On 17 April 2018 dengue mosquito larvae were detected in a routine sentinel tyre trap set by the Commonwealth Department of Agriculture and Water Resources at the Royal Australian Naval Base HMAS Coonawarra in Darwin. In response to the detection all receptacles at the Naval Base facility and adjacent Larrakeyah Defence Precinct military residential areas were treated with residual insecticide and adult mosquito control (fogging) and residual barrier spraying was carried out. Enhanced exotic mosquito surveillance was established to monitor for exotic mosquitoes. There have been no further detections of Ae. aegypti at HMAS Coonawarra.