Applied Epidemiology in the Top End and Timor Lorosa'e

Abstract

During 2015 and 2016 I undertook the Master of Philosophy in Applied Epidemiology (MAE) while continuing at the Northern Territory (NT) Centre for Disease Control (CDC) as the OzFoodNet (OFN) epidemiologist. I completed projects which form part of the requirement for attaining this degree and which taught the skills essential for good public health practitioners. In addition to the numerous routine suspected foodborne outbreak investigations I led as chief investigator and OFN epidemiologist, I conducted two cohort studies which displayed my competence to investigate acute public health events. The first outbreak I investigated was an outbreak of Salmonella Saintpaul gastroenteritis amongst students who attended a school camp in a remote area of the NT. The results of this investigation suggested food or drink at the camp was contaminated by environmental Salmonella. There were multiple possible mechanisms for contamination to occur due to poor food safety knowledge, poor hygiene and structural deficiencies. I recommended that those preparing food in campgrounds and outdoor settings have appropriate knowledge of safe food handling procedures and recognise the risks of contaminating food or water with pathogens from the environment and appropriately maintaining facilities for food preparation and service. The second cohort study I conducted was while investigating an outbreak of salmonellosis (S. Typhimurium 9) associated with consumption of contaminated duck prosciutto at a restaurant. My investigation showed that scientific principles underpin safe food handling processes and it is important not to deviate from safe methods, particularly when preparing high risk foods. I evaluated the syndromic surveillance of adult gastroenteritis at Royal Darwin Hospital (RDH). I made a number of recommendations to formalise public health responses to alerts and to consider adjusting thresholds. Some outcomes of this evaluation are already being implemented. I conducted an epidemiological study where I used short message service (SMS) to follow up people notified to the Darwin CDC with campylobacteriosis, with the aim of detecting point-source outbreaks and estimating overseas acquisition. This project did not detect any outbreaks but estimated that at least 21% of campylobacteriosis cases were acquired overseas. As a result of this project, SMS has increasingly been used at CDC for disseminating information and is now the primary method for following up contacts as part of our measles public health response. For my data analysis project I analysed a dataset of patients diagnosed with tuberculosis (TB) at the Bairo Pite Cinic (BPC) in Dili, Timor-Leste. The most obvious finding from my project was that data quality was poor and large amounts of data were missing. I rationalised the number of variables collected and created a new data dictionary by generating categorical variables from variables that were previously free-text. At the time of writing, a new database was under construction based on the rationalised set of variables and data dictionary I created. The ultimate public health impact of my work will be a new database and reporting tool that is simple to use and acceptable in a limited resource setting. The findings of my project will enable the BPC to more efficiently record information from cases of TB diagnosed at the clinic. This thesis presents my experience during the MAE program, the skills and knowledge I attained and the impact this had on public health in the NT.