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.

Tick-borne illnesses: identification and management in the emergency department

Tick-borne illnesses are increasing in prevalence and geographic reach. Because the presentation of these illnesses is sometimes nonspecific, they can often be misdiagnosed, especially in the early stages of illness. A detailed history with questions involving recent activities and travel and a thorough physical examination will help narrow the diagnosis. While some illnesses can be diagnosed on clinical findings alone, others require confirmatory testing, which may take days to weeks to result. This issue reviews the emergency department presentation of 9 common tick-borne illnesses and evidence-based recommendations for identification, testing, and treatment.

Chemical identification of Tagetes minuta Linnaeus (Asteraceae) essential oil and its acaricidal effect on ticks / Caracterização química e efeito acaricida do óleo essencial de Tagetes minuta Linnaeus (Asteraceae) em carrapatos

The control of tick species that affect animal production is vital for the economic welfare of the cattle industry. This study focused on testing the acaricidal activity of the essential oil from the leaves and stems of Tagetes minuta against several Brazilian tick species, including Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineus, Amblyomma cajennense and Argas miniatus. The chemical composition of the essential oil was determined by chromatography and spectroscopy analyses, which revealed the presence of monoterpenes. The adult immersion test (AIT) and the larval packet test (LPT) were used to evaluate the efficacy of T. minuta essential oil in tick management at concentrations of 2.5, 5, 10, 20 and 40%. The results demonstrated that the T. minuta essential oil had over 95% efficacy against four species of ticks at a concentration of 20%. These results suggest that the essential oil of T. minuta could be used as an environmentally friendly acaricide.(AU)

O controle de carrapatos que causa impacto na produção de bovinos possui importância econômica para a cadeia produtiva. Neste trabalho objetivou-se testar a atividade acaricida do óleo essencial das folhas e caules de Tagetes minuta contra várias espécies de carrapatos brasileiros, incluindo Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineus, Amblyomma cajennense e Argas miniatus. A composição química do óleo foi determinada por GC-MS e análises de espectroscopia de RMN, que revelaram a presença de monoterpenos. Na avaliação destas substâncias no controle do carrapato foram empregados os testes de imersão de adulto (TIA) e o de pacote de larvas (TPL) para o extrato de óleo de T. minuta nas concentrações de 2,5%; 5%; 10%; 20% e 40%. Os resultados do TPL e TIA demonstraram que o óleo essencial na concentração de 20% de T. minuta apresenta eficácia superior a 95% nas quatro espécies de carrapato. Estes resultados sugerem que o óleo essencial de T. minuta pode ser usado como um acaricida eficaz e com baixo impacto ambiental.(AU)

[Brazilian lyme-like disease or Baggio-Yoshinari syndrome: exotic and emerging Brazilian tick-borne zoonosis].

Lyme disease (LD) is a frequent zoonosis found in the Northern Hemisphere and is considered an infectious disease caused by spirochetes belonging sensu lato to the Borrelia burgdorferi complex transmitted by ticks of the Ixodes ricinus group. In 1992, first cases similar to LD were described in Brazil, when brothers, after a tick bite episode developed symptoms , as erythema migrans, general flu-like symptoms and arthritis. Careful analysis of Brazilian LD-like illness casuistry showed that epidemiological, clinical and laboratorial features in the country were very different from those exhibited by North American and Eurasian LD patients. Human blood-suckers Ixodes ricinus complex ticks were absent at risk areas; the disease is recurrent in the country; Borrelia burgdorferi was never isolated in Brazil and specific serologic tests have shown little positivity with inconsistent results. Furthermore, peripheral blood analysis of patients on electron microscopy exhibited structures resembling Mycoplasma spp, Chlamydia spp and spirochete-like microorganisms. In fact, they were assumed to be latent forms of spirochetes (L form or cell wall deficient bacteria) adapted to survive at inhospitable conditions in vertebrate and invertebrate hosts. For these reasons, the Brazilian zoonosis was named Baggio-Yoshinari Syndrome (BYS) and defined as: "Exotic and emerging Brazilian infectious disease, transmitted by ticks not belonging to the Ixodes ricinus complex, caused by latent spirochetes with atypical morphology, which originates LD-like symptoms, except for occurrence of relapsing episodes and auto-immune disorders".

Doença de lyme-símile brasileira ou síndrome baggioyoshinari: zoonose exótica e emergente transmitida por carrapatos: [revisão] / Brazilian lyme-like disease or baggio-yoshinari syndrome: exotic and emerging brazilian tick-borne zoonosis: [review]

A Doença de Lyme (DL) é uma zoonose frequente no hemisfério Norte e considerada uma enfermidade infecciosa causada por espiroquetas do complexo Borrelia burgdorferi sensu lato e transmitida pela picada de carrapatos do grupo Ixodes ricinus. Os primeiros casos semelhantes à DL no Brasil foram descobertos, em 1992, em irmãos que após serem picados por carrapatos desenvolveram eritema migratório, sintomas gripais e artrite. Criteriosa análise da casuística brasileira, mostrou que os aspectos epidemiológicos, clínicos e laboratoriais no país, divergiam bastante dos exibidos pelos pacientes com DL nos Estados Unidos da América e Eurásia. Não foram encontrados carrapatos do complexo Ixodes ricinus hematófago ao homem nas áreas de risco; a enfermidade no país é recorrente; a Borrelia burgdorferi jamais foi isolada no Brasil e os ensaios sorológicos específicos exibem positividade baixa e oscilante. Além disso, o exame do sangue periférico dos pacientes quando analisados à microscopia eletrônica exibe estruturas sugestivas de Mycoplasma spp, Chlamydia spp e bacteroides. Na verdade, estas estruturas podem representar as formas latentes das espiroquetas (forma L ou bactérias desprovidas de parede), adaptadas a sobreviver em condições inóspitas em hospedeiros vertebrados e invertebrados. Assim, a zoonose presente no país recebeu a denominação de Síndrome Baggio-Yoshinari e definida como: "Enfermidade infecciosa nova e emergente brasileira, transmitida por carrapatos não pertencentes ao complexo Ixodes ricinus, causada por espiroquetas na sua morfologia atípica e latente, que origina manifestações clínicas semelhantes às observadas na DL, exceto pela ocorrência de recidivas clínicas e desordens autoimunes".

Lyme disease (LD) is a frequent zoonosis found in the Northern Hemisphere and is considered an infectious disease caused by spirochetes belonging sensu lato to the Borrelia burgdorferi complex transmitted by ticks of the Ixodes ricinus group. In 1992, first cases similar to LD were described in Brazil, when brothers, after a tick bite episode developed symptoms , as erythema migrans, general flu-like symptoms and arthritis. Careful analysis of Brazilian LD-like illness casuistry showed that epidemiological, clinical and laboratorial features in the country were very different from those exhibited by North American and Eurasian LD patients. Human blood-suckers Ixodes ricinus complex ticks were absent at risk areas; the disease is recurrent in the country; Borrelia burgdorferi was never isolated in Brazil and specific serologic tests have shown little positivity with inconsistent results. Furthermore, peripheral blood analysis of patients on electron microscopy exhibited structures resembling Mycoplasma spp, Chlamydia spp and spirochete-like microorganisms. In fact, they were assumed to be latent forms of spirochetes (L form or cell wall deficient bacteria) adapted to survive at inhospitable conditions in vertebrate and invertebrate hosts. For these reasons, the Brazilian zoonosis was named Baggio-Yoshinari Syndrome (BYS) and defined as: "Exotic and emerging Brazilian infectious disease, transmitted by ticks not belonging to the Ixodes ricinus complex, caused by latent spirochetes with atypical morphology, which originates LD-like symptoms, except for occurrence of relapsing episodes and auto-immune disorders".