Risks for Ross River virus disease in tropical Australia.
BACKGROUND
There are no analytical studies of individual risks for Ross River virus (RRV) disease. Therefore, we set out to determine individual risk and protective factors for RRV disease in a high incidence area and to assess the utility of the case-control design applied for this purpose to an arbovirus disease.


METHODS
We used a prospective matched case-control study of new community cases of RRV disease in the local government areas of Cairns, Mareeba, Douglas, and Atherton, in tropical Queensland, from January 1 to May 31, 1998.


RESULTS
Protective measures against mosquitoes reduced the risk for disease. Mosquito coils, repellents, and citronella candles each decreased risk by at least 2-fold, with a dose-response for the number of protective measures used. Light-coloured clothing decreased risk 3-fold. Camping increased the risk 8-fold.


CONCLUSIONS
These risks were substantial and statistically significant, and provide a basis for educational programs on individual protection against RRV disease in Australia. Our study demonstrates the utility of the case-control method for investigating arbovirus risks. Such a risk analysis has not been done before for RRV infection, and is infrequently reported for other arbovirus infections.
Harley
David
D
Queensland Centre for Intellectual and Developmental Disability, School of Population Health, University of Queensland, Mater Hospital, Brisbane, 4101, Queensland, Australia. D.Harley@uq.edu.au
Ritchie
Scott
S
Bain
Chris
C
Sleigh
Adrian C
AC
D000293:Adolescent; D000328:Adult; D000368:Aged; D018354:Alphavirus Infections / Q000453:epidemiology* / Q000517:prevention & control; D000818:Animals; D002165:Camping; D016022:Case-Control Studies; D003020:Clothing; D004197:Disease Reservoirs; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011793:Queensland / Q000453:epidemiology; D012307:Risk Factors; D012398:Ross River virus; D014329:Tropical Climate