Background and Aim
The Government of Vietnam is committed to introduce the pneumococcal conjugate vaccine (PCV) into the National Expanded Programme on Immunization (NEPI) in 2026. This study evaluates the cost-effectiveness and budget impact of introducing PCV into Vietnam’s NEPI to inform NEPI expansion in this Gavi-graduated middle-income country.

Methods and Analysis
A decision-tree Markov model was used to estimate the cost-effectiveness of 13-valent PCV (PCV13) and 10-valent PCV produced by the Serum Institute of India (PCV10-SII), compared with no vaccination from a societal perspective. PCV13 and PCV10-SII were assumed to have similar protection effects, as both cover the most prevalent serotypes in Vietnam. We assumed 90% PCV coverage nationwide with 2+1 schedule. Cost data were derived from local hospital records, survey data collected from caregivers, and government reports, while disease burden and other parameters were obtained from published literature. The budget impact analysis was conducted to estimate the net and total costs to the health system in 2026-2030 under different scenarios. Sensitivity analysis was conducted.

Outcomes
Introducing either PCV13 or PCV10-SII could avert approximately 1,070 pneumococcal deaths (78% reduction) and 255,000 cases (33% reduction) in the first five years of a single birth cohort. At UNICEF prices (US$4.22 per dose for PCV13 and US$2 for PCV10-SII), both vaccines were cost-saving compared with no vaccination and remained cost-effective at the Vietnam market price of PCV13 (US$53.38 per dose). Sensitivity analyses indicated robust results when varying all model parameters. Over the next five years, the net budget impact of PCV10-SII introduction (US$5.4 million) was 11.9% of that of PCV13 (US$45.2 million).

Conclusion and Future Actions
Introducing either PCV13 or PCV10-SII is cost-saving compared with no vaccination, supporting early nationwide introduction with high coverage. Vietnam needs to work with UNICEF to secure favorable pricing and consider accelerating the licensing of PCV10-SII.

Background

In the Pacific, sociocultural norms and caregiver dynamics play a significant role in health-seeking behavior; however, limited evidence exists on immunization compliance in urban Fiji. This study explored knowledge, perceptions, and awareness of immunization, service delivery experiences, and key enablers and barriers influencing childhood immunization uptake in Suva, Fiji.
Methods and Analysis
A qualitative study design was employed using survey questionnaires and key informant interviews across four urban health facilities: Raiwaqa, Nuffield, Samabula, and Lami Health Centre’s MCH clinics. A total of 29 participants were included, comprising 16 healthcare workers and 13 parents or caregivers.
Findings indicated generally high awareness of the importance of immunization among caregivers and healthcare workers; however, gaps were observed in understanding immunization schedules, vaccine purpose, and the consequences of delayed or incomplete vaccination. Key barriers included competing caregiving responsibilities, limited family support, communication gaps between providers and communities, clinic wait times, staffing constraints, challenges in tracing defaulters, and occasional vaccine stock-outs.
Outcomes
Enablers included trust in healthcare workers, clear and culturally appropriate messaging, proactive nursing practices, community support, and outreach services such as shift clinics and home visits.
Conclusion and Future Actions
The study recommends strengthening immunization service delivery through increased staffing of zone nurses, expansion of shift clinics and mobile outreach, improved documentation and register management, and ensuring consistent vaccine supply. Enhanced caregiver education should begin during antenatal care and continue throughout child health visits, focusing on immunization schedules, vaccine benefits, side effects, and timeliness. Ongoing Expanded Program on Immunization (EPI) training for healthcare workers, improved communication skills, and the use of information, education, and communication materials are essential. Leveraging mass media and social media platforms, offering incentives to support attendance, and empowering community health workers for follow-up and health education are critical strategies to improve immunization uptake and coverage in urban Fiji.

Background and Aim
Public health responses to COVID-19 frequently relied on rapid dissemination of accurate information, assuming that knowledge would translate into compliance. Such approaches often frame risk as an individual decision-making problem. However, in rural PNG settings, responses to health emergencies are shaped by relational systems, spiritual worldviews and material conditions that influence how risk is understood and acted upon. This study aims to explore how rural communities in PNG navigated COVID-19 risk within their everyday realities.

Methods and Analysis
Qualitative research was conducted in two rural communities, including 90 participants in Balimo, Western Province, and Tari, Hela Province. Using Indigenous and participatory approaches such as storytelling, communicative ecology mapping, and photovoice, the study examines how health information circulated through relational networks, community practices, and local ways of knowing. Analysis focused on understanding the social, spiritual, and material factors shaping community responses rather than treating communication as a technical delivery exercise.

Outcomes
Findings demonstrate that responses to COVID-19 were shaped not only by official messages but by relational trust, food security, mobility constraints, communal obligations, and access to resources. Trust operated primarily through kinship networks, churches, and local leadership rather than institutions alone. Accessibility extended beyond media exposure to include the capacity to reach people, places, and resources necessary for action. Collaboration between communities, local actors, and formal systems was central to enabling collective response. Where relational engagement and material support were limited, information alone proved insufficient and ineffective.

Conclusion and Future Actions
Grounded in rural PNG, these insights highlight the need to move beyond individualistic approaches to public health emergencies. Future strategies should centre relational trust, community access, and collaborative action, leveraging local knowledge systems and networks to strengthen resilience and improve health outcomes during future crises.

Background and aim
Vector-borne diseases are a major cause of morbidity and mortality in Papua New Guinea (PNG). Strengthening Integrated Surveillance and Response for Vector‐borne Diseases in Melanesia (STRIVE) was created to address this need by improving vector-borne disease surveillance and enabling rapid public health action in PNG.

In STRIVE, sentinel site sampling of febrile patients presenting to health facilities is determined by patient load and staff workload capacity. This approach can lead to oversampling at sites with low risk, or undersampling at sites where threats are emerging. This project aimed to review and improve resource allocation to optimise sampling and testing at locations most in need of surveillance support.

Methods and analysis
We applied a previously developed (Le and Baker) Bayesian adaptive sampling framework to the STRIVE surveillance data, collected from eight sentinel sites across PNG and consisting of ~18,000 febrile patient records. This framework uses posterior probability risk thresholds and was piloted for malaria resistance using the Plasmodium falciparum kelch13 gene (Pfk13) C580Y molecular marker, which is increasing globally but remains poorly characterised in PNG. Model outputs were incorporated into an interactive dashboard to inform resource allocation and help support decision-making.

Outcomes
We found substantial heterogeneity between sites in total malaria burden, PfK13 resistance prevalence, environmental characteristics, and sampling volumes. These findings helped inform where risk is consistently high and well-characterised from sites where new threats may be emerging. Fixed risk thresholds from the Bayesian framework were found to not fully represent site diversity, while adaptive thresholds produced sampling recommendations that better aligned with site-specific needs.

Conclusion and future actions
This work provides a foundation for more optimal resource allocation to facilitate vector-borne sentinel surveillance in PNG. Future actions will include real-time updating of data to inform earlier detection of site-specific risk and targeted health responses.

Background and Aim: With declining vaccine coverage and rising disease rates, strengthening trust and confidence in routine childhood vaccines in Papua New Guinea (PNG) is critical. Supported by the Australian Government and UNICEF in partnership with the PNG National Department of Health and the Eastern Highlands and Morobe Provincial Health Authorities, and building on Vaccine Champions Programs implemented elsewhere, we adapted, delivered and evaluated a vaccine education and communication training program for health workers and community/religious leaders to promote routine childhood immunisation in PNG.
Methods and Analysis: The PNG Vaccine Champion Plus Training Program included four phases underpinned by co-design principles: 1) consultative meetings to understand local immunisation context; 2) adaptation of previous Vaccine Champions training materials with stakeholders; 3) multi-level vaccine education and communication training using flipcharts and role-play; and 4) support for champions to deliver community vaccine discussion sessions over four months. We evaluated the reach, effectiveness, adoption, implementation and maintenance of the program with questionnaires and field notes. Primary outcomes included Champions' knowledge, communication, self-efficacy, trust in routine childhood vaccines and satisfaction.
Outcomes: In September 2025 we trained 8 master trainers (4/8 female), and in November 2025 they trained 96 Champions (38/96 female); 63 health workers and 33 community/religious leaders. Between November 2025 and February 2026, Champions conducted 34 sessions, reaching over 2850 community members. Most of the 96 Champions trained (97%) were satisfied or very satisfied with the training. Training increased Champions’ communication self-efficacy, with 65% describing themselves as ‘very confident’ in initiating conversations with a vaccine-hesitant person post-training. Community/religious leader Champions reported a 38-percentage point increase in perceived importance of vaccines.
Conclusion and Future Actions: Training health workers and community/religious leaders with a contextually adapted Vaccine Champions program improved vaccine knowledge, communication skills and confidence. This program could be adapted to other PNG provinces.

Background and Aim
In Timor-Leste, high burdens of child undernutrition and enteric illness persist despite water, sanitation, and nutrition programmes. While interventions emphasise infrastructure and behaviour change, less attention has been given to how households perceive and manage risks related to food, water, and environmental hygiene. Understanding these practices is critical for improving enteric infection prevention and child health. This study examined household food, water, and hygiene practices through a One Health lens, focusing on how human behaviour, environmental conditions, and animal presence intersect to shape infection risk and protective strategies.

Methods and Analysis
We conducted a qualitative study using in-depth, semi-structured interviews with 34 female caregivers in urban and rural settings in Timor-Leste. Interviews were conducted in Tetum between August and October 2025 and explored water use, food preparation and storage, waste management, seasonality, and perceived links between environmental conditions and child health. Transcripts were analysed using inductive thematic analysis, followed by an abductive interpretive phase informed by One Health and environmental health literature.
Outcomes
Households actively negotiated food and water safety under intermittent supply, seasonal variability, pest exposure, and limited infrastructure. Participants described selective risk-reduction strategies, including prioritising boiled water for infants, differentiating water storage by purpose, limiting storage duration, and adapting preservation practices during hotter months. Kitchens emerged as key human–environment interfaces where hygiene practices were shaped by material constraints rather than knowledge gaps, influencing exposure pathways for enteric pathogens. Practices such as food sharing, waste repurposing as animal feed, and reliance on social networks illustrated interconnected human–animal–environment systems shaping vulnerability and resilience.
Conclusion and Future Actions
Findings highlight the importance of One Health approaches that integrate water systems, food environments, animal management, and community support structures. Public health interventions aligned with caregivers’ experiential knowledge and designed to address structural constraints are more likely to strengthen infection prevention and achieve sustained improvements in child health in fragile settings.

Background and Aim

The oral rotavirus vaccine, Rotavac, was introduced into the Expanded Programme on Immunization (EPI) in Timor-Leste in December 2019. A national rotavirus survey conducted prior to vaccine introduction (2014 – 2016) demonstrated a high burden of severe rotavirus disease among children <5 years. However, rotavirus surveillance and post-introduction evaluation have been limited, creating an evidence gap regarding vaccine impact. Aim to determine the burden of severe rotavirus disease among children <5 years following Rotavac introduction. Specific objectives are to describe clinical presentations and outcomes, assess age, seasonal distribution, identify circulating rotavirus genotypes, and estimate vaccine effectiveness.


Methods and Analysis

Prospective hospital-based case surveillance study at six health facilities. Participant enrolment is ongoing from October 2025 to June 2027. Children aged <5 years admitted with acute watery diarrhoea (<10 days duration) are eligible for enrolment. Following informed consent, demographic, clinical, and vaccination data are collected, and stool samples obtained within 48 hours of admission. Samples are tested for rotavirus using ELISA and nucleic acid testing at the National Health Laboratory in Dili, with genotyping conducted at the Murdoch Children’s Research Institute in Melbourne, Australia. Primary data analysis will focus on the proportion of acute watery diarrhoea episodes requiring hospitalisation that are positive. Data will be presented by month and/or season, geographical distribution, gender and age group. Test-negative case-control methodology will be used to estimate vaccine effectiveness.


Outcomes

This study will generate updated estimates of rotavirus disease burden in Timor-Leste in the vaccine era, describe circulating genotypes, and provide estimates of real-world Rotavac vaccine effectiveness in this setting. Methods will support health systems strengthening routine surveillance activities.


Conclusion and Future Action

This evaluation will provide evidence to support and strengthen ongoing rotavirus surveillance and inform national immunisation policy, supporting a safe, effective, and sustainable rotavirus vaccination program in Timor-Leste.