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

Abstract

BackgroundRabies 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.MethodsWe 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.ResultsBased 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.ConclusionsThis 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.

Rabia en Potos flavus identificados en el departamento de Madre de Dios, Perú

“…Por otro lado, existe evidencia acerca del papel como vector de rabia silvestre de los murciélagos no hematófagos (17)(18)(19) . De los murciélagos no hematófagos analizados como parte de la vigilancia en algunos países, la proporción de murciélagos con anticuerpos contra el virus de la rabia varía de 3,1 a 5,4% en Argentina (17) ; 6,7% en los Estados Unidos (20) y 1% en Brasil (21) .…”

“…De los murciélagos no hematófagos analizados como parte de la vigilancia en algunos países, la proporción de murciélagos con anticuerpos contra el virus de la rabia varía de 3,1 a 5,4% en Argentina (17) ; 6,7% en los Estados Unidos (20) y 1% en Brasil (21) . En la presente serie no pudimos determinar la forma de exposición al virus o comprobar historia o evidencia de mordeduras en las "chosnas".…”

Monoclonal antibodies for characterization of rabies virus isolated from non-hematophagous bats in Brazil

“…However, antigenic analysis is unable to identify RABV isolates obtained from several reservoirs species because these isolates produced atypical reaction patterns or incompatible profiles. [17][18][19][20][21][22]42]. The genetic analysis of the viral nucleoprotein sequence allowed further characterization of those isolates.…”

Ecology and Geography of Transmission of Two Bat-Borne Rabies Lineages in Chile

“…RABV lineages generally show specificity to particular bat hosts [9]–[11]. Antigenic typing depends on use of monoclonal antibodies; their power depends on numbers of monoclonal antibodies that bind consistently to antigenic sites that are conserved in a viral strain [8], [12].…”

“…Lasiurus cinereus differs, carrying AgV6 across its entire geographic distribution [15]. Viral specificity to these two host species has been confirmed with molecular analyses [9], [10], [13]. These bat species presently constitute the principal rabies reservoirs in Chile [16], [17], but little is known about roles of different hosts in their ecology and distribution.…”