The epidemiology of imported and locally acquired dengue in Australia, 2012-2022

Asma Sohail; Katherine L Anders; Sarah L McGuinness; Karin Leder

doi:10.1093/jtm/taae014

The epidemiology of imported and locally acquired dengue in Australia, 2012-2022

J Travel Med. 2024 Mar 1;31(2):taae014. doi: 10.1093/jtm/taae014.

Authors

Asma Sohail^{1

2}, Katherine L Anders^{1

3}, Sarah L McGuinness^{1

4}, Karin Leder^{1

5}

Affiliations

¹ School of Public Health and Preventive Medicine, Monash University, 553 St Kilda Road, Melbourne, Victoria 3004, Australia.
² Infectious Diseases Department, Grampians Health Service, 1 Drummond Street North, Ballarat, Victoria 3350, Australia.
³ World Mosquito Program, Monash University, 12 Innovation Walk, Clayton, Victoria 3800, Australia.
⁴ Infectious Diseases Department, Alfred Health, 55 Commercial Road, Melbourne, Victoria 3004, Australia.
⁵ Victorian Infectious Diseases Service, Melbourne Health, 300 Grattan Street, Parkville, Victoria 3050, Australia.

Abstract

Background: Dengue is the most important arboviral disease globally and poses ongoing challenges for control including in non-endemic countries with competent mosquito vectors at risk of local transmission through imported cases. We examined recent epidemiological trends in imported and locally acquired dengue in Australia, where the Wolbachia mosquito population replacement method was implemented throughout dengue-prone areas of northern Queensland between 2011 and 2019.

Methods: We analysed dengue cases reported to the Australian National Notifiable Disease Surveillance System between January 2012 and December 2022, and Australian traveller movement data.

Results: Between 2012 and 2022, 13 343 dengue cases were reported in Australia (median 1466 annual cases); 12 568 cases (94.2%) were imported, 584 (4.4%) were locally acquired and 191 (1.4%) had no origin recorded. Locally acquired cases decreased from a peak in 2013 (n = 236) to zero in 2021-22. Annual incidence of imported dengue ranged from 8.29/100 000 (n = 917 cases) to 22.10/100 000 (n = 2203) annual traveller movements between 2012 and 2019, decreased in 2020 (6.74/100 000 traveller movements; n = 191) and 2021 (3.32/100 000 traveller movements; n = 10) during COVID-19-related border closures, then rose to 34.79/100 000 traveller movements (n = 504) in 2022. Imported cases were primarily acquired in Southeast Asia (n = 9323; 74%), Southern and Central Asia (n = 1555; 12%) and Oceania (n = 1341; 11%). Indonesia (n = 5778; 46%) and Thailand (n = 1483; 12%) were top acquisition countries. DENV-2 (n = 2147; 42%) and DENV-1 (n = 1526; 30%) were predominant serotypes.

Conclusion: Our analysis highlights Australia's successful control of locally acquired dengue with Wolbachia. Imported dengue trends reflect both Australian travel destinations and patterns and local epidemiology in endemic countries.

Keywords: Infectious disease; arbovirus; imported infection; notifiable disease; surveillance; travel.

MeSH terms

Animals
Arbovirus Infections* / epidemiology
Australia / epidemiology
Culicidae*
Dengue* / epidemiology
Humans
Queensland / epidemiology

Abstract

MeSH terms

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