Melioidosis epidemiology and risk factors from a prospective whole-population study in northern Australia.
OBJECTIVE
The aims of this study were to describe the epidemiology of melioidosis in tropical northern Australia and to assess the importance of defined risk factors.


METHODS
The data were taken from a 14-year prospective study of 364 cases of melioidosis in the 'Top End' of the Northern Territory. A whole-population logistic regression model was used to estimate the crude and adjusted relative risk (RR) for the defined risk factors.


RESULTS
The mean age of the study population was 46.8 years, 264 (72.5%) were male, 178 (49%) were aboriginal Australians and 59 (16.2%) died from melioidosis. Average annual incidence was 19.6 cases per 100 000 population, with an estimated rate of 260 cases per 100,000 diabetics per year. Using a whole-population logistic regression model, the estimated crude and adjusted RR [95% confidence intervals (CI)] for melioidosis were 6.3 (5.1-7.8) and 4.0 (3.2-5.1) for those aged > or = 45 years, 2.3 (1.8-2.9) and 2.4 (1.9-3.0) for males, 2.9 (2.3-3.5) and 3.0 (2.3-4.0) for aboriginal Australians, 21.2 (17.1-26.3) and 13.1 (9.4-18.1) for diabetics, 2.7 (2.2-3.4) and 2.1 (1.6-2.6) for those with excess alcohol consumption, 6.8 (5.4-8.6) and 4.3 (3.4-5.5) for chronic lung disease and 6.7 (4.7-9.6) and 3.2 (2.2-4.8) for chronic renal disease, respectively.


CONCLUSIONS
Diabetes, excess alcohol intake, chronic renal disease and chronic lung disease are each independent risk factors for melioidosis. In tropical northern Australia, male sex, aboriginal ethnicity and age of > or = 45 years are also independent predictors for melioidosis. Impaired polymorph function may be critical in the predisposition to melioidosis.
Currie
Bart J
BJ
Menzies School of Health Research, Charles Darwin University, Darwin, Australia. bart@menzies.edu.au
Jacups
Susan P
SP
Cheng
Allen C
AC
Fisher
Dale A
DA
Anstey
Nicholas M
NM
Huffam
Sarah E
SE
Krause
Vicki L
VL
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D015897:Comorbidity; D019353:Endemic Diseases; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008554:Melioidosis / Q000453:epidemiology* / Q000401:mortality; D008875:Middle Aged; D015876:Northern Territory / Q000453:epidemiology; D011159:Population Surveillance / Q000379:methods; D011446:Prospective Studies; D012307:Risk Factors; D014329:Tropical Climate