title: Genetic divergence and dispersal of yellow fever virus, Brazil.
abstract: An analysis of 79 yellow fever virus (YFV) isolates collected from 1935 to 2001 in Brazil showed a single genotype (South America I) circulating in the country, with the exception of a single strain from Rondonia, which represented South America genotype II. Brazilian YFV strains have diverged into two clades; an older clade appears to have become extinct and another has become the dominant lineage in recent years. Pairwise nucleotide diversity between strains ranged from 0% to 7.4%, while amino acid divergence ranged from 0% to 4.6%. Phylogenetic analysis indicated traffic of virus variants through large geographic areas and suggested that migration of infected people may be an important mechanism of virus dispersal. Isolation of vaccine virus from a patient with a fatal case suggests that vaccine-related illness may have been misdiagnosed in the past.
authors.affiliation: World Health Organization Collaborating Center for Arbovirus Reference and Research, Instituto Evandro Chagas, Belém, Brazil. pedrovasconcelos@iec.pa.gov.br
authors.forename: Pedro F C
authors.initials: PF
authors.lastname: Vasconcelos
authors.forename: Juliet E
authors.initials: JE
authors.lastname: Bryant
authors.forename: Travassos P A
authors.initials: TP
authors.lastname: da Rosa
authors.forename: Robert B
authors.initials: RB
authors.lastname: Tesh
authors.forename: Sueli G
authors.initials: SG
authors.lastname: Rodrigues
authors.forename: Alan D T
authors.initials: AD
authors.lastname: Barrett
mesh_terms: D000595:Amino Acid Sequence; D001938:Brazil / Q000453:epidemiology; D019143:Evolution, Molecular; D014644:Genetic Variation; D006801:Humans; D017720:Molecular Epidemiology; D010802:Phylogeny; D016415:Sequence Alignment; D015004:Yellow Fever / Q000453:epidemiology / Q000821:virology; D015005:Yellow fever virus / Q000235:genetics*