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.