Breathing Infection: Unravelling respiratory riddles and riding infectious waves in South Eastern Sydney

Abstract

This thesis presents four projects and public health activities from my field placement at the South Eastern Sydney Local Health District's (SESLHD) Public Health Unit (PHU), fulfilling the competencies for my Master of Philosophy (Applied Epidemiology) (MAE) at the Australian National University. In early 2023, I participated in the investigation of a tuberculosis (TB) outbreak in Sydney, which underscored the value of genomic sequencing and informed my evaluation of TB contact data quality in the state Notifiable Conditions Information System (NCIMS) against local clinic records. This evaluation revealed deficiencies in NCIMS data, and I was able to review the points at which contacts dropped out of the screening pathway. In January 2024, the PHU responded to an outbreak of Legionella pneumophila serogroup 1 in 15 people who had visited the Sydney central business district (CBD), for which I was the lead epidemiologist. I coordinated outbreak management team meetings, produced situation reports, maintained a case line list, and collaborated with the Ministry of Health to perform geocoding and mapping. As part of the post-pandemic response, I conducted an evaluation of the District's existing Acute Respiratory Infections (ARI) report. This assessment focused on the report's timeliness, usefulness, and readability. Following the evaluation, I rebuilt the report using R statistical software and based on the World Health Organization's (WHO) guidelines for respiratory surveillance, to enhance the report's utility and relevance post-pandemic. This included developing workplace instructions and introducing automation to increase efficiency. My final project examined factors associated with delayed hepatitis B (HBV) diagnosis in SESLHD using linked population-based data. The findings provided evidence to inform local policy and prevention activities. Additionally, I engaged in various public health activities, including teaching epidemiology, participating in seasonal arbovirus control, touring the Australian Nuclear Science and Technology Organisation (ANSTO) for biopreparedness activities, developing a new reporting format for acute respiratory disease outbreaks in aged care facilities, establishing a local R club, creating outbreak documentation templates, managing infectious disease cases, and participating in field work including legionella sampling, cruise ship inspections, and a sex on premises site visit. These experiences enriched my understanding of applied epidemiology and contributed to public health operations and decision-making.