title: Impacts of El Niño Southern Oscillation and Indian Ocean Dipole on dengue incidence in Bangladesh.
abstract: Dengue dynamics are driven by complex interactions between hosts, vectors and viruses that are influenced by environmental and climatic factors. Several studies examined the role of El Niño Southern Oscillation (ENSO) in dengue incidence. However, the role of Indian Ocean Dipole (IOD), a coupled ocean atmosphere phenomenon in the Indian Ocean, which controls the summer monsoon rainfall in the Indian region, remains unexplored. Here, we examined the effects of ENSO and IOD on dengue incidence in Bangladesh. According to the wavelet coherence analysis, there was a very weak association between ENSO, IOD and dengue incidence, but a highly significant coherence between dengue incidence and local climate variables (temperature and rainfall). However, a distributed lag nonlinear model (DLNM) revealed that the association between dengue incidence and ENSO or IOD were comparatively stronger after adjustment for local climate variables, seasonality and trend. The estimated effects were nonlinear for both ENSO and IOD with higher relative risks at higher ENSO and IOD. The weak association between ENSO, IOD and dengue incidence might be driven by the stronger effects of local climate variables such as temperature and rainfall. Further research is required to disentangle these effects.
authors.affiliation: School of Public Health and Social Work, Queensland University of Technology, Brisbane, QLD 4059, Australia.
authors.forename: Shahera
authors.initials: S
authors.lastname: Banu
authors.affiliation: School of Population Health, University of Queensland, Brisbane, QLD 4006, Australia.
authors.forename: Yuming
authors.initials: Y
authors.lastname: Guo
authors.affiliation: School of Public Health and Social Work, Queensland University of Technology, Brisbane, QLD 4059, Australia.
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Hu
authors.affiliation: Environmental Futures Research Institute, Griffith School of Environment, Griffith University, Brisbane, QLD 4111, Australia.
authors.forename: Pat
authors.initials: P
authors.lastname: Dale
authors.affiliation: Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia.
authors.forename: John S
authors.initials: JS
authors.lastname: Mackenzie
authors.affiliation: School of Mathematical Sciences and Institute for Future Environments, Queensland University of Technology, Brisbane, QLD 4059, Australia.
authors.forename: Kerrie
authors.initials: K
authors.lastname: Mengersen
authors.affiliation: School of Public Health and Social Work, Queensland University of Technology, Brisbane, QLD 4059, Australia.
authors.forename: Shilu
authors.initials: S
authors.lastname: Tong
mesh_terms: D001459:Bangladesh / Q000453:epidemiology; D003715:Dengue / Q000453:epidemiology* / Q000209:etiology*; D059000:El Nino-Southern Oscillation; D006801:Humans; D015994:Incidence; D019156:Indian Ocean; D012621:Seasons; D013696:Temperature