Learning to Count

Abstract

Through this thesis, I describe my field placement at Health Protection NSW (HPNSW) in fulfilment of the requirements of the Master of Philosophy in Applied Epidemiology (MAE). After spending much of my first year in COVID-19 pandemic response activities, the second year of my MAE was mainly based in the Communicable Diseases Branch (CDB) of HPNSW, as a member of the team responding to other notifiable conditions in NSW. My epidemiological study project focuses on these other notifiable conditions. In this project, I reviewed the surveillance data for a range of notifiable conditions, for changes in the epidemiology that may be attributable to the events of 2020, particularly the restriction of international travel. The findings showed a decrease in the incidence of most travel-related notifiable conditions in NSW, with the notable exception of tuberculosis. In light of the lifting of travel restrictions in late 2021, these findings were presented to a range of HPNSW staff, to inform planning for future surveillance strategies in NSW. My data analysis project was driven by the Environmental Health Branch of HPNSW, but with extensive input from both CDB and the medical entomologists at the Institute of Clinical Pathology and Medical Research (ICPMR), the state arboviral reference laboratory. I reviewed the last decade of data from the NSW Arbovirus Surveillance and Mosquito Monitoring Program (ASMMP), and the corresponding human notification data for Ross River virus (RRV) and Barmah Forest virus (BFV) infections. I attended a laboratory visit to the ICPMR Medical Entomology Laboratory, and a field visit to a mosquito trapping site at Sydney Olympic Park. I also assisted with the weekly EHB reporting of ASMMP data. In CDB, I was the main contact person for vector-borne diseases for the latter half of 2021. All these activities enabled me to ground the design and analysis of these data in real world context. The findings of the project, and recommendations for the ASMMP derived from these findings, were presented to stakeholders. These finding supported the continued use of trapped mosquito counts to inform human RRV and BFV risk, and indicated that in future analyses, it could be useful to include a time lag between mosquito numbers and human notifications, which had not previously been attempted in the analysis of these data in NSW. (Please see attached under "Table of Contents" for the rest of the abstract - due to technological issues, only some of the text would load here)