Fig 1.
Map of Victoria, Australia, showing the 17 local government authorities that participated in adult mosquito surveillance for MVEV as part of the VADCP for the 2022–23 mosquito season.
Councils shaded in black with white borders indicate councils involved in mosquito surveillance for MVEV and JEV across north central and northern Victoria (including Mil – Mildura Rural City Council, SH – Swan Hill Rural City Council, Gan – Gannawarra Shire Council, Bul – Buloke Shire Council, NG – Northern Grampians Shire Council, Hor – Horsham Rural City Council, Lod – Loddon Shire Council, Cam – Campaspe Shire Council, GB – City of Greater Bendigo, Mac – Macedon Ranges Shire Council, Mit – Mitchell Shire Council, Str – Strathbogie Shire Council, GS – Greater Shepparton City Council, Moi – Moira Shire Council, Ind – Indigo Shire Council, Wod – City of Wodonga and Wan – Rural City of Wangaratta). Base maps are derived from the Australian Bureau of Statistics postal areas (POA) shapefile POA_2016_AUST, available here. The file has been modified to include Local Government Authority boundaries and is distributed under the Creative Commons Attribution 4.0 International, Accessed 21/03/2025.
Table 1.
A comparison of long-term mean monthly and annual rainfall (mm) collected over 25 years with the mean average monthly and annual rainfall (mm) recorded in 2022 alone, across six weather stations from the headwaters of the Murray River in the east to the mouth of the Murray River system in the west including Wodonga, Moira, Campaspe, Gannawarra, Swan Hill and Mildura. Meteorological data collected from the Bureau of Meteorology 2024, Government of Australia.
Fig 2.
Monthly rainfall (mm) recorded at six weather stations along the Murray River from July 2014 to June 2024 and the corresponding abundance of mosquitoes per trap per trap night each month.
Fig 2A) Eastern headwaters of the Murray River including Wodonga – Wodonga, Moira – Cobram Goulburn Murray, and Campaspe - Echuca Aerodrome weather stations; Fig 2B) western section of the Murray River including Gannawarra - Kerang Model Farm, Swan Hill – Swan Hill Aerodrome and Mildura - Mildura Airport weather stations. Meteorological data collected from the Bureau of Meteorology 2024, Government of Australia.
Fig 3.
Satellite imagery of the derived flood extent (red) generated by automated and manual processing of data at a given point in time for October 2022 (may not represent the maximum flood extent).
Emergency Management Victoria, State Government Victoria. The file has been modified to include Local Government Authority boundaries and is distributed under the Creative Commons Attribution 4.0 International, Accessed 21/03/2025. Available at: Victorian Flood History October 2022 Event Public - Dataset - Victorian Government Data Directory.
Table 2.
A comparison of long-term average monthly and annual maximum temperatures (0C) collected over 28 years with the mean average monthly and annual maximum temperatures (0C) recorded in 2022 alone, across six weather stations from the headwaters of the Murray River in the east to the mouth of the Murray River system in the west including Wodonga, Moira, Campaspe, Gannawarra, Swan Hill and Mildura. Meteorological data collected from the Bureau of Meteorology 2024, Government of Australia.
Table 3.
A comparison of long-term average monthly and annual minimum temperatures (0C) collected over 28 years with the mean average monthly and annual minimum temperatures (0C) recorded in 2022 alone, across six weather stations from the headwaters of the Murray River in the east to the mouth of the Murray River system in the west including Wodonga, Moira, Campaspe, Gannawarra, Swan Hill and Mildura. Meteorological data collected from the Bureau of Meteorology 2024, Government of Australia.
Fig 4.
Mosquito species abundance and composition per trapping week collected from EVS CO2 light traps deployed across 17 north-central and northern LGAs during the 2022–23 mosquito season.
Fig 4A) describes the average mosquito species abundance per trap per trap night and Fig 4B) represents the percentage composition of mosquito species per trap per trap night. Where coloured mosquito species indicate confirmed or implicated vectors of MVEV, greyed species indicate mosquitoes currently unknown to transmit MVEV and the blue arrow indicates the timing of rainfall events that led to flooding across the region.
Table 4.
Breakdown of mosquito composition associated with the testing of 102 pools from the 48 MVEV positive traps collected throughout the 2022–23 mosquito season across Victoria.
Table 5.
The number of mosquitoes tested in species specific pools, the number of positive detections compared to the total number of pools tested, the maximum Likelihood Estimate (based on presence/absence of MVEV detections in species specific mosquito pools, based on uneven pool sizes) and 95% confidence Intervals for species specific pools of Cx annulirostris and Cx australicus during the 2022-23 mosquito season.
Fig 5.
Prevalence of Culex australicus (orange), Culex annulirostris (red), Aedes sagax (yellow), Culex quinquefasciatus (dark blue), not speciated mosquitoes (grey) and the number of positive pools of MVEV (black bars) detected from mosquitoes throughout the 2022–23 season.
Fig 6.
Distribution of mosquito surveillance traps across Victoria from the 17 LGAs conducting surveillance in high risk MVEV areas during the 2022–23 season - grey markers indicate traps without detection of MVEV; black circles indicate trap locations with positive detections of MVEV; red numbers indicate the number of detections at each trap site.
Base maps are derived from the Australian Bureau of Statistics postal areas (POA) shapefile POA_2016_AUST, available here. The file has been modified to include Local Government Authority boundaries and mosquito trap locations distributed under the Creative Commons Attribution 4.0 International, Accessed 21/03/2025.