Sources of Dengue Viruses Imported into Queensland, Australia, 2002–2010

摘要

To assess risk for importation of dengue virus (DENV) into Queensland, Australia, and sources of imported viruses, we sequenced the envelope region of DENV isolates from symptomatic patients with a history of travel during 2002–2010. The number of imported dengue cases greatly increased over the surveillance period, some of which were associated with domestic outbreaks. Patients reported traveling to (in order) Asia, Papua New Guinea, Pacifi c Island countries, and non–Asia-Pacifi c countries. By using phylogenetic methods, we assigned DENV isolates from returning residents and overseas visitors with viremia to a specifi c genotypic group. Genotypes circulating in Asia were extremely diverse. Genotyping and molecular clock analysis supported Asian origination of a strain that caused an outbreak of DENV-4 in Pacifi c Island countries during 2007–2009, and subsequently, in Innisfail, Australia, in 2009. Our fi ndings indicate that Asia is a major source of DENVs that are imported into Australia, causing a risk for epidemics