Background and Aim

Although Australia was declared malaria free in 1981, the proximity of Australia’s Torres Strait region to malaria-endemic Papua New Guinea means there is an ongoing risk of malaria for many Australian residents. Three malaria outbreaks were declared in the Torres Strait between 2023 and 2025, the first locally acquired cases detected in the region since 2011. This study describes the public health responses which rapidly halted transmission in all three outbreaks.

Methods and Analysis

Malaria cases were defined as locally acquired if individuals reported no history of overseas travel and had positive microscopy, a positive nucleic acid amplification test or a positive rapid diagnostic point-of-care test for malaria. In each outbreak, a local public health response team arrived in community within 4 days of detection of the index case. The response included door-to-door case finding, rapid diagnostic testing, community education and mosquito harbourage spraying. The use of outbreak response records and jurisdictional laboratory data supported the response.

Outcomes

There were eight locally acquired cases across the three outbreaks. Median time from onset to case detection was 6 days (range 4-41 days). The median age was 25 years (range 11-49 years), and five cases (63%) were female. Plasmodium vivax was detected as the infecting species for six cases (75%), with the species unable to be determined for two cases. Three cases (38%) were hospitalised for a median of 4 days (range 2-4 days). No deaths, acute complications or relapses were reported. No additional locally acquired cases were identified following the declared end date of each outbreak. Local Torres Strait Island leadership and community engagement were essential to the success of the response.

Conclusion and Future actions

The prompt and comprehensive public health response to three malaria outbreaks in the Torres Strait prevented ongoing transmission and the spread of a potentially life-threatening pathogen to mainland Australia.

Aboriginal and Torres Strait Islander peoples’ health statement

Each outbreak response was conducted in partnership with local Torres Strait Island leaders and clinic staff, who enabled engagement that was culturally considered and adapted to the needs of the community. Strong collaborative involvement of all parties was central to the success of the response, including local Torres Strait Island Regional Council Environmental Health officers, Torres Strait Island health workers, cross-border communication workers and the local Primary School Principal. Local community members were highly receptive of the on-ground response and are credited with its success. While well-familiar with mosquito borne disease outbreaks, the willing engagement of communities to stop the bite prevented ongoing local transmission of malaria. Local Torres Strait Island staff involved in the response have endorsed this abstract and an ethics exemption has been obtained from the Far North Queensland Human Research Ethics Committee. One co-author identifies as a Torres Strait Islander and another as Papua New Guinean, one of whom will co-deliver the presentation.

Background and Aim: Mosquito-borne dengue and zoonotic Q fever are viral and bacterial communicable diseases, respectively, which are considered re-emerging global threats. The aim of this study was to (i) globally assess the extent of exposure (seroprevalence) of healthy children to dengue or Q fever infections, and (ii) identify dengue and Q fever infections in Australian children.
Methods and Analysis: The following analyses were conducted: (i) systematic reviews (SR) and meta-analyses (MA) of the global seroprevalence of dengue and Q fever in healthy children aged <20 years reported in the published medical literature, (ii) identification of dengue and Q fever infections in Australian children aged <16 years via a) a ten-year retrospective medical record audit (2012−2022) of cases admitted to two NSW paediatric hospitals, and b) national prospective surveillance (2022−2025) through monthly paediatrician reporting of cases to the Australian Paediatric Surveillance Unit (APSU).
Outcomes: SR and MA of 94 studies showed highest dengue seroprevalence in healthy children in Oceania (64%), Central/South America (60%), and Asia (40%), while SR and MA of 42 studies found Q fever (C. burnetii) seroprevalence was highest in the Middle East (14%). Both dengue and Q fever seroprevalence increased as the age of the children increased. The medical record audit using relevant ICD-10 codes and APSU surveillance collectively identified 11 children with dengue and seven children with Q Fever. Of cases reported to the APSU, all ten dengue cases had recently travelled to endemic countries (Indonesia and India), while all four children with Q fever had recent contact with large domestic animals in Australian rural areas.
Conclusion and Future actions: SR and MA analyses showed high global dengue and Q fever seroprevalence in healthy children. Smaller numbers of these infections were identified in Australian children. In the absence of suitable vaccines, children face elevated risk, highlighting the urgent need for stronger dengue and Q fever mitigation strategies.

Background and Aim
Buruli ulcer (BU) is a rare necrotising skin infection caused by Mycobacterium ulcerans. Treatment typically requires eight weeks of antibiotics, with surgery required for extensive disease. The psychosocial impact of BU has been investigated in low- and low-middle-income countries. With increasing case numbers and expanding endemic regions in Australia, there is a need for a qualitative study to explore the experiences of individuals with BU in Australia.
Methods and Analysis
A qualitative study using online semi-structured interviews was conducted with participants (n= 13) who received treatment for BU. Purposive sampling was used to recruit study participants. Participants resided and received care in Victoria, a known BU-endemic region in Australia, between 2023 and 2025. The study was guided by theories from descriptive phenomenology. Thematic analysis was undertaken via iterative inductive coding using ATLAS.ti software.
Outcomes
Two major themes describing the patient experience through diagnosis and during active treatment were identified. Firstly, limited awareness of BU complicates the diagnostic journey and delays diagnosis, contributing to patient anxiety. Secondly, participants experience a loss of independence due to the direct impact of the wound or antibiotic side-effects. Loss of independence impacts mental and emotional health, contributing to enduring psychosocial impacts following recovery.
Conclusion and Future actions
Ongoing work to increase awareness and reduce the incidence of BU is needed, with a focus on prevention strategies in the community and education of health care practitioners in both endemic and non-endemic areas, to minimise the significant impact of the disease. Further research exploring shorter and more tolerable treatment is recommended. Our study illustrates the severe impact of Buruli ulcer on those affected.

Background and Aim

First Nations voices have historically been excluded from shaping public health policy, practice and research. Our initiative addresses this gap by embedding Indigenous perspectives in health decision-making through First Nations Community Panels.
Communities identified the need for culturally safe, inclusive governance that moves beyond tokenistic consultation toward genuine partnership. Our aim was to develop a sustainable engagement model grounded in Indigenous governance principles.

Methods and Analysis

The First Nations Community Panels methodology was designed by an Aboriginal researcher and remains Aboriginal-led and governed. Recruitment prioritises diversity across age, gender, Nations, and cultural groups. First Nations Community Panels are an Indigenized adaptation of citizens’ juries, integrating yarning circles with structured deliberation to support transparent, collective decision-making.

The panel process follows six key steps: community engagement; a pre-panel yarning session; an Evidence Day during which panel members hear from experts and have the opportunity to ask questions; a Deliberation Day; and a co-design step where the panel members are provided with the option to develop an implementation plan with government agencies.

Conclusion and Future Actions

Panels informed Bird Flu preparedness and response by identifying community needs and guiding health authorities on how to effectively work alongside communities. This process strengthened cultural safety in program design, built trust between communities and health departments, and translated panel recommendations into actionable strategies.

We plan to expand this model to other public health priorities, evaluate its long-term impact, and share learnings to support health systems seeking genuine partnership with First Nations peoples.

This model demonstrates how Indigenous-led governance can transform institutional processes by embedding cultural authority and accountability. It offers a replicable framework for health systems seeking genuine partnership with First Nations peoples.

Background and Aim
Since early-2024, outbreaks of H5N1 clade 2.3.4.4b have been ongoing in US dairy cattle with significant consequences for animal health and the US dairy industry. There is now evidence of multiple introductions of the virus into US dairy cattle from wild birds, suggesting that even if the current outbreaks are controlled, introductions are likely to continue. The dominant route of on-farm transmission of H5N1 between cows is thought to be via direct contact with milking equipment contaminated with infectious virus from an infected animal’s milk. Understanding the resulting transmission dynamics due to this mode of infection is required to identify opportunities for optimal on-farm intervention strategies.

Methods and analysis
We develop a mathematical description of the on-farm transmission dynamics of H5N1 in dairy cattle, accounting for the infection status of animals (SEIR), and the state (contaminated, not contaminated) of milking units. We derive analytical solutions for the reproduction number, which controls the expected size and probability of an outbreak. We perform simulations using the model to investigate the impact of pre-emptive (before outbreak) and reactive measures on reducing the size of outbreaks.

Outcomes
We demonstrate that pre-emptively dividing cattle into separate milking cohorts — with cohorts kept in separate paddocks and milked in a consistent order (e.g. cohort 1 is always milked first) — substantially reduces the size of an outbreak, especially when the initial introduction is in the final cohort to be milked. Additionally, we demonstrate that frequent testing of bulk milk samples (from the central milk vat) would rapidly detect outbreaks; reactively cohorting cattle following outbreak detection would also reduce the size of outbreaks.

Conclusion and Future actions
We have developed on-farm intervention and testing strategies that would be effective at detecting and responding to H5N1 dairy farm outbreaks.

Background

Dengue is not endemic to New South Wales (NSW) and locally acquired infection represents a rare event requiring immediate public health action. In January 2026, South Eastern Sydney Public Health Unit collaborated with Health Protection NSW and NSW Health Pathology to respond to a possible locally acquired dengue case, identified within a household cluster of three other cases following recent travel to a dengue-endemic country. Although the index case had also travelled, a 29-day interval between return home and symptom onset was inconsistent with overseas acquisition.

Methods

A rapid, precautionary investigation was initiated, including detailed case history, confirmatory laboratory testing, active case finding, community engagement and environmental investigation.

Serial serological testing coordinated across multiple laboratories confirmed recent dengue infection in the index case, consistent with local acquisition. They had not travelled outside their local area in the 14 days before symptom onset. Active case finding was conducted amongst co-travellers and local residents.

Enhanced mosquito surveillance was rapidly deployed, including trapping at the case’s residence and surrounding area, species identification, dengue PCR testing, and water sampling for adult mosquito emergence. Property surveys were conducted to assess potential mosquito breeding locations. Field teams undertook doorknocking to provide information on symptoms, testing pathways, preventing mosquito bites and removing breeding locations around the home.

Outcomes

Transmission routes that were considered include exotic mosquito importation in luggage, sexual transmission, or competent local mosquito vectors. No other locally acquired dengue cases have been identified to date. The initial investigation found no exotic mosquitoes and low numbers of local mosquitoes, with negative dengue PCR testing on mosquito pools. Additional mosquito surveillance is being conducted in February 2026.

Conclusion

With increasing risk of Aedes aegypti establishment in non-endemic areas, intensive investigation as demonstrated by this case is important for early intervention to prevent ongoing local dengue transmission.

Background and Aim
Japanese encephalitis (JE) is a low‑likelihood but high‑consequence disease for which awareness is low among Australian travellers. Vaccination is recommended for travellers spending ≥1 month in endemic areas and can be considered for shorter trips with risk factors or when repeated travel is planned. These conditional recommendations often leave travellers uncertain about whether vaccination is appropriate for their circumstances. Decision aids may support improved decision‑making and increase vaccine uptake. We evaluated whether a web‑based JE vaccine decision aid (JEVaDA) improved decision‑making, knowledge and vaccine uptake compared with standard online information.

Methods and Analysis
We conducted a parallel‑group, single‑blind randomised trial among adults planning travel to JE‑endemic countries. Participants were randomised 1:1 to either JEVaDA or standard online JE information. Pre‑ and post‑intervention measures assessed decisional conflict, JE knowledge, and intention to vaccinate. Self‑reported vaccine uptake was collected in a post‑travel follow‑up survey. Analyses adjusted for baseline values, age, and sex.

Outcomes
769 participants completed pre‑ and post‑intervention assessments (mean age 44.7 years; 51.2% female). Both groups had significant reductions in decisional conflict (intervention: –10.94; comparator: –11.58; both p<0.001) with no between‑group difference (β = –0.87; 95% CI –2.93 to 1.19, p=0.407). JE knowledge improved in both groups (intervention: +2.26; comparator: +2.63; both p<0.001), with no significant difference between groups (IRR = 0.95; 95% CI 0.90–1.00, p=0.071). Positive change in vaccination intention occurred in 19.3% vs. 16.7% (aOR = 1.15; 95% CI 0.78–1.69, p=0.488). Among 348 travellers completing follow‑up after visiting JE‑risk areas, vaccine uptake was significantly higher in the decision aid group (42.9% vs. 28.3%; aOR = 2.22; 95% CI 1.36–3.61, p=0.001).

Conclusion and Future Actions
Decision aids can support clear, confident decision-making for complex, preference-sensitive vaccinations. Integrating tools like JEVaDA into travel health pathways—and adapting them for other vaccine‑preventable diseases—may enhance engagement and appropriate uptake.