Geographical range of Rio Mamoré virus (family Bunyaviridae, genus Hantavirus) in association with the small-eared pygmy rice rat (Oligoryzomys microtis)

Abstract

Hantavirus HTN.007 was originally isolated from a small-eared pygmy rice rat (Oligoryzomys microtis) captured in northeastern Peru. The results of analyses of nucleotide and amino acid sequence data in this study indicated that HTN.007 is a strain of Rio Mamoré virus (RIOMV) which is enzootic in small-eared pygmy rice rat populations in Bolivia. As such, the results of this study extend our knowledge of the geographical range of RIOMV and support the notion that the small-eared pygmy rice rat is the principal host of RIOMV.

FIG. 1.

Map showing the five localities at which RIOMV-infected small-eared pygmy rice rats (Oligoryzomys microtis) were captured in previous studies: (1) Iquitos (3°45′S, 73°11′W), (2) Rio Madidi (12°34′S, 67°00′W), (3) Rio Beni (14°16′S, 67°32′W), (4) Rio Tijamuchi (14°56′S, 65°09′W), and (5) Mineros (17°5′S, 63°40′W). RIOMV strains HTN·007 and OM 556 were isolated from small-eared pygmy rice rats captured near Iquitos and Rio Beni, respectively. RIOMV, Rio Mamoré virus.

FIG. 2.

Phylogenetic relationships among hantaviruses based on Bayesian analyses of (2A) complete nucleocapsid protein gene sequences and (2B) complete glycoprotein precursor gene sequences. The scale bars indicate the expected number of substitutions per site. The black dots (•) at the nodes indicate clade probability values of >95.0%. The branch labels in (2A) and (2B) include (in the following order) viral species, virus strain, and country. ANDV, Andes virus; BAYV, Bayou virus; BCCV, Black Creek Canal virus; CADV, Caño Delgadito virus; CATV, Catacamas virus; CHOV, Choclo virus; DOBV, Dobrava-Belgrade virus; ELMCV, El Moro Canyon virus; HTNV, Hantaan virus; ISLAV, Isla Vista virus; KHAV, Khabarovsk virus; LANV, Laguna Negra virus; MAPV, Maporal virus; MULV, Muleshoe virus; NYV, New York virus; PHV, Prospect Hill virus; PUUV, Puumala virus; RIOMV, Rio Mamoré virus; RIOSV, Rio Segundo virus; SEOV, Seoul virus; SNV, Sin Nombre virus.

FIG. 3.

Phylogenetic relationships among rodents based on Bayesian analysis of cytochrome b gene sequences. The scale bar indicates the expected number of substitutions per site. The black dots (•) at the nodes indicate clade probability values of >95.0%. The branch labels include (in the following order) identification number of the voucher specimen, species, and country. Mi·min, Microryzomys minutus (forest small rice rat); N·min, Neacomys minutus (Jurua bristly mouse); Ol·and, Oligoryzomys andinus (Andean pygmy rice rat); Ol·cha, Oligoryzomys chacoensis (Chacoan pygmy rice rat); Ol·des, Oligoryzomys destructor (destructive pygmy rice rat); Ol·fla, Oligoryzomys flavescens (yellow pygmy rice rat); Ol·ful, Oligoryzomys fulvescens (fulvous pygmy rice rat); Ol·lon, Oligoryzomys longicaudatus (long-tailed pygmy rice rat); Ol·mic, O. microtis (small-eared pygmy rice rat); Ol·moo, Oligoryzomys moojeni (Moojen's pygmy rice rat); Ol·nig, Oligoryzomys nigripes (black-footed pygmy rice rat); Ol·sp, Oligoryzomys species (pygmy rice rats not identified to species level); Ol·veg, Oligoryzomys vegetus (sprightly pygmy rice rat); Or·bal, Oreoryzomys balneator (Peruvian rice rat).