Background: Respiratory syncytial virus (RSV) infection and associated hospitalisations represent a significant public health burden. In Australia, the hospitalisation rate for RSV from 2009 to 2017 was estimated at 54.8 per 100,000 population, with higher rates observed in high-risk groups such as children under 5 years and adults over 75 years.
In 2024, the Western Australia Government funded an RSV infant immunisation program, offering nirsevimab (Beyfortus) immunisation during the temperate winter season. However, the Kimberley and Pilbara regions in northern tropical Western Australia (WA) have historically shown variation in this winter seasonality.

Methods: An ecological study with time-series analysis is being conducted to document RSV seasonality in WA from January 1, 2012, to December 31, 2024. The study utilises RSV-associated hospitalisation records (Emergency Department Data Collection, Hospital Morbidity Data Collection) and RSV notification data (WA Notifiable Infectious Diseases Database), to document, analyse, and compare RSV seasonality in northern WA to the rest of WA.
This ongoing study will also utilise nirsevimab immunisation records (Australian Immunisation Register) to assess the impact of nirsevimab on RSV seasonality during 2024.

Results: Preliminary analysis indicates that RSV seasonality varies between northern WA and the rest of WA, with northern WA not following the winter seasonality seen in the rest of WA.
In northern WA, variation is seen from the rest of WA and between northern regions. In the generally tropical Kimberley region, ongoing transmission of RSV is observed without any clear seasonality. In the Pilbara region, transmission of RSV outside the winter season is evident, with the region experiencing prolonged seasonality.

Conclusions: Seasonal variation for RSV transmission outside the typical winter season is observed in the tropical regions of WA. Continued provision of RSV immunisation programs should be considered year-round in the northern regions of WA.

Background
Evidence synthesis in infectious diseases research often involves comparing multiple interventions to identify the most effective intervention. However, it is unclear which statistical methods are used for these comparisons across multiple studies and if these methods are implemented appropriately. This scoping review provides an overview of how comparisons of multiple interventions are synthesized in infectious diseases research.

Methods
A systematic search was conducted in PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews. Systematic reviews were included if they quantitatively synthesized three or more interventions for the prevention or treatment of infectious diseases.

Preliminary results
Of the 8160 records identified, 425 systematic reviews were eligible after full text screening. A random sample of 200 systematic reviews was selected for data extraction: 100 each from 2015–2019 and 2020–2024. This ensured representation of pre-COVID infectious diseases. Systematic reviews of interventions for hepatitis (n=29) and COVID-19 (n=32) were the most common in the periods 2015–2019, and 2020–2024, respectively. Therapeutic interventions were synthesized in 153 systematic reviews and preventive treatments in 47. The median number of interventions per systematic review was 6.0 (IQR: 4.0, 10.25). For statistical comparison of interventions, 34 systematic reviews used pairwise meta-analyses, 82 used network meta-analyses, and 84 used both. Most meta-analyses (n=189) used aggregated data. Of the 166 that used network meta-analysis models, 82 were implemented in a Bayesian framework, 42 assessed the transitivity assumption, 111 assessed the consistency assumption. Across both pairwise and network meta-analyses, 147 (73.5%) evaluated heterogeneity.

Conclusion
Pairwise and network meta-analysis models with aggregate data are commonly used in infectious diseases research. However, the key assumption underlying network meta-analysis methods (i.e., transitivity) is rarely reported. Further understanding of how these methods are implemented and reported will facilitate appropriate guidance for synthesis of multiple treatments in infectious diseases research.

Abstract
Background: Evidence suggests that pathogens may influence pain perception and regulation; however, no study has explored the relationship between antibodies to infectious agents and multisite chronic musculoskeletal pain. Therefore, this study aimed to investigate the association between infectious agent seropositivity and multisite chronic musculoskeletal pain.
Methods: Participants (n=6,814; mean [SD]age, 56.5[8.2] years; females [52.9%]) in the UK Biobank were included. Multiplex serology panel measuring serum immunoglobulin G antibody levels against 20 infectious agents was performed at baseline. Chronic pain (≥3 months) in the knee, neck/shoulder, hip, back, or ‘all over the body’ was assessed at baseline and follow-up. Participants were grouped by number of chronic pain sites: no chronic pain, chronic pain in 1-2 sites, or ≥3 sites. Multinomial logistic regression and mixed-effect multinomial logistic regression models were used for the analyses.
Results: The seroprevalences of the 20-infectious agents ranged from 0.2% to 95.4%. In multivariable analyses, seropositivity for Epstein-Barr Virus (EBV), Human T-Cell Lymphotropic Virus Type-1 (HTLV-1), and Chlamydia Trachomatis was cross-sectionally associated with chronic pain in ≥3 sites compared to those without chronic pain. In longitudinal analyses, EBV [relative risk ratio (RRR)=1.96, 95%CI:1.05−3.64] and Chlamydia Trachomatis [RRR=1.31, 95%CI:1.04−1.65] were also associated with chronic pain in ≥3 sites. Additionally, participants with single and multiple infectious agent seropositivity were associated with chronic pain in ≥3 sites, but not in 1-2 sites.
Conclusion: The seropositivity of EBV and Chlamydia Trachomatis is associated with multisite chronic musculoskeletal pain. These findings suggest that infectious agents may play a role in the pathogenesis of widespread chronic pain

Background
Measles infections cause significant morbidity and mortality in children, especially in low- and middle-income countries (LMICs). The WHO recommends the first of two doses of measles-containing vaccine (MCV) from 9-12 months of age, while infants too young to be vaccinated are thought to be protected by maternal antibodies. However, recent outbreaks in some LMICs have greatly impacted infants <9 months old, indicating a potential immunity gap in young infants. Population immunity can be characterised through seroprevalence studies which directly measure measles antibody levels. Our systematic review and meta-analysis described measles seroprevalence in infants <9 months in LMICs.

Methods
We searched ten databases and registers for journal articles and conference abstracts published between 01/01/2018-25/12/2024. We included observational studies presenting measles antibody seroprevalence data from infants <9 months old in LMICs. We excluded studies from high-income countries, non-observational studies and non-original research. Studies underwent dual reviewer screening and risk of bias assessment using an adapted Joanna-Briggs Institute tool. Seropositivity estimates were pooled using a random-effects inverse variance model. Subgroup analyses included country income level, MCV coverage and measles incidence.

Results
Among 1421 studies identified, 34 were included. Most studies were from middle-income countries (n=30/34) and hospital/health-centre based (n=22/34). Most studies had low/moderate risk of bias (n=33/34). The meta-analysis included 20 studies (N=8230 infants) with high heterogeneity. Pooled seropositivity was highest at birth (81%, 95% CI: 75-88), decreasing to 30% (95% CI: 24-35) by four months, and was lowest at seven months (18%, 95% CI: 0-41). Subgroup analyses showed minimal differences between categories.

Conclusions
Seventy percent of infants are seronegative by four months of age, therefore being unprotected from measles before their first vaccine dose. In the era of stalling measles elimination efforts, early MCV administration could be considered in some settings to provide sustained protection throughout infancy.

Background: Epidemiologists play a crucial role in pandemic preparedness planning, yet focused training in this area is limited. We aimed to develop and pilot a pandemic preparedness planning workshop for the training of students enrolled in the Master of Philosophy in Applied Epidemiology (MAE) Program.
Methods: The need for this training was identified through a curriculum review and discussion with experts. The project was initiated through collaboration between the MAE program and the World Health Organization (WHO). The WHO provided drafts of the materials, and we joined the technical advisory group and provided comments in writing and via online meetings to finalise the materials adaptable to different contexts.
To ensure the relevancy of the materials to the Australian context, inputs from an advisory group, researchers, and learning designers were sought. We used the decolonisation and equity lens in the design of the workshop. The workshop was piloted in February 2025 and evaluated by analysing data collected from the facilitators and participants’ survey and focus group.
Results: The final learning outcomes included aspects of planning, leadership and management, social determinants of health, multisectoral and one health approach, and communication. Substantial changes were made to the content of scenarios and aspects of stakeholder engagement, social determinants of health and communication. The workshop consisted of 10 hours of scenario-based training. There were seven scenarios that required participants to collaboratively develop components of a pandemic preparedness plan. Data on the evaluation of the workshop will be presented at the time of presentation as we are still collecting data.
Conclusion: Collaborations with relevant stakeholders enhance the usefulness and relevance of training materials. Including pandemic preparedness planning in epidemiology curricula will better equip the next generations of epidemiologists to manage future epidemics and pandemics.

Background
Campylobacteriosis, a leading cause of bacterial gastroenteritis in New Zealand (NZ), is traditionally associated with contaminated poultry consumption. However, drinking water, particularly from private supplies, has emerged as a significant source of infection. Private water supplies, which remain largely unregulated under the Water Services Act 2021, can contribute to disease outbreaks, especially in rural areas. This study investigates the relationship between water supply characteristics and Campylobacteriosis notification rates.
Methods
Cross-sectional Poisson regression models were used to assess the impact of water supply type, rurality, livestock density, and extreme weather events on Campylobacteriosis rates at the meshblock scale (the smallest geographic unit in NZ). We analysed publicly notified cases of Campylobacter infection from 2015 to 2019.
Results
The study found that private water supplies in rural areas with high dairy cattle density were significantly associated with increased Campylobacteriosis rates (Relative Risk (RR) = 2.21, 95% CI: 1.60-3.05) compared to urban areas with public water supplies. We also observed a significant positive association between dairy cattle density and increased campylobacteriosis incidence in private rural water supplies. Low dairy density is associated with an 18% higher risk (RR = 1.18, 95% CI: 1.04-1.34), medium density with a 17% higher risk (RR = 1.17, 95% CI: 1.03-1.33), and high density with a 47% higher risk (RR = 1.47, 95% CI: 1.28-1.69) compared to areas with no dairy cattle.
Conclusion
The findings suggest a significant role of private water supplies in rural areas, especially those with high dairy farming density, in the risk of Campylobacteriosis. These results highlight the urgent need for better land use management, monitoring and support systems for people using private water supplies in rural areas to reduce the risk of Campylobacter infection and protect public health.

Background
Digital contact tracing (DCT) interventions have been deployed at unprecedented scale during COVID-19. However, no comprehensive appraisal of the evidence exists to date regarding their effectiveness. We aimed to systematically review the global literature for a holistic understanding of DCT effectiveness during COVID-19, and to identify factors that enabled or hindered its effectiveness.
Methods
We searched six databases for peer-reviewed literature relevant to the evaluation of DCT interventions during COVID-19 (January 2024) (CRD42021268586). We compiled implemented DCT interventions from grey literature. Effectiveness appraisals, different operationalizations, measurements, and definitions of DCT effectiveness, as well as associated factors were synthesized qualitatively. Study quality was assessed using the Mixed Methods Appraisal Tool. We followed Cochrane and PRISMA guidance.
Findings
We identified 133 studies evaluating 121 different DCT implementations. Seventy-three (60%) studies found DCT to be effective, mostly when evaluating epidemiological impact metrics. Public trust emerged as crucial for DCT to be effective, which requires high and enforceable data safety and privacy standards, clear and transparent communication, high accuracy and reliability of the intervention, and an acceptance-enhancing implementation approach of other pandemic response measures by public health authorities more broadly. Most evaluations took place in high rather than low-resource settings.
Conclusion
While technical performance matters, DCT effectiveness primarily depends on a relatively small number of non-technical drivers centred around public trust. DCT should only be implemented as integrated part of a broader public health framework. Our findings hold important insights for the design, implementation, and evaluation of other digital technology for pandemic response.

Background: In patients with post-acute sequelae of COVID-19 (PASC), depression has been associated with symptom severity, duration since infection, and ongoing functional impairment. However, interconnections between these factors remain inadequately understood.
Objectives: This study explored the roles of depressive symptoms in moderating and mediating relationships between post-COVID-19 conditions and functional capacity.
Methods: The PERCEIVE study recruited 1,794 participants from Victoria and Tasmania through online advertisements for a cross-sectional study. Of these, 461 participated in the longitudinal study. Post-COVID-19 duration and symptoms were recorded, and depressive symptoms and functional capacity were self-reported using the 9-item Patient Health Questionnaire and the Duke Activity Status Index (DASI). The association of depression with functional capacity was explored using ordinary least squares (OLS) regression, Sobel-Goodman tests, and 1,000 bootstrap iterations. Longitudinal data assessed changes in functional capacity and depressive symptoms, with mediation analysis using mixed models.
Results: Participants had a mean DASI score of 35 (SD 21). Fatigue (18%), shortness of breath (11%), and chest pain (6%) were common, with severe depression linked to fatigue (93%) and shortness of breath (66%). The severity of post-COVID-19 symptoms was associated with severe depression (β = 6.31, CI [5.42, 7.21]) and reduced functional capacity (β = -6.40, CI [-9.20, -3.61]), with depression mediating 36% of the association. PASC was associated with higher depression scores (β = 2.06, CI [1.15, 2.97]) and lower functional capacity (β = -3.99, CI [-6.21, -1.77]), with depression mediating 51% of the association between PASC and functional capacity. The longitudinal analysis confirmed that depression mediates the relationship between PASC and the evolution of functional capacity (unstandardized estimate = -5.16, p < 0.001).
Conclusion: Depression plays a key role in exacerbating post-COVID-19 functional impairment. This observation underscores the need for targeted physical and mental health interventions to enhance long-term recovery for those with severe conditions.