should be provided by systematic examination of birds from urban areas, close to tick infested households.

Rhipicephalus sanguineus (Acari: Ixodidae), the brown dog tick, parasitizing humans in Brazil.

The objective of this paper is to describe four cases of human parasitism by Rhipicephalus sanguineus (Latrielle) in Brazil. During an investigation regarding the species of ectoparasites of domestic dogs from the metropolitan region of Recife, Pernambuco state, four dog owners were found to be parasitized by ticks. The ticks were collected from these individuals and their dogs. All the ticks were identified as Rhipicephalus sanguineus . These are, to our knowledge, the first four cases of human parasitism by this tick species in Brazil. The possible implications of this finding are discussed here.

Rhipicephalus sanguineus (Acari: Ixodidae), the brown dog tick, parasitizing humans in Brazil

O objetivo deste artigo é descrever quatro casos de parasitismo humano por Rhipicephalus sanguineus (Latrielle) no Brasil. Durante uma investigacão sobre as espécies de ectoparasitas de cães domésticos provenientes da Região Metropolitana de Recife, Pernambuco, quatro proprietários de cães foram encontrados parasitados por carrapatos. Foram coletados carrapatos dos indivíduos e de seus cães. Todos os carrapatos foram identificados como Rhipicephalus sanguineus, sendo, portanto, descritos os primeiros quatro casos de parasitismo humano por esta espécie de carrapato, no Brasil. Neste trabalho, são discutidas as possíveis implicacões epidemiológicas deste achado.

Reptile trade and the risk of exotic tick introductions into southern South American countries.

Ticks exotic for the Neotropical region were found on Python regius imported into Argentina and Chile. All ticks (7 males and 3 females) were classified as Amblyomma latum Koch, 1844 ( = Aponomma latum). Additionally, four lots comprising 18 males of the Argentinean tortoise tick, Amblyomma argentinae Neumann, 1904, were found on a terrestrial tortoise, Chelonoidis chilensis, and on three terrestrial tortoises (probably C. chilensis) imported to Uruguay presumably from Argentina). These findings alert us to the risk of expanding the distribution of reptile parasites and their diseases into regions previously free of these parasites.

Censo de ornithodoros amblus chamberlin (acarina: argasidae) en la isla Mazorca, Lima, Perú / Census of ornithodoros amblus chamberlin (acarina: argasidae) in Mazorca island, Lima, Perú

El objetivo de la presente investigación fue censar a la garrapata Ornithodoros amblus en la Isla Mazorca, Lima, Perú y su relación con la presencia de aves marinas, intensidad de sustrato y viento. El muestreo de las garrapatas se realizó los días 28 y 29 de febrero del año 1998. En cada punto de muestreo se colocó por espacio de tres minutos una tela de tocuyo negra de 0,35 m2. O. amblus presentó una distribución espacial amontonada. La abundancia de garrapatas no estuvo relacionada con la presencia de colonias de aves. Sólo las larvas de O. amblus estuvieron relacionadas con las colonias de aves. La preferencia de los diferentes estados de desarrollo de O. amblus siguió la siguiente secuencia: Guanay > Pelícano > Camanay. Los diferentes estados de desarrollo no se encontraron en relación con las intensidades de guano. Se observó preferencia de las poblaciones de O. amblus con relación a fuertes intensidades de viento. Se discute el efecto del Niño 1997-1998 sobre esta especie de garrapata.

Propagation of the tick Amblyomma variegatum in the Caribbean.

The tropical bont tick, Amblyomma variegatum, is an African tick species which infests livestock and wildlife. It was probably introduced in the central eastern islands of the Caribbean during the 18th or 19th century, with cattle shipped from Senegal. In Africa and the Caribbean, this tick is a vector of heartwater (a rickettsial disease of ruminants) and is associated with acute dermatophilosis (a bacterial skin disease of animals). Until 1948, only Guadeloupe and the neighbouring islands of Marie Galante and Antigua were infested with this tick species. Following increased agricultural commerce between Guadeloupe and Martinique, the latter became infested in 1948. Between 1967 (when the tick was identified in St Croix) and 1988 (when a male tick was reported in St Vincent), fourteen new islands were reached by this tick. Most of the dissemination of the tick to new islands cannot be explained by legal or illegal movements of livestock. Recently-determined circumstantial evidence strongly links the increase in populations of the cattle egret (Bubulcus ibis), a migrating bird established in the Caribbean circa 1960, with increased colonisation of new islands by A. variegatum. Considering the wide range of areas currently occupied by this bird species in the Greater Antilles and on the American mainland, there is a high probability that the tick will also expand its range and invade new areas. Eradication of A. variegatum from the Caribbean and thus from the western hemisphere, and the strengthening of measures to prevent inter-island movements of livestock, would be the only effective means of preventing this threat.