A time series of infectious-like events in Australia between 2000 and 2013 leading to extended periods of increased deaths (all-cause mortality) with possible links to increased hospital medical admissions

Background and aims: Trends in deaths and medical admissions in the UK and Europe show evidence for a series of infectious-like events. These events have been overlooked by traditional surveillance methodologies. Preliminary evidence points to a rise in medical admissions in Australia around the same time as those observed in Europe, and this study was aimed to evaluate whether the deaths are occurred in similar way. Methods: Both monthly and annually deaths in the states of Australia and smaller local authority geographies were analyzed for evidence of large and abrupt step-like increases which endured for a minimum of 12 months. Monthly data were analyzed using a 12-month running total of deaths, while annual data compared one year to the next by converting changes in deaths into standard deviation equivalents in an assumed Poisson distribution. Results: At State and Local government level, there was evidence for spatial spread of an agent causing step-like changes in deaths which endured for 12 to 18 months before returning to the expected time-trajectory for deaths. The maximum step-like change ranged from 4.1% in New South Wales to 11.7% in the Northern Territory. The magnitude of the step-change was reduced with the size of the spatial geography and followed a power law function with size. Conclusion: The same events leading to increased deaths and medical admissions in the UK and Europe (Northern Hemisphere), also appeared to be operating in Australia (Southern Hemisphere) at roughly the same points in time. A common infectious source appeared to be implicated.