Febre maculosa brasileira na cidade de Jacareí, Vale do Paraíba, SP: descrição dos componentes da paisagem / Brazilian Spotted Fever in the city of Jacareí, Vale do Paraíba region, São Paulo State: description of landscape components

A Febre Maculosa Brasileira (FMB) é uma zoonose infecciosa, febril, aguda e exantemática, de notificação compulsória no Brasil, que tem como agente patogênico bactérias da espécie Rickettsia rickettsii, que são transmitidas por alguns carrapatos do gênero Amblyomma. No Brasil, a maior incidência de casos ocorre no Estado de São Paulo, onde há casos em locais de grande urbanização, e apresenta alta taxa de letalidade que pode variar de 30% à 60% dependendo da região do Estado. A cidade de Jacareí está na região do Vale do Paraíba, onde alguns municípios identificaram em seus territórios casos humanos da doença. No período de 2014 a 2020 ocorreram quatro casos confirmados de FMB com Local Provável de Infecção (LPI) no município de Jacareí, SP, com taxa de letalidade de 100 %. O estudo tem como objetivo descrever a ocorrência de Febre Maculosa Brasileira no Município de Jacareí nesse período. Para essa finalidade, foram selecionadas cinco áreas para esse estudo epidemiológico com propósito descritivo, retrospectivo, e com abordagem ecológica. O estudo foi baseado na revisão dos relatórios de investigações epidemiológicas do banco de dados da Diretoria de Vigilância em Saúde do Município de Jacareí. Os casos humanos descritos tem predomínio de indivíduos do sexo masculino na faixa etária de 50 a 69 anos associados a atividades recreativas e ocupacionais praticadas em áreas urbanas ou periurbanas de mata ciliar ou próximo a estas. As caracteristicas do perfil paisagístico comuns para as áreas estudadas foram determinados por: cobertura vegetal nativa e espelho d'água com alta fragmentação, locais de ocupação e deslocamento humano presentes em 30,4% da área considerada em média, presença de hospedeiros primários, presença de animais sentinela sororreagentes e relato de parasitismo humano. As notificações de parasitismo humano devem ser implementadas no município para uma posterior pesquisa em campo e mapeamento de novos locais possivelmente infestados, e a sinalização com placas informativas das áreas infestadas deve ser mantida e constantemente atualizada. A realização de atividades educativas deve estar voltada para perfil epidemiológico dos indivíduos considerados vulneráveis, e aos profissionais de saúde informando sobre ambientes predispostos para ocorrência da FMB.

Brazilian Spotted Fever (BSF) is an infectious, febrile, acute and exanthematic zoonosis, of compulsory notification in Brazil, which has Rickettsia rickettsii bacterium as its pathogenic agent, which are transmitted by some ticks species of the genus Amblyomma. In Brazil the highest incidence of cases occurs in the State of São Paulo where there are cases in places of great urbanization, and it has a high lethality rate that can vary from 30 % to 60 % depending on the region of the State. The city of Jacareí is located in the Vale do Paraiba region, São Paulo, Brazil. In this region some municipalities have identified human cases of the disease within their territories. In the period between 2014 and 2020 there were four human cases of the disease that had its Probably Local of Infection in the municipality of Jacareí, with a lethality rate of 100%. We aim to describe the occurrence of BSF in the Jacareí municipality in that timeframe. For this goal, five areas were selected for this epidemiological study, with a descriptive, retrospective purpose, and with an ecological approach. The study was based on a review of epidemiological investigation reports from the Jacareí Health Surveillance Directorate database. The described human cases predominantly affect males in the age range of 50 to 69 years, associated with recreational and occupational activities carried out in urban or peri-urban areas near riparian forests. The common landscape characteristics found in the studied areas were determined as follows: native vegetation cover and water mirrors with high fragmentation, human occupation and mobility present in 30.4% of the considered area on average, presence of primary hosts, presence of seropositive sentinel animals, and reports of human parasitism. Notifications of human parasitism should be implemented in the municipality for subsequent field research and mapping of potentially infested areas. Signage with informative plaques in infested areas should be maintained and regularly updated. Educational activities should focus on the epidemiological profile of vulnerable individuals and inform healthcare professionals about environments predisposed to Brazilian Spotted Fever occurence.

Human parasitism by the exotic tick Dermacentor variabilis (Parasitiformes: Ixodida) in Brazil: report of an imported case / Parasitismo humano pelo carrapato exótico Dermacentor variabilis (Parasitiformes: Ixodida) no Brasil: relato de um caso importado

Abstract In June 2012, a tick was found parasitizing a man in the city of São Paulo, who had recently returned from a visit to Pennsylvania, in the northeast of the United States. The tick was removed and sent to the São Paulo State Department of Health, where it was identified as a male of the species Dermacentor variabilis (Say, 1821), according to the literature and taxonomic keys. The tick was subjected to a PCR test to search for rickettsiae, but the result was negative. The fact that a human entered Brazilian territory unaware that he was parasitized by a hard tick not belonging to the national tick fauna is significant because of the possibility that an exotic species could be introduced and take hold in this country. Another major risk to public health is that this arthropod could be infected with the bacterium Rickettsia rickettsii, as this ectoparasite is the main vector of Spotted Fever on the East Coast of North America.

Resumo Em junho de 2012, foi enviado ao serviço da Secretaria de Estado da Saúde de São Paulo um carrapato que foi encontrado em parasitismo sobre um homem adulto na cidade de São Paulo, que havia chegado recentemente de uma viagem de turismo aos Estados Unidos, onde visitou o estado da Pensilvânia, situado na região Nordeste Americana. O carrapato foi identificado como um macho da espécie Dermacentor variabilis, (Say, 1821), de acordo com a literatura e chaves taxonômicas, sendo submetido ao teste da PCR para pesquisa de riquétsias, porém o resultado foi negativo. O fato de um ser humano ter cruzado a fronteira do Brasil, parasitado, sem o seu prévio conhecimento, por um carrapato duro, não pertencente à ixodofauna nacional, é de grande importância pela chance de introdução e estabelecimento no território brasileiro de uma espécie exótica. Outro grande risco para a saúde pública é que esse artrópode poderia estar infectado com a bactéria Rickettsia rickettsii, pois esse ectoparasito é o principal vetor da Febre Maculosa na costa Leste Norte Americana.

Frecuencia de anticuerpos y seroconversión frente a Rickettsia spp. en pacientes atendidos en instituciones de salud del departamento de Caldas, Colombia, 2016-2019 / Frequency of antibodies and seroconversion against Rickettsia spp in patients consulting health institutions in the department of Caldas, Colombia, 2016-2019

Resumen | Introducción. Las rickettsiosis son enfermedades zoonóticas transmitidas por artrópodos que cumplen el papel de vectores y reservorios, y cuyos síntomas son inespecíficos, por lo que su diagnóstico clínico es difícil. La inmunofluorescencia indirecta (IFI) es el método de referencia para el diagnóstico. En Colombia, ha resurgido el interés por su estudio por los casos de rickettsiosis detectados en el norte del departamento de Caldas a partir del 2001. Objetivo. Establecer la frecuencia de anticuerpos y la seroconversión contra Rickettsia spp. en pacientes atendidos en instituciones de salud del departamento de Caldas, Colombia, entre 2016 y 2019. Materiales y métodos. Se hizo un estudio de diseño cuantitativo, observacional y descriptivo, con una muestra no probabilística de 175 pacientes atendidos en diferentes municipios de Caldas, a quienes se les realizó IFI para la detección de anticuerpos en fase aguda y convaleciente contra Rickettsia rickettsii, R. typhi y R. felis. Resultados. El promedio de edad de los pacientes fue de 31 años. Los municipios con mayor proporción de seropositivos fueron Belalcázar, Chinchiná, Filadelfia, La Dorada, La Merced y Manizales. El 66 % tenía mascotas y el 12 % reportó picaduras por artrópodos. Los signos y síntomas más frecuentes fueron cefalea (69,7 %), artromialgia (60 %), y fiebre (58,2 %). La seroprevalencia por IgG fue de 60 % para R. rickettsii, 47,9 % para R. typhi y 24 % para R. felis. Ocho pacientes presentaron seroconversión. Conclusión. Se encontró evidencia de la circulación de rickettsias del grupo de las fiebres manchadas y del grupo del tifus asociada con casos humanos en el departamento de Caldas.

Abstract | Introduction: Rickettsioses are zoonotic diseases transmitted by arthropods acting as vectors and reservoirs. Disease symptoms are nonspecific and, therefore, their clinical diagnosis is difficult. Indirect immunofluorescence (IFA) is the gold standard assay for diagnosis. The interest for conducting studies on these pathologies has resurfaced in Colombia since 2001; besides, previous studies have evidenced cases of rickettsiosis in the north of the department of Caldas. Objective: To establish the frequency of antibodies and seroconversion against Rickettsia spp. In patients consulting health institutions in Caldas, Colombia, from 2016 to 2019. Materials and methods: We conducted a quantitative, observational, and descriptive study on a non-probabilistic sample of 175 patients with symptoms compatible with rickettsiosis who consulted in different municipalities of Caldas, Colombia; IFA was performed to detect antibodies in the acute and convalescent phases against Rickettsia rickettsii, Rickettsia typhi, and Rickettsia felis. Results: The average age of the patients was 31 years. The municipalities with the highest proportion of seropositive cases were Belalcázar, Chinchiná, Filadelfia, La Dorada, La Merced, and Manizales; 66% of patients owned pets and 12% reported arthropod bites. The most frequent signs and symptoms were headache (69.7%), arthromyalgia (60%), and fever (58.2%). IgG seroprevalence was 60% for R. rickettsii, 47.9% for R. typhi, and, and 24% for R. felis. Eight patients presented seroconversion. Conclusion: We found evidence of the circulation of Rickettsia species from the spotted fever group and the typhus group associated with human cases in Caldas.

Nitric Oxide Inhibition of Rickettsia rickettsii.

Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever, is an enzootic, obligate, intracellular bacterial pathogen. Nitric oxide (NO) synthesized by the inducible NO synthase (iNOS) is a potent antimicrobial component of innate immunity and has been implicated in the control of virulent Rickettsia spp. in diverse cell types. In this study, we examined the antibacterial role of NO on R. rickettsii. Our results indicate that NO challenge dramatically reduces R. rickettsii adhesion through the disruption of bacterial energetics. Additionally, NO-treated R. rickettsii cells were unable to synthesize protein or replicate in permissive cells. Activated, NO-producing macrophages restricted R. rickettsii infections, but inhibition of iNOS ablated the inhibition of bacterial growth. These data indicate that NO is a potent antirickettsial effector of innate immunity that targets energy generation in these pathogenic bacteria to prevent growth and subversion of infected host cells.

Serological evidence of Rickettsia in horses from a semi-arid Brazilian region / Evidência sorológica de Rickettsia em cavalos da região semiárida do Brasil

Abstract Brazilian spotted fever (BSF) is a common tick-borne disease caused by Rickettsia rickettsii. Horses are the primary hosts of the main vector, Amblyomma sculptum, and are considered efficient sentinels for circulation of Rickettsia. Therefore, the aim of this study was to detect antibodies reactive to R. rickettsii antigens in horses from a non-endemic area in the north-central region of Bahia state, Brazil. Blood samples and ticks were collected from 70 horses from the municipalities of Senhor do Bonfim, Antônio Gonçalves, Pindobaçu, and Campo Formoso. The sera obtained were tested by an indirect immunofluorescence assay to detect anti-Rickettsia antibodies. Overall, 5.7% (4/70) of the horses reacted to R. rickettsii antigens. Ticks were collected from 18.6% (13/70) of the horses and were identified as A. sculptum and Dermacentor nitens. Despite being a non-endemic area, seropositive animals were identified in our study, suggesting circulation of rickettsial agents in the region. This is the first serological survey of this agent in horses from the north-central region of Bahia, and further studies are needed to understand the epidemiology of BSF in these locations.

Resumo A Febre Maculosa Brasileira (FMB) é uma importante zoonose causada por Rickettsia rickettsii, sendo seu vetor o Amblyomma sculptum. Cavalos são os principais hospedeiros desse carrapato e considerados sentinelas eficientes para detectar a circulação de Rickettsia. O objetivo deste estudo foi detectar anticorpos reativos a antígenos de R. rickettsii em cavalos de uma área não-endêmica na região Centro-Norte da Bahia, Brasil. Foram coletadas amostras de sangue e carrapatos de 70 cavalos nos municípios de Senhor do Bonfim, Antônio Gonçalves, Pindobaçu e Campo Formoso. Os soros obtidos foram testados pela reação de imunofluorescência indireta para detectar anticorpos anti-Rickettsia. No geral, 5,7% (4/70) dos cavalos reagiram sorologicamente para antígenos de R. rickettsii. Os carrapatos foram coletados em 18,6% (13/70) dos cavalos e foram identificados como A. sculptum e Dermacentor nitens. Embora seja uma área não endêmica, foram observados animais soropositivos, sugerindo a circulação de riquétsias na região estudada. Este é o primeiro estudo de levantamento sorológico desse agente em cavalos do Centro-Norte da Bahia. São necessários mais estudos para compreender a epidemiologia da FMB nesses locais.

Free-living capybaras (Hydrochoerus hydrochaeris) in an urban area in Brazil: biochemical and hematological parameters

Capybaras have found favorable conditions for survival and reproduction in green urban environments. In recent years, the population of these large rodents has been increasingly abundant in several brazilian cities such as Uberlândia, a municipality of the southeastern region with a Cerrado biome. Capybaras are important in the Brazilian Spotted Fever epidemiological chain, by amplifying infection rates of the vector population. However, knowledge of this host's physiology is scarce. Thus, the aim of this work was to describe hematological and biochemical parameters of free-living capybaras groups in urbanized areas in the city of Uberlândia, Minas Gerais State, Brazil. Capybaras were captured in 4 different locations of Uberlândia city, Minas Gerais state, including 1 Condominium (P1), 1 Private Market Garden (P2), 1 Private Club (P3) and 1 Municipal Park (P4). The animals were baited into an octagonal iron corral and chemically contained with anesthetic darts. After sedated, blood was collected from the femoral vein in tubes with and without EDTA. Biochemical evaluation, hematological analysis with differential leukocyte counts and search for Dirofilaria sp. were done. The blood count and biochemistry values obtained from animals of different ages, sex and sectors (P1, P2, P3 and P4) were submitted to the Shapiro-Wilk normality test, considering 95% significance. Values that had a normal distribution were subjected to ANOVA tests followed by Student's t-test. Values that did not follow normality were submitted to the Kruskal-Wallis test, to obtain a P-value, with a significance level of 95%. A total of 19 capybaras were captured: 4 in P1, 6 in P2, 4 in P3 and 5 in P4. From the 19 animals, 13 were females (68.42%) and 6 were males (31.57%), 12 adults (63.15%) and 7 juveniles (36.84%). Apart from occasional skin scars and moderate to intense Ambyomma spp. tick infestations, all captured animals were healthy on a broad examination. From 5 animals captured in P4, despite the use of anticoagulant, blood from 4 animals clotted fast. No microfilariae were found in the thick drop test in any of the 19 animals sampled, and in 2 adult female capybaras captured in P1, Kurloff cells were observed. Hematological and biochemical values presented no major differences when comparing sex and age. Nevertheless, differences in liver and kidney profile were observed between the capybara groups, including ALT, alkaline phosphorus, BUN and creatinine. Blood from 4 animals clotted fast, despite the use of EDTA tubes. Blood clotting of samples with anticoagulant in this work could be associated with some physiological features inherent to capybaras. Many attempts were required to obtain enough blood from each individual due to the rapid hemostasis, what come in accordance with reports in literature. Kurloff cells were observed in 2 adult female capybaras captured in P1, which can be found in peripheral blood of female rodents during follicular phase of estrous cycle. Hematological and biochemical values differences in liver enzymes such as ALT and alkaline phosphorus, and kidney profile enzymes including BUN and creatinine could be associated to capture stress or dietetic variation between groups. Despite statistical relevant, the values were still in accordance with other works, although comparisons should be done with caution since various environments exert a diverse array of stimulus upon the animals such as parasitic, infective, stress, nutritional, social and undoubtedly blood parameters mirror them. In conclusion, this work contributes to the standardization of free-living capybaras' physiological parameters in urban areas.(AU)

Perfil Epidemiológico da Febre Maculosa no Brasil / Epidemiological Profile of Spotted Fever in Brazil

Introdução: A Febre Maculosa é uma doença febril aguda, causada pela bactéria Rickettsia rickettsii e transmitida pela picada de carrapatos infectados. Atualmente, ocorre um aumento da incidência e das mortes pela doença em diversas áreas do Brasil, o que pode significar um surto e a necessidade de alerta. Metodologia: Estudo quantitativo, descritivo, transversal, que embasou sua busca nas plataformas de notificações brasileiras (DATASUS e SINAN) e boletins epidemiológicos no período de 2007 a 2019. Resultados: O número de casos e a mortalidade demonstraram valores maiores nos meses correspondentes à fase de ninfa do carrapato vetor, com incidência maior na zona rural, na região sudeste e durante o lazer. Além disso, a faixa etária mais atingida foi de 40 a 59 anos, com predominância da população masculina. Os valores maiores apresentados nas zonas rurais, assim como grupo etário e sexo se devem às atividades realizadas que expõem mais os indivíduos ao ambiente natural dos vetores, à sazonalidade dos carrapatos e à presença da Mata Atlântica. Nota-se a presença de grande subnotificação no Brasil. Conclusão: Constata-se a necessidade de desenvolver de políticas de prevenção e disseminar informações sobre o ciclo da doença, manifestações clínicas, prevenção e tratamento.

Introduction: Spotted Fever is an acute febrile disease, caused by the bacteria Rickettsia rickettsii and transmitted by the bite of infected ticks. Currently, there is an increase in the incidence and deaths from the disease in several areas of Brazil, which may mean an outbreak and the need for alert. Methodology: Quantitative, descriptive, cross-sectional study that based its search on the Brazilian notification platforms (DATASUS and SINAN) and newsletters. Results: The number of cases and mortality showed higher values in months corresponding to the vector tick nymph phase (from June to September), with a higher incidence in countryside, in southeast region and at moments of leisure practice. In addition, the most affected age group was 40 to 59 years old, in male population. Higher values presented in countryside, as well as age group and sex are due to activities that expose individuals more to natural environment of vectors, the seasonality of the ticks and the presence of the Atlantic Forest. In addition, there is a large underreporting in Brazil. Conclusion: It´s necessary to develop prevention policies, as well as disseminate information about disease cycle, clinical manifestations, prevention and treatment.

Detecção de anticorpos anti-Rickettsia rickettsii em cães residentes em área negligenciada no município de São Paulo, SP, Brasil / [Detection of anti-Rickettsia rickettsii antibodies in dogs living in a neglected area in São Paulo, SP, Brazil]

A febre maculosa brasileira (FMB), descrita inicialmente nos Estados Unidos como febre maculosa das Montanhas Rochosas, é uma antropozoonose relatada apenas no continente americano e causada pela bactéria Rickettsia rickettsii. No Brasil a transmissão ocorre sobretudo pela picada de carrapatos do gênero Amblyomma spp. A doença foi inicialmente descrita como de transmissão em áreas rurais e silvestres, no entanto áreas periurbanas e urbanas vêm apresentando casos, principalmente relacionados com a presença de humanos residindo em pequenos fragmentos de mata ciliar. O presente estudo teve por objetivo elucidar a dispersão da FMB nas proximidades dos reservatórios Guarapiranga e Billings, na cidade de São Paulo, SP. Para tanto, a presença de anticorpos anti-R. rickettsii, Rickettsia parkeri e Rickettsia bellii foi avaliada em cães atendidos nas campanhas de esterilização cirúrgica e residentes ao redor dos reservatórios. Foram coletadas amostras de 393 cães, e as amostras de soro foram analisadas pela reação de imunofluorescência indireta (RIFI), com ponto de corte de 1:64. Os títulos para R. rickettsii variaram de 256 a 4096, com positividade de 3,3% (13/393); para R. bellii, de 128 a 1024 e 4,1% (16/393) de positivos, e um único animal (0,25%) foi soropositivo para R. parkeri, com título de 128. Os achados permitem concluir que a região de estudo apresenta condições de se tornar uma possível área com casos de FMB, pois comporta fragmentação de Mata Atlântica, condições essas ideais para a manutenção do vetor do gênero Amblyomma já descrito na região, bem como para a presença da Rickettsia rickettsii circulante entre os cães, confirmada pela existência de anticorpos. Condutas referentes à conscientização da população por meio de trabalhos educacionais devem ser implantadas para a prevenção da doença na população da área.(AU)

Brazilian Spotted Fever (BSF), initially described in the United States as Rocky Mountain Spotted Fever, is an anthropozoonosis reported only in the Americas and caused by the bacterium Rickettsia rickettsii. In Brazil, transmission occurs mainly through tick bites of the genus Amblyomma spp. The disease was initially described as transmission of rural and wild areas; however, peri-urban and urban areas have been presenting cases, mainly related to the presence of humans residing in small fragments of riparian forest. The present study aimed to elucidate the dispersal of BSF near the Guarapiranga and Billings Reservoirs, in the city of São Paulo, SP. The presence of anti-R. rickettsii, Rickettsia parkeri and Rickettsia bellii antibodies were evaluated in dogs treated in surgical sterilization campaigns and residents around the Reservoirs. Samples were collected from 393 dogs and serum samples were analyzed by indirect immunofluorescence reaction (RIFI) with a cutoff of 1:64. The titles for R. rickettsii varied from 256 to 4096 with a positivity of 3.3% (13/393); for R. bellii from 128 to 1024 and 4.1% (16/393) of positive and a single animal (0.25%) was seropositive for R. parkeri with a titre of 128. The findings allow us to conclude that the study region has conditions to become a possible area with BSF cases, as it involves Atlantic Forest, ideal conditions for the maintenance of the vector of the genus Amblyomma already described in the region and the presence of circulating Rickettsia rickettsii among dogs, confirmed by the presence of antibodies. Conducts regarding the awareness of the population through educational work should be implemented to prevent the disease in the population of the area.(AU)

Selective fragmentation of the trans-Golgi apparatus by Rickettsia rickettsii.

Fragmentation of the Golgi apparatus is observed during a number of physiological processes including mitosis and apoptosis, but also occurs in pathological states such as neurodegenerative diseases and some infectious diseases. Here we show that highly virulent strains of Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever, induce selective fragmentation of the trans-Golgi network (TGN) soon after infection of host cells by secretion of the effector protein Rickettsial Ankyrin Repeat Protein 2 (RARP2). Remarkably, this fragmentation is pronounced for the trans-Golgi network but the cis-Golgi remains largely intact and appropriately localized. Thus R. rickettsii targets specifically the TGN and not the entire Golgi apparatus. Dispersal of the TGN is mediated by the secreted effector protein RARP2, a recently identified type IV secreted effector that is a member of the clan CD cysteine proteases. Site-directed mutagenesis of a predicted cysteine protease active site in RARP2 prevents TGN disruption. General protein transport to the cell surface is severely impacted in cells infected with virulent strains of R. rickettsii. These findings suggest a novel manipulation of cellular organization by an obligate intracellular bacterium to determine interactions with the host cell.

Rickettsial infection in equids, opossums and ticks in the municipality of Monte Mor, state of São Paulo, Brazil / Infecção por Rickettsia spp. em equídeos, gambás e carrapatos do município de Monte Mor, estado de São Paulo, Brasil

Abstract The aim of this study was to investigate rickettsial infection in equids, opossums and ticks in the municipality of Monte Mor, a place where a Brazilian spotted fever case occurred in 2005. In addition, characteristics possibly associated with seropositivity in horses were analyzed. Serum samples from horses, mules and opossums (Didelphis albiventris) were subjected to indirect immunofluorescence assay (IFA) against Rickettsia rickettsii. The ticks collected from the animals were identified and Amblyomma sculptum ticks from the equids were tested using PCR for Rickettsia spp. Anti-R. rickettsii antibodies were detected in 22.6% (14/62) of the horses, none of the mules and 21.7% (5/23) of the opossums. Among the variables analyzed, only age > 12 years showed a statistically significant association with seropositivity among horses. All of the 166 A. sculptum ticks tested using PCR were negative. The results showed that rickettsiae of the spotted fever group was circulating in the municipality of Monte Mor when the samples were collected and indicate a need for surveillance of Brazilian spotted fever in this region.

Resumo Este trabalho objetivou pesquisar a infecção por Rickettsia spp. em equídeos, gambás e carrapatos, do município de Monte Mor, local que teve um caso de febre maculosa brasileira, em 2005. Além disso, características possivelmente associadas com a soropositividade nos equinos foram analisadas. Soros de equinos, muares e gambás Didelphis albiventris foram submetidos à reação de imunofluorescência indireta (RIFI) contra Rickettsia rickettsii. Os carrapatos coletados dos animais foram identificados e os carrapatos Amblyomma sculptum dos equídeos foram testados pela PCR para Rickettsia spp. Anticorpos anti-R. rickettsii foram detectados em 22,6% (14/62) equinos, zero muares e 21,7% (5/23) gambás. Entre as variáveis analisadas, apenas a idade maior que 12 anos mostrou associação estatisticamente significante com a soropositividade em equinos. De 166 carrapatos A. sculptum testados pela PCR, todos foram negativos. Os resultados mostram que riquétsias do grupo da febre maculosa estavam circulando no município de Monte Mor, quando as amostras foram coletadas, e apontam para a necessidade de vigilância para a febre maculosa brasileira nessa região.

Fiebre manchada en Argentina. Descripción de dos casos clínicos / Spotted fever in Argentina. Description of two clinical cases

Resumen Las rickettsiosis son enfermedades zoonóticas transmitidas por artrópodos vectores, que en Argentina presentan 2 escenarios epidemiológicos diferenciados. Uno, en las yungas de Salta y Jujuy, involucra vectores pertenecientes al «complejo Amblyomma cajennense¼ (A. sculptum y A. toneliae) y a Rickettsia rickettsii como agente etiológico. En este escenario la forma clínica de la enfermedad se conoce como fiebre manchada (FM) y se presenta con manifestaciones cutáneas y sistémicas graves. El otro escenario incluye 2 zonas: una la del Delta del Río Paraná y Bahía de Samborombón, donde Amblyomma triste actúa como vector; otra, las provincias de Córdoba, La Rioja, San Luis y La Pampa, donde el vector es Amblyomma tigrinum. En este segundo escenario Rickettsia parkeri es el agente causal, y la FM se manifiesta con un cuadro benigno y autolimitado. En este trabajo describimos un caso fatal de FM por R. rickettsii en El Tunal, Salta, y el primer caso de FM por R. parkeri en San Juan.

Abstract Rickettsioses are zoonotic tick-borne diseases. In Argentina, there are two epidemiological scenarios: jungle of Salta and Jujuy, involving vectors from the "Amblyomma cajennense Complex" (A. sculptum, and A. toneliae) and Rickettsia rickettsii as the main etiological agent; and the second scene to Delta del Rio Paraná and Samborombón Bay, where Amblyomma triste acts as a vector; and the provinces of Córdoba, La Rioja, San Luis and La Pampa where Amblyomma tigrinum is the vector. In this second scenario, Rickettsia parkeri is the causal agent. The spotted fever (SF) due to R. rickettsii is responsible for a severe cutaneous and systemic disease. Contrarily, R. parkeri produces benign and self-limited clinical manifestation. Here we describe a fatal SF case by R. rickettsii, in El Tunal, Salta and the first SF case due to R. parkeri in San Juan.

HLA-B27 spondyloarthritis and spotted fever rickettsiosis: case-based review.

Rickettsia rickettsii, a tick borne disease, is the pathogen responsible for inducing Rocky Mountain Spotted Fever (RMSF), an illness that can progress to fulminant multiorgan failure and death. We present a case where R. rickettsii, acquired on a camping trip, precipitated a flare of peripheral arthritis and episcleritis in an HLA-B27 positive patient. Although Yersinia, Salmonella, Mycobacteria, Chlamydia, Shigella, Campylobacter, and Brucella have been previously associated with HLA-B27 spondyloarthritis, this unusual case demonstrates that obligate intracellular rickettsial organisms, and specifically, R. rickettsii, can also induce flares of HLA-B27 spondyloarthritis. Rickettsial infections in general can rapidly become fatal in both healthy and immunosuppressed patients, and thus, prompt diagnosis and therapy are required.

Respecto a un caso de rickettsia rickettsii en Costa Rica / Regarding a rickettsia rickettsii case in Costa Rica

Resumen Las rickettsiosis representan una zoonosis de etiología bacteriana intracelular, las cuales son transmitidas por vectores como artrópodos a la piel y luego a las células endoteliales microvasculares. La Fiebre de las Montañas Rocosas (FMMR) causada por Rickettsiarickettsiies la más grave, y es una enfermedad reportada en Costa Rica desde 1977, que causa daño endotelial directo asociado a liberación de citocinasproinflamatorias y estrés oxidativo, lo que lleva a un proceso de vasculitis de pequeño y mediano vaso. La enfermedad se manifiesta clínicamente por fiebre acompañada de cefalea y mialgias, síntomas gastrointestinales y un brote cutáneo. El diagnóstico es basado en la clínica, la exposición a vectores y el respaldo de ensayos de laboratorio; y las tetraciclinas son su tratamiento de elección. El objetivo del presente trabajo es documentar un caso clínico confirmado de Fiebre Manchada de las Montañas Rocosas en Costa Rica, para evidenciar la importancia de considerar esta entidad como un diagnóstico diferencial en un síndrome febril agudo.

Abstract Rickettsiosis represents a zoonosis of intracellular bacterial etiology, which is transmitted by vectors such as arthropods to the skin and then to microvascular endothelial cells. Rocky Mountain Fever caused by Rickettsia rickettsii is the most serious, and it is a disease reported in Costa Rica since 1977. It causes direct endothelial damage associated with the release of proinflammatory cytokines and oxidative stress, which leads to a vasculitis of the small and medium vessels. The disease is manifested clinically by fever headache, myalgias, gastrointestinal symptoms and a cutaneous rash. The diagnosis is based on clinical manifestations, exposure to vectors and the support of laboratory tests; and tetracyclines are the treatment of choice. The objective of this work is to document a case of a Rocky Mountain Spotted Fever in Costa Rica, to demonstrate the importance of considerate this entity as a differential diagnosis in an acute febrile syndrome.

Long term neurologic sequelae in a Mexican rocky mountain spotted fever case

ABSTRACT During the second half of the twentieth century, neurologic sequelae associated with central nervous system impairment caused by Rickettsia rickettsii were studied widely and exclusively in the United States. We present the case of a Mexican pediatric patient with neurologic sequelae 10 years after an acute infection by R. rickettsii.

Características clínicas y para clínicas de los pacientes con fiebre manchada por Ricketts ia ricketts ii en Panamá (1950­-1951; 2004­-2017) / Clinical and para clinical characteristics of patients with fevers potted by Rickettsiarickettsii in Panama (1950­1951; 2004­2017)

La fiebre manchada causada por Ric ketts ia ric ketts iies por mucho la enfermedad transmitida por garrapatas más importante en América Latina y una de las zoonosis más relevante del continente. En Panamá esto es notorio si se considera que los casos confirmados de la misma se han registra­ do en dos series: 1950­1951, donde se presentaron cinco casos, donde los dos primeros fueron re­ sultaron fatales, y de 2004­2017, donde se confirmaron 10 casos, con nueve fallecimientos. A pes ar de lo anterior, la fiebre manchada causada por Rrickettsii es una enfermedad de baja preva­lencia y está dentro de las enfermedades desatendidas. El diagnóstico oportuno de Rrickettsii en personas afectadas por la misma, incrementa la posibilidad de sobrevivencia del paciente; sin em­bargo, a pesar de su alto porcentaje de mortalidad, esta enfermedad es poco reconocida y no se cuenta con sospecha clínica. Con el objetivo de presentar sus características clínicas en Panamá, se analizan individualmente cada reportes de caso, incluyendo datos etarios , de localidad, sínto­mas descritos, análisis aplicados y tratamiento.

The spotted fever caused by Ric ketts ia rickettsii is by far the most important tick­borne disease in Latin America and one of the most important zoonoses in the continent. In Panama this is notorious if it is considers that the confirmed cases have been registered in two series: 1950­1951, with five cas es and two fatal; and 2004­2017, with 10 cases and nine deaths. Despite the above, spotted fe­ver caused by R. rickettsii is a disease of low prevalence and is among the neglected diseases. The timely diagnosis of Rrickettsii in people affected by it, increases the possibility of survival of the pa­tient; however, despite its high mortality rate, this disease is poorly recognized and there is no clini­ cal suspicion. In order to present their clinical characteristics in Panama, each reports of case is analyzed individually, including age, location, symptoms described, applied analysis and treatmen

Fiebre manchada de montañas rocosas: experiencia en 5 años de vigilancia activa en un hospital pediátrico de segundo nivel en el noreste de México / Rocky mountain spotted fever: five years of active surveillance experience in a second level pediatric hospital in northeastern Mexico

Resumen: Introducción: La fiebre manchada de las montañas rocosas (FMMR) es causada por Rickettsia rickettsii. En Coahuila, la región de la Comarca Lagunera se considera una zona endémica. No se han reportado casos en la zona sur del estado, específicamente en la ciudad de Saltillo. Métodos: Estudio prospectivo, reporte de casos. Se incluyeron los casos de niños atendidos en el Hospital del Niño Dr. Federico Gómez Santos en la ciudad de Saltillo, Coah., del mes de septiembre de 2012 a septiembre 2017 con diagnóstico confirmado clínicamente y por reacción en cadena de la polimerasa (PCR) de FMMR. Se presentan los antecedentes epidemiológicos, las características clínicas y evolución de los pacientes. Resultados: Se confirmaron 14 pacientes. La relación masculino:femenino fue de 1.8:1, la edad promedio de los pacientes fue de 7.6 años (18 meses a 13 años). El 42.8% de los pacientes refirió el contacto con perros y el 57.1% afirmó tener contacto con garrapatas. En todos los casos hubo fiebre y exantema purpúrico; alrededor del 70% manifestaron mialgias y artralgias; el 28% tuvo sangrado del tubo digestivo, y el 11% alteraciones neurológicas graves. El 64.2% de los casos recibió tratamiento adecuado con doxiciclina. Fallecieron 8 pacientes, con una tasa de letalidad de 57.1%. Conclusiones: La zona sur de Coahuila debe considerarse una zona endémica para FMMR. El retraso en el diagnóstico y tratamiento favorecen una mayor letalidad.

Abstract: Background: Rocky Mountain Spotted Fever (RMSF) is caused by Rickettsia rickettsii. In Coahuila, Comarca Lagunera is considered an endemic zone; no cases have been reported in the southern zone of the state, specifically in the city of Saltillo­. Methods: Prospective study, cases report. Children evaluated in the Hospital del Niño Dr. Federico Gómez Santos from September 2012 to September 2017, with clinically and laboratory (by polymerase chain reaction, PCR) confirmed diagnosis of FMMR were included. The epidemiological antecedents, clinical characteristics and patient's evolution are presented. Results: 14 patients were confirmed. The male: female ratio was 1.8: 1, the average age of the patients was 7.6 years (18 months to 13 years). 42.8% reported contact with dogs and 57.1% confirmed contact with ticks. In all cases, there was fever and purpuric rash; around 70% manifested myalgias and arthralgias; 28% presented digestive tract bleeding and 11% had severe neurological alterations. 64.2% of the cases received adequate treatment with doxycycline. Eight patients died with a case fatality rate of 57.1%. Conclusions: The southern zone of Coahuila should be considered an endemic area for FMMR. The delay in diagnosis and treatment favor a greater lethality.

Fiebre manchada de evolución fatal en la provincia de Salta / Fatal spotted fever in Salta province

Describimos el caso de un varón de 17 años oriundo de la ciudad de Salta quien, 10 días después de visitar una zona rural de la provincia homónima, ingresó a nuestro hospital por convulsiones febriles. Durante la internación presentó exantema seguido de disfunción orgánica múltiple, la que evolucionó rápidamente hacia shock séptico irreversible y muerte a las 48 horas de su admisión. El diagnóstico serológico -altos títulos de IgM e IgG anti-Rickettsia spp. por inmunofluorescencia indirecta- arribó post mortem. Las rickettsiosis del grupo de las fiebres manchadas son transmitidas por garrapatas, tienen distribución global y en varios países continúan siendo subdiagnosticadas debido a una baja sospecha clínica. En las provincias del noroeste argentino se agrega la carencia de un laboratorio regional capacitado para efectuar el diagnóstico etiológico. Esta limitación es crítica porque en esa región del país ya ha sido documentada la presencia de las formas graves de la enfermedad, usualmente debidas a R. rickettsii. Dado que las fiebres manchadas se presentan como sindromes febriles inespecíficos y los componentes del ciclo enzoótico están presentes en vastas áreas geográficas, incluso en algunas aún no consideradas endémicas para rickettsiosis, su diagnóstico nunca debe ser subestimado. Con el tratamiento antibiótico adecuado instaurado en tiempo oportuno, el pronóstico de este grupo de enfermedades potencialmente mortales mejora en forma drástica.

We describe the case of a 17-year-old male patient living in Salta city who, 10 days after visiting a rural area in Salta province, was hospitalized for febrile seizures. Shortly after admission, he developed an exanthema followed by a multiple organ dysfunction that evolved to irreversible septic shock followed by death 48 hours after admission. Serological diagnosis -high IgM and IgG anti-Rickettsia spp. antibody titres as detected by indirect immunofluorescence- arrived post mortem. Spotted fever group rickettsioses are tick-borne diseases distributed worldwide and continue being under diagnosed in several countries mainly due to a low clinical suspicion. In the north-western provinces of Argentina there is also the limitation of not counting with a regional laboratory to perform the etiological diagnosis. This is crucial because the severe forms of the disease, which are commonly caused by R. rickettsii, have been already documented in the region. Given that spotted fevers have broadly unspecific febrile presentations and the components of the enzootic cycle are present even in geographic areas not yet considered to be endemic for tick borne diseases, their diagnosis should not be underestimated. If the adequate antibiotic treatment is administered timely, the prognosis of this group of life-threatening diseases improves drastically.