title: Molecular characterization and phylogenetic study of coxsackievirus A24v causing outbreaks of acute hemorrhagic conjunctivitis (AHC) in Brazil.
abstract: BACKGROUND
  Coxsackievirus A24 variant (CA24v) is the most prevalent viral pathogen associated with acute hemorrhagic conjunctivitis (AHC) outbreaks. Sixteen years after its first outbreak in Brazil, this agent reemerged in 2003 in Brazil, spread to nearly all states and caused outbreaks until 2005. In 2009, a new outbreak occurred in the northeast region of the country. In this study, we performed a viral isolation in cell culture and characterized clinical samples collected from patients presenting symptoms during the outbreak of 2005 in Vitória, Espírito Santo State (ES) and the outbreak of 2009 in Recife, Pernambuco State (PE). We also performed a phylogenetic analysis of worldwide strains and all meaningful Brazilian isolates since 2003.
  
  
  RESULTS
  Sterile cotton swabs were used to collect eye discharges, and all 210 clinical samples were used to inoculate cell cultures. Cytopathic effects in HEp-2 cells were seen in 58 of 180 (32%) samples from Vitória and 3 of 30 (10%) samples from Recife. Phylogenetic analysis based on a fragment of the VP1 and 3C gene revealed that the CA24v causing outbreaks in Brazil during the years 2003, 2004 and 2005 evolved from Asian isolates that had caused the South Korean outbreak of AHC during the summer of 2002. However, the 2009 outbreak of AHC in Pernambuco was originated from the reintroduction of a new CA24v strain that was circulating during 2007 in Asia, where CA24v outbreaks has been continuously reported since 1970.
  
  
  CONCLUSIONS
  This study is the first phylogenetic analysis of AHC outbreaks caused by CA24v in Brazil. The results showed that Asian strains of CA24v were responsible for the outbreaks since 1987 and were independently introduced to Brazil in 2003 and 2009. Phylogenetic analysis of complete VP1 gene is a useful tool for studying the epidemiology of enteroviruses associated with outbreaks.
authors.affiliation: Laboratório de Enterovírus, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Fernando Neto
authors.initials: FN
authors.lastname: Tavares
authors.forename: Renata de Mendonça
authors.initials: Rde M
authors.lastname: Campos
authors.forename: Fernanda Marcicano
authors.initials: FM
authors.lastname: Burlandy
authors.forename: Rachel
authors.initials: R
authors.lastname: Fontella
authors.forename: Maria Mabel Monte
authors.initials: MM
authors.lastname: de Melo
authors.forename: Eliane Veiga
authors.initials: EV
authors.lastname: da Costa
authors.forename: Edson Elias
authors.initials: EE
authors.lastname: da Silva
mesh_terms: D000086042:3C Viral Proteases; D001938:Brazil / Q000453:epidemiology; D036022:Capsid Proteins / Q000235:genetics; D045744:Cell Line, Tumor; D003232:Conjunctivitis, Acute Hemorrhagic / Q000453:epidemiology / Q000821:virology*; D003546:Cysteine Endopeptidases / Q000235:genetics; D004196:Disease Outbreaks; D030015:Enterovirus C, Human / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014764:Viral Proteins / Q000235:genetics
chemical_list: D036022:Capsid Proteins; D012367:RNA, Viral; D014764:Viral Proteins; D003546:Cysteine Endopeptidases; D000086042:3C Viral Proteases