Background and Aim: Building on advancements made to respiratory disease reporting in Victoria during the COVID-19 pandemic, an opportunity was identified to enhance existing public-facing respiratory reports to communicate timely and meaningful public health messages. We developed the Victorian Respiratory Surveillance Report (VRSR), which integrates surveillance intelligence from multiple sources on COVID-19, influenza, RSV and respiratory illness in a single, cohesive report.

Methods and Analysis: As the main reporting product for respiratory disease surveillance in Victoria, the VRSR was designed to deliver insightful, timely, accurate and accessible intelligence. A distinctive feature of the VRSR is its combination of data with insights, providing clear interpretation of trends. This guided narrative with expert commentary moves beyond the largely figure- or table-based formats of traditional surveillance reporting, enhancing useability for a broad public audience. The report also includes assessments of activity levels for key respiratory conditions, providing straightforward and consistent risk communication. Metrics were selected for their relevance, helping the report stay focused while presenting key information in an accessible summary. Collaboration with communications experts provided the strong design identity of the VRSR, with comprehensive visual elements included to support interpretation.

Outcomes: Since it was launched in April 2025, the report has become the primary source of respiratory disease surveillance information in Victoria. Published fortnightly, the report is one of the most viewed pages on the Victorian Department of Health’s website. Media uptake of the report has supported clear and consistent public health messaging to the broader community. Feedback consistently highlights the value the easy-to-understand data for the public. The VRSR will be strengthened through continuous improvement, with enhancements informed by user feedback.

Conclusion and Future actions: The VRSR shows the value of clear, accessible reporting. This approach can be applied to other communicable diseases, sharing insights beyond the data.

Background: Respiratory viruses are a leading cause of paediatric hospitalisation. Historically, respiratory pathogen epidemiology followed relatively predictable seasonal patterns, with year-to-year variation assessed retrospectively. The COVID-19 pandemic disrupted these patterns and highlighted limitations of traditional surveillance systems reliant on delayed, manually collected data.

Methods: A novel Communicable Diseases Platform (CDP) was used to analyse de-identified electronic medical record and laboratory data relating to respiratory virus hospitalisations from 2016–2025 at The Royal Children’s Hospital, Melbourne. The CDP integrates multiplex PCR results of 13 respiratory pathogens with admission-level clinical data, enabling real-time assessment of pathogen-specific burden. Year-to-year changes in seasonal trends and hospitalisation burden were assessed.

Outcomes: Over the 10-year study period, 26,360 respiratory pathogen-associated hospitalisations were identified. In the pre-pandemic era, respiratory pathogens demonstrated relatively stable seasonal patterns. During and following the COVID-19 pandemic, marked disruptions were observed including prolonged suppression of multiple viruses followed by major resurgences, altered peak timing and substantial shifts in hospitalisation numbers. Post-pandemic seasons were characterised by heterogeneous and dynamic changes in pathogen dominance, including unexpected spikes of Mycoplasma Pneumoniae and Bordetella Pertussis in 2024 which reflected descriptions of “mini-outbreaks” from other national and international sites. Consistent with the rollout of nirsevimab and maternal RSV vaccination, RSV-associated hospitalisations declined markedly in 2025, representing a 61% reduction compared with the 2022 peak.

Conclusion: Paediatric respiratory pathogen activity in the post-pandemic era has entered an “incomplete new normal,” with partial re-alignment toward historical seasonality but ongoing unpredictability. These changes likely relate to factors such as changes in testing practice, increased globalisation altering disease spread, altered immunisation practices and vaccine hesitancy. The CDP provides contemporaneous, granular surveillance of paediatric respiratory virus-associated hospitalisations, enabling earlier detection of emerging trends, improved preparedness for seasonal and pandemic shocks, and a shift from retrospective surveillance toward proactive, data-driven health system response.

Background and Aim: The unusual surge in human metapneumovirus (hMPV) infections observed in China during late 2024 was postulated to stem from post-pandemic waning immunity. This pattern subsequently emerged across North America, Europe, and South and Southeast Asia, disproportionately affecting children under five years of age, older adults, and immunocompromised individuals. In New South Wales, a marked increase in laboratory-confirmed hMPV cases was detected from the third quarter of 2024, prompting renewed attention to viral circulation dynamics. As hMPV remains a leading cause of acute respiratory infections globally and contributes substantially to morbidity and hospitalisation among vulnerable populations, characterising its epidemiological trends and genomic diversity is essential for strengthening surveillance, refining prevention strategies, and informing future vaccine development.
Methods and Analysis: This study employed targeted next-generation sequencing (tNGS) to generate whole-genome sequences directly from hMPV-positive clinical specimens collected between 2022-2025, bypassing the need for traditional viral culture.
Outcomes: Using this approach, 178 complete high-quality genomes were successfully recovered. Phylogenetic analysis revealed that most sequences belonged to subgenotypes A2b2 (79/178, 44%) and B2 (69/178, 39%), contrasting markedly with the contemporaneous outbreak in China, which was dominated by a single B2 subgenotype. The broader genomic diversity observed in Australia suggests differences in transmission dynamics, introduction events, or population immunity between regions.
Conclusion and Future actions: Overall, tNGS proved highly effective for obtaining complete genomes from primary clinical material, demonstrating its utility for rapid, high-resolution genomic surveillance of hMPV. These findings support the integration of tNGS into national respiratory virus monitoring frameworks to enhance real-time understanding of hMPV strain diversity, evolution, and epidemiology in Australia and to better inform future public health responses.

Background and Aim:
Viral acute respiratory infections (ARIs), including those caused by influenza, respiratory syncytial virus (RSV), and SARS-CoV-2, represent a significant health burden. Following acute phase recovery, viral-induced respiratory damage coupled with host immune dysregulation may predispose to community-acquired pneumonia (CAP) in the long-term, adding to the overall morbidity of severe viral ARIs. This study aimed to describe the incidence and timing of post-acute hospitalisation with CAP following severe ARIs.

Methods and Analysis:
This retrospective cohort study analysed all Queensland public and private hospital inpatient admissions between 2022 and 2024. We examined the relationship between initial (index) hospitalisations for COVID-19, RSV, and influenza and subsequent emergency department (ED) presentations for community-acquired pneumonia (CAP), with index admissions for other respiratory and non-respiratory admissions as a control. Descriptive statistics, time-to-event and multivariable regression analysis were used in this study.

Outcomes:
Among 845,730 patients with an index hospital admission, 7.3% of patients with an RSV index admission had a post-acute CAP hospitalisation with 24 months post discharge. This compares to a post-acute CAP incidence of 3.8% for SARS-CoV-2, 2.7% for influenza, 4.3% for other respiratory index admissions and 4.6% for non-respiratory index admissions. Sub-analysis on children under 5 years of age demonstrated a very similar incidence pattern. Patients with an index admission with RSV have 2.2 times the rate of post-acute CAP requiring hospitalisation as patients with an index admission with SARS-CoV-2 after adjusting for age group, sex, ICU admission status, co-morbidities and year of admission (HR = 2.2, 95% CI 1.9 to 2.5).

Conclusion and Future Actions:
This study demonstrates a higher incidence of post-acute CAP requiring hospitalisation following RSV compared to SARS-CoV-2 and influenza. As recent RSV vaccination has the potential to significantly reduce acute and post-acute morbidity, future follow-up studies will help assess the vaccines full impact.

Background and Aim:
Mycoplasma pneumoniae (MP) infections plummeted during COVID-19, largely attributed to social distancing. Levels remained suppressed until a global resurgence in 2023, associated with increased disease severity and drug resistance. We aimed to describe the spatiotemporal distribution of MP in Victoria before, during and after the surge.

Methods and analysis:
The SnotWatch platform receives results of PCR respiratory tests from laboratories across Victoria. We analysed results available to the platform for MP up to February 2026. From 2016–2025, 912,768 MP tests were available to Snotwatch for residents across all Victorian Statistical Area level 4 (SA4) regions, of which 7,468 (0.83%) were positive. Multiple distinct distributions were observed: pre-pandemic endemicity, near-elimination during social distancing, and a post-pandemic surge, followed by stabilisation. The post-pandemic surge lasted 21 months, peaking in September 2024, with test-positivity rate of 5.67%, after which detections subsided, averaging 0.09% test-positive since July 2025. Test positivity was highest among 5–9 and 10–14 year-olds both before and during the surge, with significant increases across all age groups during the surge (p<0.001). Using Poisson regression of positives offset by total tests, we found SA4 heterogeneity pre-surge, with a significant shift in spatial distribution during the surge (p<0.001).

Outcomes:
The post COVID-19 MP surge has now passed. However, it remains unclear whether transmission will revert to the typical 3–7-year epidemic cycle observed in developed settings. Surveillance is required to determine whether activity returns to baseline periodicity or establishes a new equilibrium, including monitoring evolutionary change and antimicrobial resistance.

Conclusion and Future actions:
SnotWatch provides a retrospective and potential prospective near real-time platform to monitor and assess epidemic evolutions and the impacts of common infectious agents. Knowledge of the “pre-test” probability of MP may help inform management of acute lower respiratory infections, including use of empiric macrolides.

Background and Aim

Information about circulating RSV types and clades and surveillance for monoclonal antibody resistance is critical for disease control in Australia. Nirsevimab was introduced in Queensland for newborns in April 2024. We aimed to describe the RSV type, clade distribution and presence of nirsevimab resistance-associated mutations in adults throughout Queensland in the 2024-2025 season.

Learning Objectives: To understand evolution and emergence of RSV clade types in Queensland after the COVID-19 pandemic and to understand the current situation and importance of ongoing genomic surveillance for potential emergence of anti-RSV monoclonal resistance-associated mutations.

Methods and Analysis

Samples from adults throughout the state were provided by Pathology Queensland from March 2024 to June 2025, preferencing those a high viral load. After RNA extraction, typing was performed by qPCR. A published amplicon-based enrichment process was used, followed by library preparation using the Illumina Nextera XT DNA kit and sequencing on Illumina devices. Analysis was performed on BaseSpace (Illumina) and the published RSV-Genoscan pipeline.

Outcomes

Of a total of 601 samples, 469 were able to be RSV A/B typed and 443 had a clade available. RSV-B accounted for 68.6% of samples through March to November 2024, driven by clades B.D.E.1, B.D.E.5 and B.D.4.1.1. From December 2024 onwards, RSV-A accounted for 53.8% of samples, with the replacement largely being driven by the A.D.1.4 clade. Although nirsevimab is adminnistered to newborns, emergence of resistance would occur at a population level, including in adults. There were no (0%) nirsevimab-resistance associated mutations detected in 152 samples with sufficient read coverage of the F-gene.

Conclusion and Future actions

Over 2024-2025, the predominant RSV type in Queensland shifted from RSV-B to RSV-A, driven mainly by the emergence of the A.D.1.4 clade, which appeared after the COVID-19 pandemic and has emerged widely in Australia. This clade has not been associated with nirsevimab resistance mutations and there was no evidence of nirsevimab resistance emerging in adults in Queensland in the early months of the rollout. Selective evolution will continue to drive the emergence of new RSV clades. Ongoing genomic surveillance is critical. This study will continue to sequence RSV samples through February 2026.

Background
Contemporary data on the true burden of human metapneumovirus (hMPV) hospitalizations in children accounting for the role of differing climate conditions, and testing variability is unknown in Western Australia (WA). This study aimed to estimate the true burden of hMPV hospitalizations across tropical, subtropical, and temperate climates in WA children.
Methods
A population-based cohort study was conducted using linked perinatal, hospitalization and routine microbiological testing data from the WA Respiratory Infections Linked Data Platform for children aged less than 15 years born in WA between 01 January 2010 and 30 April 2024. We developed and validated prediction models (logistic regression, random forest, and extreme gradient booting) using machine learning approaches Variable selection was informed by Directed Acyclic Graphs and LASSO-penalised logistic regression. Predicted probabilities were generated using extreme gradient boosting. We compared laboratory-confirmed hospitalisation rates with model-predicted rates and determined the under-ascertainment fractions across for infants, children <5 years and ≥ 5 years.
Preliminary findings
Our cohort included 668,341 hospital admissions(308,051 children), of whom 56,829 were hMPV-tested(4.1% positive). The overall true incidence was higher in tropical(3.3 per 1,000 child-years in northern tropical regions) than in temperate regions(1.5 per 1,000 child-years in southern temperate regions). Predicted incidence was higher compared to observed rates (e.g.,9.9/1,000 vs 7.2/1,000 child-years in northern tropical in infants). Overall, routine microbiological testing underestimated the true burden of hMPV by 30 – 50% in children less than 5 years of age.
Conclusions
This preliminary analysis demonstrates that hMPV represents a clinically significant, geographically heterogeneous, and substantially under-recognised cause of hospitalisation in young children in tropical and subtropical regions. Understanding the burden of hMPV and risk factors is vital to inform vaccine development and implementation policy.
Acknowledgements: We thank the staff at WA Data Linkage Services and relevant Data Custodians for providing the data used in this study.