A novel terrestrial rabies virus lineage occurring in south america: Origin, diversification, and evidence of contact between wild and domestic cycles

The rabies virus (RABV) is characterized by a history dominated by host shifts within and among bats and carnivores. One of the main outcomes of long-term RABV maintenance in dogs was the establishment of variants in a wide variety of mesocarnivores. In this study, we present the most comprehensive phylogenetic and phylogeographic analysis, contributing to a better understanding of the origins, diversification, and the role of different host species in the evolution and diffusion of a dog-related variant endemic of South America. A total of 237 complete Nucleoprotein gene sequences were studied, corresponding to wild and domestic species, performing selection analyses, ancestral states reconstructions, and recombination analyses. This variant originated in Brazil and disseminated through Argentina and Paraguay, where a previously unknown lineage was found. A single host shift was identified in the phylogeny, from dog to the crab-eating fox (Cerdocyon thous) in the Northeast of Brazil. Although this process occurred in a background of purifying selection, there is evidence of adaptive evolution-or selection of sub-consensus sequences-in internal branches after the host shift. The interaction of domestic and wild cycles persisted after host switching, as revealed by spillover and putative recombination events.Fil: Caraballo, Diego Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Lema, Cristina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio E Instituto de Salud "Dr. C. G. Malbran". Departamento Virus; ArgentinaFil: Novaro, Laura. Ministerio de Agricultura, Ganadería, Pesca y Alimento. Servicio Nacional de Sanidad y Calidad Agroalimentaria; ArgentinaFil: Gury Dohmen, Federico. Gobierno de la Ciudad Autónoma de Buenos Aires. Ministerio de Salud. Instituto de Zoonosis Luis Pasteur; ArgentinaFil: Russo, Susana. Ministerio de Agricultura, Ganadería, Pesca y Alimento. Servicio Nacional de Sanidad y Calidad Agroalimentaria; ArgentinaFil: Beltrán, Fernando J.. Gobierno de la Ciudad Autónoma de Buenos Aires. Ministerio de Salud. Instituto de Zoonosis Luis Pasteur; ArgentinaFil: Palacios, Gustavo. Icahn School of Medicine at Mount Sinai; Estados UnidosFil: Cisterna, Daniel Marcelo. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio E Instituto de Salud "Dr. C. G. Malbran". Departamento Virus; Argentin

“Candidatus Rickettsia andeanae” en Amblyomma tigrinum, San Luis, Argentina

El objetivo del estudio fue detectar especies del género Rickettsia en garrapatas de la especie Amblyomma tigrinum colectadas sobre carnívoros domésticos y en sangre de caninos domésticos de la provincia de San Luis (Argentina). Entre 2013 y 2015 se colectaron 56 garrapatas adultas de la especie A. tigrinum sobre caninos y felinos domésticos, y se obtuvieron 65 muestras sanguíneas de caninos. Tres garrapatas resultaron positivas mediante la amplificación de un fragmento del espacio intergénico 23S-5S ARNr del género Rickettsia, lográndose secuenciar uno de los productos positivos. La muestra positiva secuenciada también resultó positiva por PCRs de los fragmentos de los genes gltA y ompA. Las secuencias obtenidas resultaron tener una identidad del 100 % de identidad con “Candidatus Rickettsia andeanae”. Todas las muestras sanguíneas resultaron negativas. “Ca. R. andeanae” no ha sido asociada con enfermedad en humanos o animales, sin embargo, es necesario realizar nuevas investigaciones para lograr un mayor conocimiento del riesgo potencial de transmisión de rickettsiosis en la región. SUMMARY. “Candidatus Rickettsia andeanae” in Amblyomma tigrinum ticks from San Luis (Argentina). The aim of this study was to detect species of Rickettsia in Amblyomma tigrinum ticks collected from domestic carnivores and blood of domestic dogs of San Luis (Argentina). Between 2013 and 2015, 56 adults of A. tigrinum from dogs and cats and 65 blood from dogs were collected. Three ticks were positive by amplification of a 23S-5S rRNA fragment, and the sequence of one of the positive products was obtained. The positive sample sequenced was positive by PCRs of fragments of genes gltA and ompA. The sequences obtained were 100% identical with "Candidatus Rickettsia andeanae". All blood samples were negative. “Ca. R. andeanae” has not been associated with disease in humans or animals; however, further research is necessary to achieve greater awareness of the potential risk of transmission of rickettsial diseases in the region

High diversity of rabies viruses associated with insectivorous bats in Argentina: presence of several independent enzootics

BACKGROUND Rabies is a fatal infection of the central nervous system primarily transmitted by rabid animal bites. Rabies virus (RABV) circulates through two different epidemiological cycles: terrestrial and aerial, where dogs, foxes or skunks and bats, respectively, act as the most relevant reservoirs and/or vectors. It is widely accepted that insectivorous bats are not important vectors of RABV in Argentina despite the great diversity of bat species and the extensive Argentinean territory. METHODS We studied the positivity rate of RABV detection in different areas of the country, and the antigenic and genetic diversity of 99 rabies virus (RABV) strains obtained from 14 species of insectivorous bats collected in Argentina between 1991 and 2008. RESULTS Based on the analysis of bats received for RABV analysis by the National Rabies system of surveillance, the positivity rate of RABV in insectivorous bats ranged from 3.1 to 5.4%, depending on the geographic location. The findings were distributed among an extensive area of the Argentinean territory. The 99 strains of insectivorous bat-related sequences were divided into six distinct lineages associated with Tadarida brasiliensis, Myotis spp, Eptesicus spp, Histiotus montanus, Lasiurus blosseviilli and Lasiurus cinereus. Comparison with RABV sequences obtained from insectivorous bats of the Americas revealed co-circulation of similar genetic variants in several countries. Finally, inter-species transmission, mostly related with Lasiurus species, was demonstrated in 11.8% of the samples. CONCLUSIONS This study demonstrates the presence of several independent enzootics of rabies in insectivorous bats of Argentina. This information is relevant to identify potential areas at risk for human and animal infection.Fil: Piñero, Carolina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirosis; Argentina.Fil: Gury Dohmen, Federico. Instituto de Zoonosis Dr. Luis Pasteur; Argentina.Fil: Beltran, Fernando. Instituto de Zoonosis Dr. Luis Pasteur; Argentina.Fil: Martinez, Leila. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirosis; Argentina.Fil: Novaro, Laura. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorio y Control Técnico; Argentina.Fil: Russo, Susana. Servicio Nacional de Sanidad y Calidad Agroalimentaria. Dirección de Laboratorio y Control Técnico; Argentina.Fil: Palacios, Gustavo. George Mason University. National Center for Biodefense and Infectious Diseases; Estados Unidos.Fil: Cisterna, Daniel. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Servicio de Neurovirosis; Argentina

High Diversity of Rabies Viruses Associated with Insectivorous Bats in Argentina: Presence of Several Independent Enzootics

<div><h3>Background</h3><p>Rabies is a fatal infection of the central nervous system primarily transmitted by rabid animal bites. Rabies virus (RABV) circulates through two different epidemiological cycles: terrestrial and aerial, where dogs, foxes or skunks and bats, respectively, act as the most relevant reservoirs and/or vectors. It is widely accepted that insectivorous bats are not important vectors of RABV in Argentina despite the great diversity of bat species and the extensive Argentinean territory.</p> <h3>Methods</h3><p>We studied the positivity rate of RABV detection in different areas of the country, and the antigenic and genetic diversity of 99 rabies virus (RABV) strains obtained from 14 species of insectivorous bats collected in Argentina between 1991 and 2008.</p> <h3>Results</h3><p>Based on the analysis of bats received for RABV analysis by the National Rabies system of surveillance, the positivity rate of RABV in insectivorous bats ranged from 3.1 to 5.4%, depending on the geographic location. The findings were distributed among an extensive area of the Argentinean territory. The 99 strains of insectivorous bat-related sequences were divided into six distinct lineages associated with <em>Tadarida brasiliensis</em>, <em>Myotis spp</em>, <em>Eptesicus spp</em>, <em>Histiotus montanus</em>, <em>Lasiurus blosseviilli</em> and <em>Lasiurus cinereus</em>. Comparison with RABV sequences obtained from insectivorous bats of the Americas revealed co-circulation of similar genetic variants in several countries. Finally, inter-species transmission, mostly related with <em>Lasiurus</em> species, was demonstrated in 11.8% of the samples.</p> <h3>Conclusions</h3><p>This study demonstrates the presence of several independent enzootics of rabies in insectivorous bats of Argentina. This information is relevant to identify potential areas at risk for human and animal infection.</p> </div

Geographic distribution of RABV sublineages associated with insectivorous bats from Argentina.

<p>Geographic distribution of RABV sublineages associated with insectivorous bats from Argentina.</p

Consensus amino acid sequences of bat rabies viruses from Argentina.

<p>The last 88 amino acids encoded by the rabies virus nucleoprotein gene at the carboxy terminus are shown.</p

Phylogenetic tree of insectivorous bats rabies from Americas.

<p>Tree was generated of N-J method (Kimura two-parameter model) of a portion of the N gene coding sequence (264 nt). Bold font indicates RABV samples from Argentinean bats analyzed in this study. The geographical origins of comparator group sequences are included in the name of each sample. Sample numbers appeared as GenBank database.</p