Global Distribution of Rubella Virus Genotypes

Abstract

Phylogenetic analysis of a collection of 103 E1 gene sequences from rubella viruses isolated from 17 countries from 1961 to 2000 confirmed the existence of at least two genotypes. Rubella genotype I (RGI) isolates, predominant in Europe, Japan, and the Western Hemisphere, segregated into discrete subgenotypes; intercontinental subgenotypes present in the 1960s and 1970s were replaced by geographically restricted subgenotypes after ~1980. Recently, active subgenotypes include one in the United States and Latin America, one in China, and a third that apparently originated in Asia and spread to Europe and North America, starting in 1997, indicating the recent emergence of an intercontinental subgenotype. A virus that potentially arose as a recombinant between two RGI subgenotypes was discovered. Rubella genotype II (RGII) showed greater genetic diversity than did RGI and may actually consist of multiple genotypes. RGII viruses were limited to Asia and Europe; RGI viruses were also present in most of the countries where RGII viruses were isolated.

Sequence and Phylogenetic Analysis of Wild Type Rubella virus isolated in Iran

“…In this study, phylogenetic analysis and alignment of nucleotide sequences of the rubella virus E1 gene belonging to the reference strains and Iranian viruses wild type (MF) and Takahasi vaccine strain has been performed. The phylogenetic analysis showed that the Iran wild "MF" isolate was classified into genotype 2B (RG II) which is mostly introduced from Asia but is more distributed in the world in comparison with the other genotypes in clade 2 (2,4,12). The Iran MF wild RV was isolated in 1999.…”

“…Sequence (genotype) information is providing a valuable data to epidemiological information in determining (12). The eradication efforts of measles and rubella in Iran are in the way.…”

“…As part of the surveillance component of these efforts, an understanding of the worldwide molecular epidemiology of rubella virus, which is limited, is necessary. Molecular epidemiologic surveillance provides important information on: origin of the virus, virus strains circulating in the country, and, whether these strains have become endemic in the country (2,4,5,9,12,13). After mass vaccination for rubella infection in Iran, seroepidemiological studies have been performed (11,14,15), but there is no molecular data for specific characterization of virus particularly virus genotyping up to now (Fig.…”

Novel Replicon-Based Reporter Gene Assay for Detection of Rubella Virus in Clinical Specimens

“…In terms of rapidity of the replicon-based assay, although cells inoculated with clinical specimens were incubated for 6 to 7 days before transfection with RUBrep/GFP-⌬NotI transcripts to duplicate the virus isolation procedures used previously (11), we have found that cultures inoculated with clinical specimens can be transfected 2 days postinoculation with GFP expression detectable 1 day posttransfection, for a total assay time of 3 days (W.-P. Tzeng, preliminary observations). In addition to virus detection, we showed that the novel replicon-based assay described here is also useful for virus genotyping, which remains a necessary part of the surveillance component of vaccination programs to determine virus distribution and transmission patterns (8,11,22,23). The E1 gene has been used for all molecular epidemiology studies done on RUB thus far, although the region of the E1 gene used in these studies has not been standardized.…”

“…At 6 to 7 days postinoculation, the P0 culture fluid was removed, and the cells were transfected with RUBrep/GFP-⌬NotI transcripts and observed for GFP expression as described above. At 2 days posttransfection with RUBrep/GFP-⌬NotI transcripts, total RNA was extracted by using Tri-Reagent (Molecular Research Center), and the presence of RUB genomic RNA was assayed with a genome-specific RT-PCR assay that amplified nt 8652 to 9124 within the E1 gene (lacking in RUBrep/GFP-⌬NotI); these nucleotides represent the "molecular epidemiology window" previously shown to be optimal for genotypic strain determination (22). The assay used the oligonucleotide nucleotide primer 5Ј-TTTTTTTTTCTATACAGCAAC-3 [oligonucleotide(dT), followed by the complement of the 3Ј 12 nt of the RUB genome to prime RT with Superscript III reverse transcriptase (Invitrogen) and upstream primer 5Ј-GCTTCCCCACCGACACCGTG-3Ј (colinear with nt 8652 to 8671 of the RUB genome)] and downstream primer 5Ј-GAGTCCGCACTTGCGCGCC T-3Ј (complementary to nt 9105 to 9124 of the RUB genome) for PCR.…”