Phylogenetic characterization of hantaviruses from wild rodents and hantavirus pulmonary syndrome cases in the state of Parana (southern Brazil)

Abstract

Over 1100 cases of hantavirus pulmonary syndrome (HPS) have occurred in Brazil since 1993, but little is known about Brazilian hantaviruses, and many of their rodent hosts remain unknown. The Araucaria hantavirus (ARAUV) was described recently from HPS patients from Paraná , in southern Brazil, but its host could not be identified. In this study, rodents were captured from regions with high HPS prevalence to address this issue. ARAUV RNA was detected in three distantly related rodent species: Oligoryzomys nigripes, Oxymycterus judex and Akodon montensis. Furthermore, a specimen of A. montensis was infected with a Jaborá -like virus, implying that A. montensis can be infected by at least two different hantaviruses. The presence of the same hantavirus strain in three different rodent species and the co-circulation of two different strains in the same rodent species highlight the potential for genomic reassortment, which could have an impact on hantavirus transmission dynamics in nature and on human epidemiology.Hantaviruses belong to the genus Hantavirus in the family Bunyaviridae and are found throughout most of the world. Similar to other members of the family, hantaviruses are enveloped viruses with an RNA genome comprised of three negative-sense, single-stranded segments. The large (L) RNA segment encodes an RNA-dependent RNA polymerase, the medium (M) segment encodes two envelope glycoproteins -Gn and Gc -processed from one precursor, and the small (S) segment encodes the nucleocapsid protein (N) (Plyusnin et al., 1996).Hantaviruses use small mammals as vectors, and in the wild, most of the different hantaviruses have been found to associate predominantly with a specific rodent species that acts as the host in a given geographical region (Plyusnin & Morzunov, 2001). Although sporadic spillover between rodents species has been suggested (Childs et al., 1994;Delfraro et al., 2008;Sousa et al.,. 2008), conclusive evidence that the studied viruses can establish productive infections in more than one rodent host species is still missing.Hantaviruses are transmitted to humans mainly through the inhalation of contaminated aerosols of rodent excreta (Lednicky, 2003;Schmaljohn & Patterson, 2001), but human-to-human transmission has also been described (Padula et al., 1998). These viruses are associated with two clinical syndromes, haemorrhagic fever with renal syndrome, described in Europe and Asia with a mortality rate of 1-15 %, and hantavirus pulmonary syndrome (HPS), described in the Americas with a mortality rate ranging from 40 to 60 % (Lundkvist & Niklasson, 1994;Johnson et al., 1999).Despite the increasing incidence of HPS in Brazil (Elkhoury, 2005), little is known about the genetic diversity of its causative agents, Brazilian hantaviruses (Table 1), and identification of their rodent hosts remains incomplete. The south-western region of the state of Paraná (southern Brazil, 26u 079 S 51u 319 W) is one of the most heavily affected areas of Brazil, with a high number of HPS cases: 168 cases have been reported ...

Detection of the first incidence of Akodon paranaensis naturally infected with the Jabora virus strain (Hantavirus) in Brazil

“…Hantaviruses can co-circulate in the same locality and can be maintained side-by-side in different rodent species, as reported for Juquitiba and JABV related viruses and other Old World hantaviruses (Artois et al 2007, Chu et al 2009, Raboni et al 2009b, Razzauti et al 2009, Oliveira et al 2011. In this study, we have identified JABV, which is associated with A. montensis and Akodon paranaensis, two related and sympatric rodent species in Midwestern SC (Jabora, 27º09'S 51º47'W).…”

Hantavirus Infection Prevalence in Wild Rodents and Human Anti-Hantavirus Serological Profiles from Different Geographic Areas of South Brazil

“…The molecular tests were carried out using various sets of primers that have been described previously. 6,7,12 The PCR products were purified (High Pure PCR kit, Roche Inc., Mannheim, Germany) and both strands were sequenced by the commercial Macrogen facility (Seoul, Republic of Korea).…”

“…6,7 This region borders Paraguay and Argentina in the West and the states of Santa Catarina (South) and São Paulo (North). Its main economic activities are agriculture, reforestation, and ecotourism.…”

“…Over the last 7 years our group has monitored HPS cases reported in Paraná by performing genetic analyses to determine the viral genotypes associated with these cases and rodent trapping to identify the species involved in hantavirus transmission. Epidemiological studies have revealed substantial differences in antibody prevalence in humans and rodents among the various regions of South Brazil, indicating that some communities are experiencing high frequencies of virus exposures [7][8][9] Since 2008, a collaborative network involving our institute, the State Health Department of Paraná and the Laboratory of Biology and Parasitology of Wild Mammals Reservoirs in Fiocruz, Rio de Janeiro has been responsible for carrying out programmed collections of wild rodents in different ecosystems throughout the state of Paraná and for collecting sera from individuals living in these areas. The aims of this program are to determine the distribution of wild rodents, the prevalence of anti-hantavirus antibodies in rodents and humans, and to identify the virus genotypes circulating in the surveyed areas.…”

Pequenos mamíferos não-voadores do Planalto Atlântico de São Paulo: identificação, história natural e ameaças

“…Sua distribuição geográfica não é bem conhecida, mas existem registros para Rio de Janeiro (D'Andrea et al 2007), Paraná (Raboni et al 2009) e Santa Catarina (Hershkovitz 1994, Cherem et al 2004.…”