Bacteria of the genera Ehrlichia and Rickettsia in ticks of the family Ixodidae with medical importance in Argentina

Abstract

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 infection with Ehrlichia spp. and Rickettsia spp. by PCR assays. Rickettsial DNA was detected in all tested tick species, with the exception of A. tonelliae. 'Candidatus Rickettsia amblyommii', 'Candidatus Rickettsia andeanae', and Rickettsia parkeri were found in A. neumanni, A. parvum, and A. triste, respectively. Another rickettsial species, Rickettsia bellii, was found in A. sculptum, A. ovale and H. juxtakochi. None of the tested ticks showed infection with Ehrlichia. The results of the study demonstrate that Rickettsia species belonging to the spotted fever group are associated with various species of Amblyomma throughout a wide area of northern Argentina, where cases of Amblyomma ticks biting humans are common.

Seasonal dynamics, geographical range size, hosts, genetic diversity and phylogeography of Amblyomma sculptum in Argentina

“…The first is associated to propagation of ticks in a new territory through movement of domestic animals. At the site where A. sculptum was collected, water buffalos were introduced more than ten years ago from the Formosa province, where A. sculptum is established (Ivancovich and Luciani, 1992;Sebastian et al, 2017;this work). It is possible that water buffalos translocated from Formosa have carried ticks to Corrientes Province, and A. sculptum has found a new system that is ecologically suitable for its development.…”

Molecular Detection of Candidatus Rickettsia andeanae and Ehrlichia sp. in Amblyomma pseudoconcolor Aragão, 1908 (Acari: Ixodidae) from the Argentinian Patagonia

“…Interestingly, the PCR assay amplifying the ompA gene that is specific for SFGR resulted negative in this study. However, previous studies have shown [ 24 , 25 ] that the applied PCR assay in this study is not appropriate for the detection of the ompA gene of Ca. R. andeanae and therefore must be replaced by another assay described by Ermeeva et al [ 26 ] in future studies.…”

“…R. andeanae in A. maculatum from Peru. Further, this rickettsial agent could be detected in A. parvum from Argentina and Brazil [ 24 , 25 , 28 ] and A. tigrinum from Argentina and Chile [ 29 , 30 ]. DNA of Ca .…”

Eco-epidemiología de los ectoparásitos de roedores silvestres (Cricetidae) y sinantrópicos (Muridae) en la provincia de Buenos Aires

“…En Sudamérica, la enfermedad rickettsial mayormente distribuida es la Fiebre de las Montañas Rocosas, una enfermedad mortal cuando no se instaura un tratamiento antibiótico adecuado (Labruna et al, 2011). Esta infección es provocada por Rickettsia rickettsii la cual es transmitida por la picadura de garrapatas del complejo Amblyomma cajennense, Amblyomma aureolatum y Rhipicephalus sanguineus sensu lato (Guedes et al, 2005;Labruna et al, 2011Labruna et al, , 2014Venzal & Nava, 2011;Venzal, 2013;Parola et al, 2013;Nava et al, 2017). En Argentina, las Fiebres Manchadas se encuentran distribuidas principalmente en dos regiones con cuadros clínicos diferenciados: el norte del país, donde Rickettsia rickettsii ocasiona la Fiebre Manchada, transmitida por especies de garrapatas del complejo…”