Genotypes of respiratory syncytial virus group B identified in Uruguay Brief Report

Summary. Genotypes of Human respiratory syncytial virus (HRSV) of group B from Uruguay were assigned to strains isolated during 1999 and 2001 outbreaks and others formerly reported isolated in the period 1989–1996. The nucleotide sequences of the C-terminal portion of the G protein were compared to sequences representative of previously defined HRSV genotypes. Most Uruguayan strains clustered into five of the previously identified genotypes. Nine isolates clustered in two genotypes named URU1 and URU2 which were not described up to present. Two of the analyzed sequences isolated in 2001 have a six nucleotide duplication that is discussed in terms of HRSV variability. ∗ Human respiratory syncytial virus is the single most important cause of severe lower respiratory tract infections in infants and young children world-wide [6]; it became an important pathogen for the elderly and immunocompromised adults [8]. Human respiratory syncytial virus (HRSV) is classified within the family Paramyxoviridae, with a non segmented negative stranded RNA that encodes for eleven proteins. Two antigenic groups A and B, have been identified by their reactivity with panels of monoclonal antibodies [1, 18] which correlated with different genetic groups [7]. The highest genetic diversity reported for the G attachment protein occurs between and within both groups A and B [17, 24]. Genetic variability of HRSV G glycoproteins from isolates of both groups has been studied in great detail around the world, identifying several variants or lineages within each group, which have been assigned to different genotypes [15, 19, 20, 28, 29].