Rickettsias del grupo de las fiebres manchadas en garrapatas del género Amblyomma, capaces de infestar humanos, en áreas rurales del noroeste de Argentina

This work was performed to detect Rickettsia species of the spotted fever group in Amblyomma ticks likely to infest humans in rural areas from northwestern Argentina. Free-living ticks were collected and determined as Amblyomma tigrinum, Amblyomma neumanni and Amblyomma tonelliae. Rickettsia infection was determined by polymerase chain reactions which amplify fragments of the rickettsial genes gltA and ompA. A high frequency (35/44, 79.5%) of Candidatus “Rickettsia andeanae” was observed in A. tigrinum ticks, and Candidatus “Rickettsia amblyommii” was found in three out of 14 nymphs of A. neumanni. All 14 Amblyomma tonelliae ticks were negative for rikettsiae. The infection with spotted fever group rickettsiae in ticks aggressive for humans reveals the potential risk of exposure to tick-borne pathogens of people inhabiting rural areas of northwestern Argentina.Fil: Saracho Bottero, María Noelia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Tarragona, Evelina Luisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Nava, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentin

Birds and hard ticks (Acari: Ixodidae), with discussions about hypotheses on tick evolution

The relationship between birds (Aves) and hard ticks (Ixodidae) was analyzed for the 386 of 721 tick extant species whose larva, nymph and adults are known as well as their natural hosts. A total of 136 (54 Prostriata= Ixodes, 82 Metastriata= all other genera) are frequently found on Aves, but only 32 species (1 associated with Palaeognathae, 31 with Neognathae) have all parasitic stages feeding on birds: 25 Ixodes (19% of the species analyzed for this genus), 6 Haemaphysalis (7%) and 1 species of Amblyomma (2%). The species of Amblyomma feeds on marine birds (MB), the six Haemaphysalis are parasites of non-marine birds (NMB), and 14 of the 25 Ixodes feed on NMB, one feeds on NMB and MB, and ten on MB. The Australasian Ixodes + I. uriae clade probably originated at an uncertain time from the late Triassic to the early Cretaceous. It is speculated that Prostriata first hosts were Gondwanan theropod dinosaurs in an undetermined place before Pangaea break up; alternatively, if ancestral monotromes were involved in its evolution an Australasian origin of Prostriata seems plausible. As for Prostriata the Motherland of Ixodida is probably Gondwana.Aves y garrapatas duras (Ixodidae), con discusión sobre hipótesis sobre evolución de las garrapatas. En esta revisión se analizó la relación entre aves y garrapatas duras (Ixodidae) para las 386 de 725 especies de garrapatas que utilizan aves como hospedadores para larvas, ninfas y adultos. Un total de 136 especies (54 Prostriata= Ixodes, 82 Metastriata= restantes géneros) son frecuentemente encontradas sobre aves, pero solo 32 especies (1 asociada con Palaeognathae, 31 con Neognathae) tienen ciclos donde todos los estadios se alimentan sobre aves: 25 Ixodes (19% de las especies analizadas para este género), 6 Haemaphysalis (7% del total) y 1 especie de Amblyomma (2% del total). Las especies de Amblyomma se alimentan sobre aves marinas (MB), las seis de Haemaphysalis son parásitas de aves no-marinas (NMB), y 14 de las 25 especies de Ixodes se alimentan sobre NMB, una sobre NMB y MB, y diez sobre MB. El clado de Australasia Ixodes + I. uriae probablemente se originó entre el fin del Triásico y comienzos del Cretácico. Se especula que los primeros hospedadores de Prostriata fueron dinosaurios terópodos con distribución Gondwánica; alternativamente, si monotremas ancestrales estuvieron involucrados en su evolución, un origen de Prostriata en Australasia es plausible. Al igual que para Prostriata, el área de origen de Ixodida es probablemente GondwanaEEA RafaelaFil: Guglielmone, Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nava, Santiago. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Rodents of the subfamily Sigmodontinae (Myomorpha: Cricetidae) as hosts for South American hard ticks (Acari: Ixodidae) with hypotheses on life history

Historical information shows that Sigmodontinae are irrelevant hosts for South American ticks of the genera Haemaphysalis Koch, Rhipicephalus Koch and Dermacentor Koch. Nine Amblyomma Koch species were found on Sigmodontinae but only Amblyomma triste Koch, 1844 appears strongly related to them. Eighteen species of Ixodes Latreille were determined on these hosts. Four species sporadically infest Sigmodontinae; eight are found mostly on Sigmodontinae but the records are too few for any inference. Six: I. amarali Fonseca, 1935, I. longiscutatus Boero, 1944, I. loricatus Neumann, 1899, I. luciae Sénevet, 1940, Ixodes sigelos Keirans, Clifford and Corwin, 1976 and I. venezuelensis Kohls, 1953 are usual parasites of Sigmodontinae. It is proposed that the Ixodes-Sigmodontinae relationship evolved from a South American tick ancestor parasite of Didelphidae. Their descendants are two extant clades, one formed by I. loricatus-I. luciae defined by analysis of 16S rDNA sequences further including I. amarali and I. schulzei by morphological affinities. These species (I. schulzei excluded) have adult ticks feeding on Didelphidae and sub-adult ticks feeding on Didelphidae and several species from five sigmodontin tribes. The second clade is formed by I. abrocomae Lahille, 1916 (known from few specimens, mostly collected from Sigmodontinae), I. sigelos (mainly a parasite of Sigmodontinae), I. stilesi Neumann, 1911 (parasite of deer), and possibly I. taglei Kohls, 1969 (parasite of deer) by morphological affinity. This clade is related to I. neuquenensis Ringuelet, 1947, an exclusive parasite of Dromiciops gliroides Thomas (Microbiotheriidae Ameghino).Fil: Guglielmone, Alberto Alejandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Nava, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentin

Hosts of Amblyomma dissimile Koch, 1844 and Amblyomma rotundatum Koch,1844 (Acari: Ixodidae)

Host records of Amblyomma dissimile Koch, 1844 and Amblyomma rotundatum Koch, 1844 from the literature were critically reviewed. A total of 417 records on 101 species of tetrapods, and 193 records in 74 species of tetrapods were determined for A. dissimile and A. rotundatum, respectively. Aves have been found only once infested with A. dissimile. This tick has been detected on four species of Bufonidae, while A. rotundatum has been recorded on 13 species from six families of Anura. Crocodilia has been recorded infested by A. rotundatum (captive host, one species) and A. dissimile (two species). Sixteen species of Mammalia from ten families and eight species from eight families have been found infested with A. dissimile and A. rotundatum, including humans, respectively. A total of 63 species of Squamata (10 families) were found infested with A. dissimile, while the corresponding numbers for A. rotundatum are 45 species in nine families. A total of 15 species of Testudines (four families) and nine species (three families) have been found infested with A. dissimile and A. rotundatum, respectively. When infestation on captive and laboratory hosts were excluded from the analysis the number of species naturally infested with A. dissimile diminished to 88 and 58 for A. rotundatum. However, natural hosts infested with larvae, nymphs and adults of A. dissimile are Bufo marinus (Linnaeus), Bufo peltocephalus Tschudi, Proechimys semispinosus (Tomes), Boa constrictor Linnaeus, Epicrates striatus (Fischer), Oxybelis aeneus (Wagler), Cyclura cychlura (Cuvier), Iguana iguana (Linnaeus), Tupinambis teguixin (Linnaeus) and Trachemys scripta (Thunberg), but the commonest hosts harbouring all parasitic stages are B. marinus, B. constrictor and /. iguana. Hosts for all parasitic stages of A. rotundatum are B. marinus, Bufo schneiden Werner and B. constrictor, although records on B. marinus are considerably higher than the records on the other two hosts. The contribution of sheep and Hydrochoerus hydrochaeris (Linnaeus) as hosts of A. dissimile, and Dasypus novemcinctus Linnaeus as host of A. rotundatum, were overestimated in previous studies. The ample host-range of these tick species may partly explain their wide distribution from southern U.S.A. to northern Argentina, but there are also chances that more than one species are represented under the names A. dissimile and A. rotundatum.Fil: Guglielmone, Alberto Alejandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Nava, Santiago. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentin

Hosts of Amblyomma dissimile Koch, 1844 and Amblyomma rotundatum Koch,1844 (Acari: Ixodidae)

Host records of Amblyomma dissimile Koch, 1844 and Amblyomma rotundatum Koch, 1844 from the literature were critically reviewed. A total of 417 records on 101 species of tetrapods, and 193 records in 74 species of tetrapods were determined for A. dissimile and A. rotundatum, respectively. Aves have been found only once infested with A. dissimile. This tick has been detected on four species of Bufonidae, while A. rotundatum has been recorded on 13 species from six families of Anura. Crocodilia has been recorded infested by A. rotundatum (captive host, one species) and A. dissimile (two species). Sixteen species of Mammalia from ten families and eight species from eight families have been found infested with A. dissimile and A. rotundatum, including humans, respectively. A total of 63 species of Squamata (10 families) were found infested with A. dissimile, while the corresponding numbers for A. rotundatum are 45 species in nine families. A total of 15 species of Testudines (four families) and nine species (three families) have been found infested with A. dissimile and A. rotundatum, respectively. When infestation on captive and laboratory hosts were excluded from the analysis the number of species naturally infested with A. dissimile diminished to 88 and 58 for A. rotundatum. However, natural hosts infested with larvae, nymphs and adults of A. dissimile are Bufo marinus (Linnaeus), Bufo peltocephalus Tschudi, Proechimys semispinosus (Tomes), Boa constrictor Linnaeus, Epicrates striatus (Fischer), Oxybelis aeneus (Wagler), Cyclura cychlura (Cuvier), Iguana iguana (Linnaeus), Tupinambis teguixin (Linnaeus) and Trachemys scripta (Thunberg), but the commonest hosts harbouring all parasitic stages are B. marinus, B. constrictor and /. iguana. Hosts for all parasitic stages of A. rotundatum are B. marinus, Bufo schneiden Werner and B. constrictor, although records on B. marinus are considerably higher than the records on the other two hosts. The contribution of sheep and Hydrochoerus hydrochaeris (Linnaeus) as hosts of A. dissimile, and Dasypus novemcinctus Linnaeus as host of A. rotundatum, were overestimated in previous studies. The ample host-range of these tick species may partly explain their wide distribution from southern U.S.A. to northern Argentina, but there are also chances that more than one species are represented under the names A. dissimile and A. rotundatum.Fil: Guglielmone, Alberto Alejandro. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Nava, Santiago. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentin

Infecção por riquétsias em carrapatos de aves silvestres em duas ecorregiões da Argentina

Several tick-borne Rickettsia species are recognized human pathogens in Argentina. Here we evaluated rickettsial infection in ticks collected on passerine birds during 2011-2012 in two eco-regions of Argentina. The ticks were processed by molecular analysis through polymerase chain reaction (PCR) detection and DNA sequencing of fragments of two rickettsial genes, gltA and ompA. A total of 594 tick specimens (532 larvae and 62 nymphs), representing at least 4 species (Amblyomma tigrinum, Ixodes pararicinus, Haemaphysalis juxtakochi, Haemaphysalis leporispalustris), were evaluated. At least one A. tigrinum larva, collected on Coryphospingus cucullatus in Chaco Seco, was infected with Rickettsia parkeri, whereas at least 12 larvae and 1 nymph of I. pararicinus, collected from Troglodytes aedon, Turdus amaurochalinus, Turdus rufiventris, C. cucullatus and Zonotrichia capensis, were infected with an undescribed Rickettsia agent, genetically related to several rickettsial endosymbionts of ticks of the Ixodes ricinus complex. R. parkeri is a recognized human pathogen in several American countries including Argentina, where a recent study incriminated A. tigrinum as the potential vector of R. parkeri to humans. Birds could play an important role in dispersing R. parkeri-infected A. tigrinum ticks. Additionally, we report for the first time a rickettsial agent infecting I. pararicinus ticks.Algumas espécies de Rickettsia transmitidas por carrapatos são reconhecidos como patógenos humanos na Argentina. Este presente trabalho avaliou a infecção por Rickettsia em carrapatos coletados em aves passeriformes, durante 2011-2012, em duas ecorregiões da Argentina. Os carrapatos foram processados pela reação em cadeia da polimerase (PCR) e sequenciamento de DNA de dois genes de Rickettsia: gltA e ompA. Ao todo, 594 amostras de carrapatos (532 larvas e 62 ninfas), representando pelo menos 4 espécies (Amblyomma tigrinum, Ixodes pararicinus, Haemaphysalis juxtakochi, Haemaphysalis leporispalustris), foram avaliadas. Pelo menos uma larva de A. tigrinum, coletada de Coryphospingus cucullatus no Chaco Seco, estava infectada com Rickettsia parkeri, enquanto pelo menos 12 larvas e 1 ninfa de I. pararicinus, coletadas de Troglodytes aedon, Turdus amaurochalinus, Turdus rufiventris, C. cucullatus e Zonotrichia capensis estavam infectadas com Rickettsia sp., geneticamente relacionada a vários endossimbiontes riquetsiais de carrapatos do complexo Ixodes ricinus. R. parkeri é reconhecidamente um patógeno humano em alguns países americanos, incluindo a Argentina, onde um estudo recente incriminou A. tigrinum como um provável vetor. Aves poderiam desempenhar um papel importante na dispersão de carrapatos A. tigrinum infectados por R. parkeri. Em adição, relata-se pela primeira vez a infecção por Rickettsia em I. pararicinus.Fil: Flores, Fernando Sebastián. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología “Dr. J. M. Vanella”; ArgentinaFil: Borges Costa, Francisco. Universidade de Sao Paulo; BrasilFil: Nava, Santiago. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Diaz, Luis Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología “Dr. J. M. Vanella”; ArgentinaFil: Labruna, Marcelo Bahía. Universidade de Sao Paulo; Brasi

Orden Acari: garrapatas

Las garrapatas son ectoparásitos hematófagos de vertebrados de las clases Amphibia, Reptilia, Aves y Mammalia. Se encuentran distribuidas desde los trópicos, donde está la mayor diversidad, hasta los dos polos. Junto con los mosquitos son los artrópodos vectores de agentes patógenos más relevantes. La importancia veterinaria, económica y para la salud pública de las garrapatas se debe a su capacidad y competencia vectorial para transmitir microorganismos patógenos como protozoos, rickettsias, espiroquetas y virus que afectan a los animales y al hombre, además de los efectos deletéreos causados por el parasitismo per se como disminución en la ganancia de peso en animales de producción en desarrollo, y el potencial para provocar toxicosis, parálisis, irritación y alergia a sus hospedadores. Las garrapatas son principalmente parásitos de animales silvestres, pero la baja especificidad por el hospedador de varias especies de este suborden deriva en diferentes patrones de infestación en humanos o animales de producción o compañía. Estas nuevas asociaciones parásito-hospedador se relacionan en gran medida a la introducción en un territorio particular de animales domésticos o exóticos, y a los disturbios ambientales por causas antrópicas. A nivel mundial existen alrededor de 984 especies válidas de garrapatas: 762 de la familia Ixodidae, 221 de Argasidae y una de Nuttalliellidae. En Argentina se han registrado hasta el momento 43 especies de la familia Ixodidae distribuidas en cinco géneros (25 de Amblyomma, una de Dermacentor, dos de Haemaphysalis, 12 de Ixodes y tres de Rhipicephalus) y 13 de la familia Argasidae pertenecientes a tres géneros (cinco de Argas, siete de Ornithodoros y una de Otobius). Las tres especies del género Rhipicephalus presentes en Argentina no son endémicas de la región Neotropical, sino que han sido introducidas desde el viejo mundo con el transporte de ganado bovino y perros.Facultad de Ciencias Naturales y Muse

Anatomical distribution of Rhipicephalus sanguineus sensu stricto (Acari: Ixodidae) on dogs

En este trabajo se realizó el estudio de la distribución anatómica de los diferentes estadios de Rhipicephalus sanguineus sensu stricto sobre sus hospedadores principales, los caninos. El mismo se basó en muestreos mensuales durante tres años en la ciudad de Esperanza, Santa Fe, Argentina. Para determinar la distribución de los diferentes estadios parasitarios se dividió el cuerpo en regiones y se colectaron todos los especímenes en cada una de ellas. Las larvas tuvieron como preferencia las zonas de cabeza seguido de los espacios interdigitales, orejas y abdomen; las ninfas tuvieron preferencia por las orejas y abdomen, y otras zonas de preferencia fueron cabeza y espacios interdigitales; los adultos (machos y hembras) prefirieron localizarse en las orejas, cuello y lomo.The anatomical distribution of the different stages of Rhipicephalus sanguineussensu stricto on canines was analyzed. Data was collected from dogs on monthly sampling during three years in the city of Esperanza, Santa Fe, Argentina. To determine the distribution of the different parasitic stages, the body surface was divided into regions and all specimens were counted in each of them. Larvae had preference for the head followed by the interdigital spaces, ears and abdomen, nymphs were mainly found on ears and abdomen, and other areas of preference were head and interdigital spaces; the adults (males and females) preferred the ears, neck and back.Fil: Nava, Santiago. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación de la Cadena Láctea. - Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela. Instituto de Investigación de la Cadena Láctea; Argentin

Sistemática y bioecología de Amblyomma neumanni Ribaga, 1902 y Amblyomma parvum Aragâo, 1908 [Acari: Ixodidae] en Argentina

Tesis presentada para optar al Grado de Doctor en Ciencias NaturalesFil: Nava, Santiago. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentin

Nuevos registros de garrapatas (Acari: Ixodidae) asociadas a roedores sigmodontinos en Chubut, Argentina

Se reportan nuevos hallazgos de garrapatas obtenidas de roedores capturados en sitios cercanos a Cholila (42o31'S, 71o27'W), provincia del Chubut (Argentina). Se registraron las siguientes asociaciones parásito-hospedador: Oligoryzomys lonngicaudatus: 1 larva de Amblyomma tigrinum, 1 hembra de Ixodes sigelos, 2 ninfas de I. sigelos; Reithrodon auritus: 1 hembra de I. sigelos; Loxodontomys micropus: 1 ninfa de I. sigelos; Chelemys macronyx: 7 larvas de I. sigelos. Ixodes sigelos no ha sido reportada previamente en C. macronyx, así como tampoco A. tigrinum sobre O. longicaudatus. Estos resultados brindan nueva evidencia del rol fundamental que cumplen los roedores en el ciclo biológico de algunas garrapatas presentes en la Argentina.We report new findings of ticks from rodents trapped at different sites near Cholila (42o31’S, 71o27’W), Chubut Province (Argentina). The following host-parasite associations were recorded: Oligoryzomys longicaudatus: 1 larva of Amblyomma tigrinum, 1 female of Ixodes sigelos, 2 nymphs of I. sigelos; Reithrodon auritus: 1 female of I. sigelos; Loxodontomys micropus: 1 nymph of I. sigelos; Chelemys macronyx: 7 larvae of I. sigelos. Ixodes sigelos has not been previously reported on C. macronyx as well as not A. tigrinum on O. longicaudatus. These results provide new evidence about the fundamental role of rodents in the life cycle of some ticks present in Argentina.Fil: Mastropaolo, Mariano. Universidad Nacional del Litoral; ArgentinaFil: Martin, Gabriel Mario. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nava, Santiago. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Santa Fe. Estacion Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin