| ecological aspects of four species of ticks found on cattle in salta, northwest argentina. | the seasonal activity of amblyomma cajennense, amblyomma neumanni, amblyomma parvum and boophilus microplus on cattle was studied in a ranch located in the northern part of the phytogeographical district of the chaco serrano where the habitat had suffered minimal human disturbance. the female ticks on one side of 10-25 cows were counted at intervals of 20-50 days from 29 october 1985 to 5 november 1986. the percentage of cattle parasitized with larvae and nymphs of amblyomma was recorded, along ... | 1990 | 2343535 |
| rickettsia parkeri in argentina. | clinical reports of an eschar-associated rickettsiosis in the paraná river delta of argentina prompted an evaluation of amblyomma triste ticks in this region. when evaluated by pcr, 17 (7.6%) of 223 questing adult a. triste ticks, collected from 2 sites in the lower paraná river delta, contained dna of rickettsia parkeri. | 2008 | 19046514 |
| detection of "candidatus rickettsia sp. strain argentina"and rickettsia bellii in amblyomma ticks (acari: ixodidae) from northern argentina. | ixodid ticks were collected from vegetation and from humans, wild and domestic mammals in a rural area in the semi-arid argentine chaco in late spring 2006 to evaluate their potential role as vectors of spotted fever group (sfg) rickettsiae. a total of 233 adult ticks, identified as amblyomma parvum, amblyomma tigrinum and amblyomma pseudoconcolor, was examined for rickettsia spp. we identified an sfg rickettsia of unknown pathogenicity, "candidatus rickettsia sp. strain argentina", in a. parvum ... | 2010 | 20186466 |
| vector potential and population dynamics for amblyomma inornatum. | we studied the natural life cycle of amblyomma inornatum and its vector potential in south texas. this tick is distributed throughout south texas and most of central america. a. inornatum represented 1.91% of the ticks collected by carbon dioxide traps during a study of free-living ticks in the tamaulipan biotic province in south texas. the life cycle of a. inornatum in south texas showed a clear seasonal pattern consistent with one generation per year. nymphs emerged in the spring with a peak i ... | 2015 | 25881916 |
| update on tick-borne rickettsioses around the world: a geographic approach. | tick-borne rickettsioses are caused by obligate intracellular bacteria belonging to the spotted fever group of the genus rickettsia. these zoonoses are among the oldest known vector-borne diseases. however, in the past 25 years, the scope and importance of the recognized tick-associated rickettsial pathogens have increased dramatically, making this complex of diseases an ideal paradigm for the understanding of emerging and reemerging infections. several species of tick-borne rickettsiae that wer ... | 0 | 24092850 |
| spotted fever group rickettsiae in amblyomma ticks likely to infest humans in rural areas from northwestern 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. t ... | 2015 | 26707663 |
| bacteria of the genera ehrlichia and rickettsia in ticks of the family ixodidae with medical importance in argentina. | the aim of this study was to get an overview about the occurrence of bacteria from the genus ehrlichia and rickettsia in ixodid ticks with medical importance in argentina. therefore, in 2013 and 2014, free-living ticks were collected in different provinces of northern argentina. these ticks were determined as amblyomma sculptum, amblyomma neumanni, amblyomma parvum, amblyomma triste, amblyomma ovale, amblyomma tonelliae and haemaphysalis juxtakochi. all samples were tested to determine the infec ... | 2017 | 27812828 |
| rickettsia bellii infecting amblyomma sabanerae ticks in el salvador. | four amblyomma sabanerae ticks collected from a turtle (kinosternon sp.) in san miguel, el salvador, were found by molecular analysis to be infected by rickettsia bellii. we provide the first report of rickettsia bellii in central america, and the first report of a rickettsia species in el salvador. | 2012 | 23265378 |
| wide dispersal and possible multiple origins of low-copy-number plasmids in rickettsia species associated with blood-feeding arthropods. | plasmids are mobile genetic elements of bacteria that can impart important adaptive traits, such as increased virulence or antibiotic resistance. we report the existence of plasmids in rickettsia (rickettsiales; rickettsiaceae) species, including rickettsia akari, "candidatus rickettsia amblyommii," r. bellii, r. rhipicephali, and reis, the rickettsial endosymbiont of ixodes scapularis. all of the rickettsiae were isolated from humans or north and south american ticks. r. parkeri isolates from b ... | 2010 | 20097813 |
| ecology of amblyomma neumanni (acari: ixodidae). | the life cycle of amblyomma neumanni was described studying the seasonal distribution of free-living stages and parasitic phases during two consecutive years. development periods of engorged ticks under different photoperiod conditions were recorded. larvae of a. neumanni have the peak of abundance in autumn. nymphs reach the peak in winter. females were collected on cattle from autumn to late spring. the seasonal distribution pattern of females showed a bimodal curve, with a peak in autumn and ... | 2009 | 19427299 |
| infection by rickettsia bellii and candidatus "rickettsia amblyommii" in amblyomma neumanni ticks from argentina. | the tick species, amblyomma neumanni (acari: ixodidae) is the most frequent tick parasitizing humans in northwestern argentina. the present study evaluated the rickettsial infection among 55 a. neumanni adult free-living ticks collected in dean funes, córdoba province. ticks were individually processed by the hemolymph test with gimenez staining, isolation of rickettsia in vero cell culture by the shell vial technique, and polymerase chain reaction (pcr) targeting the citrate synthase rickettsia ... | 2007 | 17264991 |
| isolation of rickettsia rhipicephali and rickettsia bellii from haemaphysalis juxtakochi ticks in the state of são paulo, brazil. | in the present study, attempts to isolate rickettsia in cell culture were performed individually in seven specimens of haemaphysalis juxtakochi ticks collected in the state of são paulo (southeastern brazil). rickettsia was successfully isolated by the shell vial technique and established in vero cell culture from six ticks (six isolates). dna extracted from infected cells of these isolates was tested by pcr and dna sequencing, using genus-specific rickettsia primers targeting the genes glta, ht ... | 2007 | 17142361 |
| the natural hosts for larvae and nymphs of amblyomma neumanni and amblyomma parvum (acari: ixodidae). | based on the hypothesis that birds and rodents are important hosts for subadults of the neotropical amblyomma neumanni and amblyomma parvum ticks, a survey of these type of hosts was carried out from july 2004 to march 2006, in quilino (a. parvum) and dean funes (a. neumanni), córdoba province, argentina. additionally, monthly tick counts were performed on cattle and goats with occasional tick search in other domestic hosts. records of questing height of subadult ticks on vegetation were also ca ... | 2006 | 17006739 |
| ticks (acari: ixodida: argasidae, ixodidae) infesting humans in northwestern cordoba province, argentina. | ticks infesting humans were collected from september 2004 to august 2005 in northwestern córdoba in an area with a southern limit in the locality of dean funes (30 degrees 25's 64 degrees 20'w) and san josé de las salinas (30 degrees 00's 64 degrees 37'w) in the north. the collections consisted in ticks found attached on man obtained from three sources: 1) specimens fixed on two workers during two successive days per month of field work in the northern part of the area which belongs to western c ... | 2006 | 16871909 |
| the life cycle of amblyomma neumanni ribaga, 1902 (acari: ixodidae) in the laboratory. | a colony of amblyomma neumanni was started with engorged females collected from cattle in the province of salta (24 degrees 51's, 65 degrees 33'w), argentina. the larvae and nymphs were fed on rabbits and the adults on calves. the non-parasitic stages were maintained in darkness at 27 +/- 1 degrees c and 83-86% rh. the life cycle (pre-feeding period not tested) had a mean duration of 205.7 days. the mean time (days) for the different phases of the cycle were as follows: feeding of females 8.8, p ... | 1999 | 10356766 |
| seasonal variation of ticks (ixodidae) in bos taurus x bos indicus cattle under rotational grazing in forested and deforested habitats in northwestern argentina. | the seasonal occurrence of ticks infesting cattle was monitored in a bos taurus x bos indicus commercial herd fed on a combination of native grasses and annual pastures in northwestern argentina. the number of female ticks (boophilus and amblyomma) and the proportion of cattle infested with larvae and nymphs of amblyomma ticks were recorded from a sample of 15 cows in 24 visits at intervals of 21-50 days from 5 december 1986 to 24 november 1988. the cattle were maintained on native grasses in fo ... | 1994 | 7839563 |
| amblyomma ticks found on cattle in the northwest of argentina. preliminary report. | the phytogeographical and seasonal distributions of three species of amblyomma ticks found on cattle are presented. the material studied was collected during a four-year survey in the northwest of argentina. amblyomma neumanni shows predilection for the chaqueno serrano district although it was also found in ecotones (phytogeographical transition zones) of the adjacent western chaqueno district and the province of las yungas. amblyomma cajennense was found in the western chaqueno and chaqueno se ... | 1982 | 7081892 |