title: El Niño-Southern Oscillation, local weather and occurrences of dengue virus serotypes.
abstract: Severe dengue fever is usually associated with secondary infection by a dengue virus (DENV) serotype (1 to 4) that is different to the serotype of the primary infection. Dengue outbreaks only occur following importations of DENV in Cairns, Australia. However, the majority of imported cases do not result in autochthonous transmission in Cairns. Although DENV transmission is strongly associated with the El Niño-Southern Oscillation (ENSO) climate cycle and local weather conditions, the frequency and potential risk factors of infections with the different DENV serotypes, including whether or not they differ, is unknown. This study used a classification tree model to identify the hierarchical interactions between Southern Oscillation Index (SOI), local weather factors, the presence of imported serotypes and the occurrence of the four autochthonous DENV serotypes from January 2000-December 2009 in Cairns. We found that the 12-week moving average of SOI and the 2-week moving average of maximum temperature were the most important factors influencing the variation in the weekly occurrence of the four DENV serotypes, the likelihoods of the occurrence of the four DENV serotypes may be unequal under the same environmental conditions, and occurrence may be influenced by changes in global and local environmental conditions in Cairns.
authors.affiliation: School of Public Health and Social Work, Institute of Health and Biomedecal Innovation, Queensland University of Technology, Brisbane, Queensland, Australia.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Huang
authors.affiliation: Research School of Population Health, The Australian National University, Canberra, ACT, Australia.
authors.forename: Archie C A
authors.initials: AC
authors.lastname: Clements
authors.affiliation: School of Public Health, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Gail
authors.initials: G
authors.lastname: Williams
authors.affiliation: Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.
authors.forename: Gregor
authors.initials: G
authors.lastname: Devine
authors.affiliation: School of Public Health and Social Work, Institute of Health and Biomedecal Innovation, Queensland University of Technology, Brisbane, Queensland, Australia.
authors.forename: Shilu
authors.initials: S
authors.lastname: Tong
authors.affiliation: School of Public Health and Social Work, Institute of Health and Biomedecal Innovation, Queensland University of Technology, Brisbane, Queensland, Australia.
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Hu
mesh_terms: D003716:Dengue Virus / Q000145:classification*; D059000:El Nino-Southern Oscillation; D006801:Humans; D011793:Queensland; D065288:Serogroup; D013997:Time Factors; D014887:Weather