Objectives: Melioidosis is an often fatal disease in humans and
animals and endemic in Southeast Asia and northern Australia. It is caused by
the environmental bacterium Burkholderia pseudomallei. We analysed weather and
climate factors preceding new melioidosis cases in Darwin and compared the time
between weather event and admission to hospital for severe and average wet
Methods: In a time-series analysis from 1990 to 2013 we applied a
boosted regression tree and a negative binomial model to investigate the
association between melioidosis cases and weather events. Fitted Fourier terms
controlled for long-term seasonal trends.
Results: We found a rise in the dew point, cloud cover,
rainfall, maximum temperature and groundwater to be associated with an
increased risk to acquire melioidosis. A shorter 'putative' incubation period
was evident after severe rainfall events. Rainfall occurring early in the wet
season was linked to more cases as was an increase in the local sea surface
temperature reflecting local weather dynamics and precipitation.
Conclusions: Our findings demonstrate a statistical association between frequency of recorded melioidosis cases and the nature and timing of rainfall related events and suggest a future rise in the sea surface and ambient temperature may lead to increased melioidosis.