Epidemiology of Infectious Diseases in Western Australia

I commenced the Master of Philosophy in Applied Epidemiology (MAE) in February 2015. My field placements were shared between the Communicable Diseases Control Directorate, Public Health Division at the Western Australia Department of Health (CDCD) and the Telethon Kids Institute (TKI), both located in Perth. Two of the three projects that I completed at the CDCD involved a statewide protracted mumps outbreak that went on for the duration of my MAE and reached almost 900 cases. The epidemiology of this outbreak including a discussion about vaccination is presented in Chapter 1. This satisfies the outbreak investigation requirement of the MAE. Chapter 2 comprises a late draft manuscript that explores the vaccine effectiveness (VE) of the measles-mumps-rubella vaccine among paediatric cases during the mumps outbreak. I designed and carried out a matched case-control study using paediatric outbreak cases and controls from a population database. I measured VE using a conditional logistic regression model and compared it with the screening method. Both methods yielded a very low VE this population. This is likely due to a multitude of factors that are discussed in the chapter. My work at TKI involved a data analysis using linked-administrative data on a total population birth cohort involving all children born in Western Australia between 1996-2012. I explored the burden of hospital separations that resulted from otitis media (OM), the most common infectious disease in children, and a common related procedure, myringotomy with ventilation tube insertion (MVTI). I calculated the age-specific hospitalisation rates for OM and MVTI over the study years. The second part of this analysis involved investigating the maternal and infant risk factors and population attributable fractions for OM-related hospitalisation in early life. This work was important because of its implications for practice. All of this is presented in Chapter 3. Chapter 4 is an evaluation of SmartVax, a novel, real-time Adverse Events Following Immunisation (AEFI) surveillance system using SMS text messages to communicate directly with vaccinees after their vaccination. This was the third project that I completed at the CDCD. The chapter begins with a peer-reviewed publication, Continuous active surveillance of adverse events following immunisation using SMS technology, that describes the system and analyses data outputs for children <5 years from 2011-2015. I have included the publication first to provide a brief system overview including summarised surveillance data, to give context to the evaluation since SmartVax is a relatively new and developing system. The publication is followed by the formal evaluation. Finally, I include a summary of the teaching exercises that I was involved in during my MAE. The first was a “lesson from the field” where I prepared an exercise for my fellow scholars. The exercise was useful for me and the feedback from my colleagues was positive. The second was a collaborative teaching exercise about confounding that we taught to the first year MAE scholars on their last day of courseblock. These combined activities at both placements have enriched my understanding of epidemiology while working in health and research environments

Starting to smoke: a qualitative study of the experiences of Australian indigenous youth

BackgroundAdult smoking has its roots in adolescence. If individuals do not initiate smoking during this period it is unlikely they ever will. In high income countries, smoking rates among Indigenous youth are disproportionately high. However, despite a wealth of literature in other populations, there is less evidence on the determinants of smoking initiation among Indigenous youth. The aim of this study was to explore the determinants of smoking among Australian Indigenous young people with a particular emphasis on the social and cultural processes that underlie tobacco use patterns among this group. MethodsThis project was undertaken in northern Australia. We undertook group interviews with 65 participants and individual in-depth interviews with 11 youth aged 13&ndash;20 years led by trained youth &lsquo;peer researchers.&rsquo; We also used visual methods (photo-elicitation) with individual interviewees to investigate the social context in which young people do or do not smoke. Included in the sample were a smaller number of non-Indigenous youth to explore any significant differences between ethnic groups in determinants of early smoking experiences. The theory of triadic influence, an ecological model of health behaviour, was used as an organising theory for analysis. ResultsFamily and peer influences play a central role in smoking uptake among Indigenous youth. Social influences to smoke are similar between Indigenous and non-Indigenous youth but are more pervasive (especially in the family domain) among Indigenous youth. While Indigenous youth report high levels of exposure to smoking role models and smoking socialisation practices among their family and social networks, this study provides some indication of a progressive denormalisation of smoking among some Indigenous youth. ConclusionsFuture initiatives aimed at preventing smoking uptake in this population need to focus on changing social normative beliefs around smoking, both at a population level and within young peoples&rsquo; immediate social environment. Such interventions could be effectively delivered in both the school and family environments. Specifically, health practitioners in contact with Indigenous families should be promoting smoke free homes and other anti-smoking socialisation behaviours

Coronavax : preparing community and government for COVID-19 vaccination:: a research protocol for a mixed methods social research project

Introduction Ahead of the implementation of a COVID-19 vaccination programme, the interdisciplinary Coronavax research team developed a multicomponent mixed methods project to support successful roll-out of the COVID-19 vaccine in Western Australia. This project seeks to analyse community attitudes about COVID-19 vaccination, vaccine access and information needs. We also study how government incorporates research findings into the vaccination programme. Methods and analysis The Coronavax protocol employs an analytical social media study, and a qualitative study using in-depth interviews with purposively selected community groups. Participant groups currently include healthcare workers, aged care workers, first responders, adults aged 65+ years, adults aged 30-64 years, young adults aged 18-29 years, education workers, parents/guardians of infants and young children (&lt;5 years), parents/guardians of children aged 5-18 years with comorbidities and parents/guardians who are hesitant about routine childhood vaccines. The project also includes two studies that track how Australian state and Commonwealth (federal) governments use the study findings. These are functional dialogues (translation and discussion exercises that are recorded and analysed) and evidence mapping of networks within government (which track how study findings are used). Ethics and dissemination Ethics approval has been granted by the Child and Adolescent Health Service Human Research Ethics Committee (HREC) and the University of Western Australia HREC. Study findings will be disseminated by a series of journal articles, reports to funders and stakeholders, and invited and peer-reviewed presentations.</p

Effect of a family-centered, secondhand smoke intervention to reduce respiratory illness in indigenous infants in Australia and New Zealand: a randomized controlled trial

Introduction: Secondhand smoke (SHS) is a significant cause of acute respiratory illness (ARI) and 5 times more common in indigenous children. A single-blind randomized trial was undertaken to determine the efficacy of a family centered SHS intervention to reduce ARI in indigenous infants in Australia and New Zealand. Methods: Indigenous mothers/infants from homes with ≥1 smoker were randomized to a SHS intervention involving 3 home visits in the first 3 months of the infants\u27 lives (plus usual care) or usual care. The primary outcome was number of ARI-related visits to a health provider in the first year of life. Secondary outcomes, assessed at 4 and 12 months of age, included ARI hospitalization rates and mothers\u27 report of infants\u27 SHS exposure (validated by urinary cotinine/creatinine ratios [CCRs]), smoking restrictions, and smoking cessation. Results: Two hundred and ninety-three mother/infant dyads were randomized and followed up. Three quarters of mothers smoked during pregnancy and two thirds were smoking at baseline (as were their partners), with no change for more than 12 months. Reported infant exposure to SHS was low (≥95% had smoke-free homes/cars). Infant CCRs were higher if one or both parents were smokers and if mothers breast fed their infants. There was no effect of the intervention on ARI events [471 intervention vs. 438 usual care (reference); incidence rate ratio = 1.10, 95% confidence intervals (CI) = 0.88-1.37, p = .40]. Conclusions: Despite reporting smoke-free homes/cars, mothers and their partners continue to smoke in the first year of infants\u27 lives, exposing them to SHS. Emphasis needs to be placed on supporting parents to stop smoking preconception, during pregnancy, and postnatal

Standardising and assessing digital images for use in clinical trials: A practical, reproducible method that blinds the assessor to treatment allocation

With the increasing availability of high quality digital cameras that are easily operated by the non-professional photographer, the utility of using digital images to assess endpoints in clinical research of skin lesions has growing acceptance. However, rigorous protocols and description of experiences for digital image collection and assessment are not readily available, particularly for research conducted in remote settings. We describe the development and evaluation of a protocol for digital image collection by the non-professional photographer in a remote setting research trial, together with a novel methodology for assessment of clinical outcomes by an expert panel blinded to treatment allocation

Continuous active surveillance of adverse events following immunisation using SMS technology

INTRODUCTION On-going post-licensure surveillance of adverse events following immunisation (AEFI) is critical to detecting and responding to potentially serious adverse events in a timely manner. SmartVax is a vaccine safety monitoring tool that uses automated data extraction from existing practice management software and short message service (SMS) technology to follow-up vaccinees in real-time. We report on childhood vaccine safety surveillance using SmartVax at a medical practice in Perth, Western Australia. METHODS Parents of all children under age five years who were vaccinated according to the Australian National Immunisation Schedule between November 2011 and June 2015 were sent an SMS three days post administration to enquire whether the child had experienced a suspected vaccine reaction. Affirmative replies triggered a follow-up SMS requesting details of the reaction(s) via a link to a survey that could be completed using a smartphone or the web. Rates of reported AEFI including fever, headache, fatigue, rash, vomiting, diarrhoea, rigours, seizures, and local reactions were calculated by vaccination time point. RESULTS Overall, 239 (8.2%; 95% CI 7.2-9.2%) possible vaccine reactions were reported for 2897 vaccination visits over the 44 month time period. The proportion of children experiencing a possible AEFI, mostly local reactions, was significantly greater following administration of diphtheria-tetanus-pertussis-poliomyelitis vaccine at 4 years of age (77/441; 17.5%; 95% CI 13.9-21.0%) compared to the vaccinations given at 2-18 months (p<0.001). Across all time points, local reactions and fatigue were the most frequently reported AEFI. CONCLUSION Automated SMS-based reporting can facilitate sustainable, real-time, monitoring of adverse reactions and contribute to early identification of potential vaccine safety issues.This work was supported by the Western Australia Department of Health

A protracted mumps outbreak in Western Australia despite high vaccine coverage: a population-based surveillance study

In 2007–08, a genotype J mumps outbreak occurred among Aboriginal people in northern Western Australia, despite high vaccine coverage. In March, 2015, a second protracted mumps outbreak occurred in northern Western Australia and spread widely across rural areas of the state. This time the outbreak was caused by a genotype G virus and again primarily affected Aboriginal people. We aimed to describe the epidemiology of this outbrea

Australian Aboriginal children have higher hospitalization rates for otitis media but lower surgical procedures than non-Aboriginal children: A record linkage population-based cohort study

Introduction Otitis media (OM) is one of the most common infectious diseases affecting children globally and the most common reason for antibiotic prescription and paediatric surgery. Australian Aboriginal children have higher rates of OM than non-Aboriginal children; however, there are no data comparing OM hospitalization rates between them at the population level. We report temporal trends for OM hospitalizations and in-hospital tympanostomy tube insertion (TTI) in a cohort of 469,589 Western Australian children born between 1996 and 2012. Materials and methods We used the International Classification of Diseases codes version 10 to identify hospitalizations for OM or TTI recorded as a surgical procedure. Using age-specific population denominators, we calculated hospitalization rates per 1,000 child-years by age, year and level of socio-economic deprivation. Results There were 534,674 hospitalizations among 221,588 children hospitalized at least once before age 15 years. Aboriginal children had higher hospitalization rates for OM than non-Aboriginal children (23.3/1,000 [95% Confidence Interval (CI) 22.8,24.0] vs 2.4/1,000 [95% CI 2.3,2.4] child-years) with no change in disparity over time. Conversely non-Aboriginal children had higher rates of TTI than Aboriginal children (13.5 [95% CI 13.2,13.8] vs 10.1 [95% CI 8.9,11.4]). Children from lower socio-economic backgrounds had higher OM hospitalization rates than those from higher socio-economic backgrounds, although for Aboriginal children hospitalization rates were not statistically different across all levels of socio-economic disadvantage. Hospitalizations for TTI among non-Aboriginal children were more common among those from higher socio-economic backgrounds. This was also true for Aboriginal children; however, the difference was not statistically significant. There was a decline in OM hospitalization rates between 1998 and 2005 and remained stable thereafter. Conclusion Aboriginal children and children from lower socio-economic backgrounds were over-represented with OM-related hospitalizations but had fewer TTIs. Despite a decrease in OM and TTI hospitalization rates during the first half of the study for all groups, the disparity between Aboriginal and non-Aboriginal children and between those of differing socioeconomic deprivation remained.This study was funded through a National Health and Medical Research Council (NHMRC;www.nhmrc.gov.au) Project Grant (APP1045668). CCB is funded by National Health and Medical Research Council Fellowship (1111596) and HCM is funded by National Health and Medical Research Council Fellowship (1034254)