Increased container-breeding mosquito risk owing to drought-induced changes in water harvesting and storage in Brisbane, Australia.
BACKGROUND
Extended drought conditions in south-east Queensland during the early 2000s have resulted in a culture of water harvesting and legislated water restrictions. Aedes notoscriptus is a container-breeding mosquito vector of Ross River and Barmah Forest viruses.


METHODS
From 2008-2009, the larval habitats and seasonal abundance of domestic container-breeding mosquitoes were recorded from three suburbs of Brisbane. A knowledge, attitudes and practice questionnaire was administered to householders. A low-cost, desktop methodology was used to predict the proportion of shaded premises compared with front-of-property estimates.


RESULTS
We highlight changes in the frequency of container categories for A. notoscriptus as a response to human behavioural changes to drought. Garden accoutrements, discarded household items and water storage containers accounted for 66.2% (525/793) of positive containers and 77.5% (73 441/94 731) of all immature mosquitoes. Of all household premises surveyed, 52.6% (550/1046) contained rainwater tanks and 29.4% (308/1046) harvested water in other containers, contrasting with a previous 1995 survey where neither category was observed. Both Premise Condition Index and shade directly correlated with positive premises.


CONCLUSIONS
Human response to drought has resulted in new habitats for domestic container-breeding mosquitoes. This recent trend of prolific water storage is similar to earlier years (1904-1943) in Brisbane when Aedes aegypti was present and dengue epidemics occurred.
Mosquito Control Laboratory, QIMR Berghofer Institute of Medical Research, 300 Herston Road, Brisbane, QLD 4006, Australia.
Brendan J
BJ
Trewin
Brian H
BH
Kay
Jonathan M
JM
Darbro
Tim P
TP
Hurst
D000330:Aedes / Q000254:growth & development / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001947:Breeding / Q000706:statistics & numerical data*; D055864:Droughts; D017753:Ecosystem; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D011793:Queensland; D012307:Risk Factors; D012621:Seasons; D018881:Suburban Health / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D014867:Water; D014881:Water Supply / Q000032:analysis* / Q000706:statistics & numerical data
D014867:Water
Climate change; Larval habitat; Mosquito control; PCI; Water storage