Proffered Papers Australian Society for Microbiology Annual Scientific Meeting 2016

Monitoring of DENV-2 in a Western Australian traveller cohort shows persistence of a novel Cosmopolitan genotype lineage that emerged in Indonesia in 2011 (#26)

Timo Ernst 1 , Suzi McCarthy 1 2 , Edward C Holmes 3 , David Smith 1 2 , Allison Imrie 1 2
  1. School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, WA, Australia
  2. PathWest Laboratory Medicine WA, Perth, WA
  3. Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney, Sydney, NSW

Dengue fever and severe dengue are caused by infection with any of the four dengue virus (DENV) serotypes, mosquito-borne RNA viruses in the Flavivirus genus. DENV circulate throughout the tropics and over 70% of the global disease burden is borne by those living in Southeast Asia and the Western Pacific region1. We have sequenced the E gene of DENV-2 isolated from returning travellers entering Western Australia between 2011 and 2015, most of whom had visited Indonesia. A phylogenetic tree was estimated using the maximum likelihood method.  We previously identified a novel lineage of DENV-2 Cosmopolitan genotype circulating in Indonesia2; the current study has found that this lineage has persisted in Indonesia into 2015. A second lineage within the Cosmopolitan genotype that is most closely related to strains from Nepal, Malaysia and Singapore emerged in 2014 in Bali and continues to persist into 2015. Furthermore, other co-circulating lineages of DENV-2 were also identified in viruses isolated from returning travellers, most of which are shown to be closely related to lineages known to have been circulating in Indonesia for some time. The distribution and prevalence of the DENV-2 lineages should continue to be monitored. Using returning travellers as sentinels can provide a timely method for identifying circulating DENV genotype data and can reveal epidemiological and evolutionary trends.

  1. 1) World Health Organization Western Pacific Region (2014) Dengue fact sheet. Available at http://www.wpro.who.int/mediacentre/factsheets/fs_09032012_Dengue/en/. Accessed 30 March 2016.
  2. 2) Ernst, T., McCarthy, S., Chidlow, G., Luang-Suarkia, D., Holmes, E. C., Smith, D. W., Imrie, A. (2015) Emergence of a New Lineage of Dengue Virus Type 2 Identified in Travelers Entering Western Australia from Indonesia, 2010-2012. PLoS Negl Trop Dis 9(1):e0003442.