Beyond the national average: closing measles and equity gaps in Timor-Leste’s childhood immunization policy

A policy analysis of three Demographic and Health Surveys, 2009–10 to 2025–26

By: Mariano da Silva Marques, MD, MPHM

Doctoral Program In Public Health, Faculty of Medicine, Universitas Sebelas Maret, Indonesia

Key messages

After 16 years and three national surveys, only approximately half of the children aged 12–23 months had received all basic vaccinations: 52.6% in 2009–10 and 52.3% in 2025–26.

• Coverage of the first dose of measles-containing vaccine (MCV1) fell from 69.3% in 2016 to 63.9% in 2025–26, far below the 95% two-dose coverage recommended to prevent measles transmission.
• Wealth-related gaps in DTP3 and MCV1 coverage narrowed sharply, but for measles, this was mainly because coverage fell among better-off children, not because the poorest children caught up.
• Children of mothers with no education remain the furthest behind; their MCV1 coverage is 50.2% in 2025–26, compared with 67.7% among children of mothers with secondary education.
• The National Immunization Strategy 2026–2030 should prioritize measles–rubella recovery, set equity targets for individual antigens, and use individual-level records to track dropouts and zero-dose children.

The policy problem

Timor-Leste has much to offer. Since the Expanded Program on Immunization began in 2002, the country has expanded its schedule from six to thirteen antigens and eliminated maternal and neonatal tetanus (2012), measles (2018), and rubella (2023) [5]. Pneumococcal conjugate and human papillomavirus vaccines were introduced in 2024 [8]. These achievements demonstrate what the program can deliver when political commitment, partner support, and service delivery are aligned.

Yet, routine coverage of the core childhood schedule has not improved in more than a decade. The Ministry of Health is now preparing a costed National Immunization Strategy (NIS) for 2026–2030, at a time when the global partner landscape has shifted and the funding available for immunization has fallen [6,7]. Decisions on where to direct limited resources will depend heavily on how progress is measured. If the national average or a single composite indicator is the main yardstick, the most important problems may remain hidden.

This article uses published estimates for children aged 12–23 months from the 2009–10, 2016, and preliminary 2025–26 Demographic and Health Surveys (DHS) [1–3], analyzed in an accompanying study [4], to identify three policy problems: stagnant full coverage, declining measles vaccination, and inequalities that national and composite indicators can mask. It then sets out options for NIS 2026–2030.

What the evidence shows

Full coverage has stalled

Coverage of all basic vaccinations was 52.6% in 2009–10, 48.7% in 2016, and 52.3% in 2025–26 [1–4]. The 3.6 percentage-point (pp) increase since 2016 looks like progress only when 2016 is used as the baseline; against 2009–10, the country is where it started. Children are increasingly reaching services—BCG coverage rose from 76.7% to 83.8% and DTP1 coverage from 75.1% to 79.8%—but many do not complete the vaccination schedule. Dropout between the first and third DTP doses exceeded 10% in every round (11.6% in 2009–10, 21.3% in 2016, and 14.5% in 2025–26), and the third dose of oral polio vaccine (OPV3) remained the weakest component at 60.1%. Approximately one in five children (20.2%) had not received DTP1 in 2025–26 (down slightly from 24.9% in 2009–10 and 21.6% in 2016), an indicator closely related to the zero-dose measure used by the Immunization Agenda 2030 [14].

Measles vaccination is a warning signal

MCV1 coverage in 2025–26 (63.9%) was the lowest of the three rounds, falling from 67.8% in 2009–10 and 69.3% in 2016 [1–4]. The decline was concentrated among better-off and urban children: coverage in the highest wealth quintile fell from 78.2% to 66.5%, and in urban areas from 74.2% to 61.7% between 2016 and 2025–26. A national serosurvey has already identified measles immunity gaps and a high potential for outbreaks among children and young adults [11]. Because measles is highly transmissible, it is usually the first vaccine-preventable disease to return when coverage falls; the decline therefore puts the country’s elimination status at risk.

A narrower gap is not the same as equitable progress

The wealth slope index of inequality (SII) fell from 29.4 to 7.9 pp for DTP3 and from 31.0 to 8.1 pp for MCV1 between 2016 and 2025–26 [4]. For DTP3, part of this was genuine progress: coverage in the poorest quintile rose from 48.1% to 60.5%, while the richest quintile moved slightly from 72.4% to 68.5%. For MCV1, however, coverage in the poorest quintile changed little (54.4% to 58.4%), and the gap closed mainly because the three wealthiest quintiles declined. A policy that celebrated the narrower gap would be rewarding lower coverage overall.

Other inequalities also persisted. Children of mothers with secondary education had coverage 9–18 pp higher than children of mothers with no education in every round and for every antigen examined (for MCV1 in 2025–26, 67.7% versus 50.2%), and 29.8% of children of mothers with no education had not received DTP1 in 2025–26 [3,4]. The urban advantage seen in earlier rounds disappeared, consistent with the service organization and communication barriers documented in Dili [12] and the missed opportunities for vaccination observed among 41% of eligible children attending health facilities [13]. Across 12 municipalities, the range of basic coverage remained approximately 36 pp in all three surveys, although municipal estimates were too imprecise to rank individual units [4].

What gets measured shapes policy

Equity monitoring commonly relies on a composite indicator, such as receipt of all basic vaccinations [15,16]. However, a composite indicator cannot exceed the coverage of its weakest component. In 2009–10, low OPV3 coverage in the richest quintile (47.2%) made basic coverage appear almost equal across wealth groups (a gap of 2.0 pp), even though the DTP3 and MCV1 gaps were 17.7 and 21.0 pp [4]. Similarly, in 2025–26, the highest-minus-lowest wealth gap for all basic vaccinations was just 1.4 pp (SII: 3.0 pp) because OPV3 coverage in the richest quintile (55.3%) lagged behind middle wealth groups [3,4]. A dashboard limited to ‘fully vaccinated’ children would conclude that there is little wealth inequality to address.

Summary of key survey trends (2009–10 to 2025–26)

Across the 16-year period spanning the 2009–10, 2016, and preliminary 2025–26 DHS rounds, national basic vaccination coverage among children aged 12–23 months remained essentially unchanged at 52.6%, 48.7%, and 52.3%, respectively [1–4]. While service initiation improved, with BCG rising from 76.7% to 83.8%, DTP1 increasing from 75.1% to 79.8%, and DTP1 non-receipt declining from 24.9% to 20.2%, completion of the multi-dose series lagged. DTP3 reached 68.2% and OPV3 reached 60.1%, respectively, in 2025–26, with DTP1-to-DTP3 dropout remaining high at 14.5% (compared with 11.6% in 2009–10 and 21.3% in 2016). Meanwhile, MCV1 dropped by 5.4 pp between 2016 (69.3%) and 2025–26 (63.9%), driven by declines among urban children (74.2% to 61.7%) and the richest wealth quintile (78.2% to 66.5%). Although the wealth slope index of inequality narrowed from 29.4 to 7.9 pp for DTP3 and from 31.0 to 8.1 pp for MCV1 between 2016 and 2025–26, steep educational disparities endured: children of mothers with secondary education consistently achieved higher coverage than those of mothers with no education across all antigens, including a 17.5 pp advantage in MCV1 (67.7% vs. 50.2%) and a 15.9 pp advantage in DTP3 (71.6% vs. 55.7%) in 2025–26 [1–4].

Policy context

Several developments have created an opening for change. The Ministry of Health, with the World Health Organization (WHO), UNICEF, Gavi, the Vaccine Alliance, and other partners, began developing the costed NIS 2026–2030 in mid-2025 [6,7]. The 2024 joint review of the Expanded Programme on Immunization recommended incorporating dropout tracking and follow-up mechanisms into routine immunization [8]. In 2026, the Ministry began piloting an Immunization e-Tracker in Dili, the country’s first individual-level digital immunization record [9]. The government’s share of vaccine financing rose from 64% to 80% between 2022 and 2023 [10], and public health services are free for Timorese nationals [11].

These are important foundations, but they do not by themselves determine whether the gaps described above will close. This depends on the targets the NIS sets, the indicators it monitors, and the populations it prioritizes.

Policy recommendations

Recommendation 1: Make measles–rubella recovery the first operational priority

The Ministry of Health should conduct a rapid review of measles–rubella vaccination using immunization registers, vaccine stock data, and surveillance data, with particular attention to Dili and other urban areas and groups in which coverage declined. Catch-up should be delivered through periodic intensification of routine immunization and, where immunity data justify it, a follow-up campaign. Case-based surveillance also needs strengthening; only 38% of measles–rubella IgM results were returned within four days [10].

Recommendation 2: Build equity into NIS targets and monitoring

NIS should set targets for individual antigens (DTP3, OPV3, MCV1, and the second measles dose) in addition to the composite indicator. Annual equity reports should present coverage by wealth quintile, maternal education, residence, and municipality, together with summary measures such as the SII and their uncertainty [15]. Every gap should be read alongside the coverage level of the worst-off group, so that a gap that narrows because better-off children lose coverage is not reported as success. DTP1 non-receipt and zero-dose children should be tracked in line with the Immunization Agenda 2030 [14].

Recommendation 3: Reach children of mothers with no education and the poorest households

Microplanning should identify communities with high concentrations of unvaccinated children and schedule regular outreach and mobile sessions to address this issue. Caregiver communication should explain the full schedule, timing of the next visit, and the importance of completing all doses. Every contact with the health system, including sick child visits, growth monitoring, and antenatal and postnatal care, should include a check of vaccination status to reduce missed opportunities [13].

Recommendation 4: Reduce dropout through individual-level tracking

Dropout of more than 10% in every survey round shows that completion, not only initiation, requires attention [17]. The e-Tracker should be scaled beyond Dili as quickly as data quality and staffing allow, with automatic defaulter lists, follow-up by health workers and community volunteers, and reminders to caregivers. Health worker guidance should address practices that lower polio coverage, such as withholding oral polio vaccine during diarrheal illness, which was reported in 2009–10 [1].

Recommendation 5: Redesign urban immunization services

The loss of urban advantage calls for a specific urban strategy. Studies in Dili have documented irregular vaccination sessions, incomplete communication with caregivers, and competing caregiver obligations [12]. Predictable session schedules, extended or weekend hours, and integration with private and non-governmental providers could make services easier to use for working parents.

Recommendation 6: Strengthen the evidence base

The final 2025–26 DHS report should publish sampling errors, and the survey microdata should be released promptly so that changes in inequality can be tested formally. Survey and administrative coverage estimates should be reconciled each year. Home-based record retention, which rose to approximately 70% in 2025–26 [3,4], should continue to be promoted because it improves both service delivery and measurement.

Implementation considerations

These recommendations involve trade-offs. Campaigns can quickly raise measles immunity but divert staff from routine services; they should complement, not replace, stronger routine immunization. Outreach to remote and disadvantaged communities costs more per child than fixed-site services; therefore, the costed NIS must include operational budgets for transport, per diems, and cold chain, not only vaccine procurement. With external funding contracting [6], sustaining the recent rise in domestic financing will be essential.

The health workforce is a binding constraint. The national Immunization in Practice training rolled out in 2025, the first in nearly two decades, responded to reports that health centers lack enough skilled staff in vaccination [5]. Digital tracking will add to workloads unless it replaces, rather than duplicates, paper registers. Finally, equity reporting is only useful if it is used: municipal health services should review disaggregated data in regular performance meetings and be accountable for the coverage of their most disadvantaged children.

Limitations of the evidence

The 2025–26 estimates are preliminary and may be revised. Standard errors were not published for most estimates; therefore, changes smaller than about 5 pp nationally and much larger differences between municipalities cannot be distinguished from sampling variation [4]. Vaccination status relied partly on maternal recall, and the proportion of children with a record seen rose between rounds. Coverage does not equal immunity [11]. These limitations argue for caution about precise figures but not about the overall direction of the findings, which is consistent across indicators.​

Conclusion

Timor-Leste’s national immunization averages conceal a program that has stalled at approximately half of children fully vaccinated, a decline in measles vaccination that threatens elimination, and inequalities that composite indicators can hide. The NIS 2026–2030 is an opportunity to correct the course. Prioritizing measles–rubella recovery, monitoring equity by individual antigen, reaching the children of the least-educated mothers and poorest households, and tracking every child through individual records would help ensure that the next survey shows progress for all children, not only a narrower gap.

References

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