Estimating incidence of sexually transmissible infections in Australia

Ewan Cameron, Chris C. Drovandi, Jannah Baker, Wei Xian Lim, James Urquhart, Laith Yakob, James M. McCaw


The reported numbers of notifiable sexually transmitted infections in Australia are subject to a myriad of biases and limitations, including demographic, clinical, behavioural, and temporal factors. As such, trends in reported diagnosis rates may not reflect trends in true underlying incidence, thereby confounding any direct interpretation of raw notification data for public health research. The development of new methods to determine the true incidence and prevalence of an infection is a critical step for furthering the understanding of disease in the population. Here we devise a statistical model for chlamydia testing, and apply it to routinely available data to estimate the true incidence and prevalence of chlamydia infection within the Australian population. We preview in-progress work towards a yet more sophisticated methodology and outline how the approach may be extended to provide estimates for a number of other bacterial sexually transmitted infections of public health importance.

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