Nigeria’s immunisation programme sits at the intersection of global health commitments, donor politics, and domestic policy realities. With 40 per cent of under-five deaths already linked to vaccine-preventable diseases, the country is struggling with one of the world’s highest burdens of unvaccinated children. The situation is compounded by the Global Vaccine Alliance (GAVI) recent funding shortfall, which threatens to disrupt vaccine supply before Nigeria is ready to transition to self-financing in 2028, IJEOMA NWANOSIKE reports.

The Immunisation Agenda 2030, launched by the World Health Organisation (WHO) for the decade 2021 to 2030, sets an ambitious goal: to ensure that 90 per cent of children worldwide receive essential childhood and adolescent vaccines, while halving the number of children who miss out entirely, especially in low-and middle-income countries.

While global progress remains uneven, in 2023, an estimated 14.3 million infants worldwide did not receive the first dose of the diphtheria, tetanus, and pertussis vaccine, while an additional 5.6 million were only partially vaccinated. Of the total 19.9 million zero-dose and under-immunised children, around 55 per cent lived in just ten countries. Nigeria alone accounted for about 2.3 million of these children, the highest burden globally.

The disparities were underscored in a study published in The Lancet on global vaccination coverage. The study revealed that more than half of the world’s 15.7 million zero-dose children in 2021 were concentrated in just eight countries, with Nigeria topping the list, followed by India.

It further projected that, even under optimistic scenarios, only the third dose of the DTP vaccine might achieve the 90 per cent global coverage target by 2030, highlighting the scale of the challenge.

Coverage for critical antigens remains well below the 90 per cent benchmark set by the global agenda, and the data obtained from UNICEF reported that the first dose of the DTP vaccine stands at 71 per cent, while completion with the third dose is at 67 per cent. The Guardian also learnt that coverage for measles is particularly low, with the first dose at 57 per cent and the second dose at 35 per cent. Uptake of the pneumococcal conjugate vaccine is even lower, at only 28 per cent.

Further evidence from the Multiple Indicator Cluster Survey conducted by the National Bureau of Statistics under UNICEF’s guidance shows that only 36 per cent of Nigerian children aged 12 to 23 months had received all recommended vaccines. This leaves nearly two-thirds, or 64 per cent, under-immunised.

Across the country, regional disparities are pronounced. In Sokoto State, for instance, zero-dose prevalence is as high as 50.7 per cent, while the Bauchi record stands at 35.3 per cent. In Gombe State, it is 34.4 per cent, Borno 32.3 per cent, and Kano 30.2 per cent.

Zamfara follows with 22.9 per cent. These figures reflect a North-South divide in coverage, with southern states generally faring better. Yet even in Lagos, which boasts stronger health infrastructure, local councils such as Alimosho and Ikorodu reveal troubling pockets of zero-dose prevalence, showing that urban density and infrastructure alone do not guarantee universal access.

The human consequences of these gaps are already stacked and visible. Vaccine-preventable diseases account for about 40 per cent of under-five mortality in Nigeria. Pneumonia remains the leading killer, responsible for an estimated 200,000 child deaths yearly. Measles and diphtheria outbreaks have continued to claim young lives, largely among unvaccinated children.

The Nigerian Centre for Disease Control reported 4,678 suspected and 1,397 confirmed measles cases between January and March 2025 alone. Between 2023 and 2024, the country experienced a resurgence of diphtheria, with 11,587 suspected cases, of which 7,202 were confirmed across 105 local councils in 18 states. The outbreak claimed 453 lives, the majority of whom were children between the ages of one and 14.

Sadly, The Guardian recently reported that another diphtheria outbreak, which has so far claimed the lives of 10 children in Bida Local Council of Niger State, is raising concerns over further spread of the disease, which could lead to more deaths.

The financing dimension adds another layer of concern because for two decades, Nigeria has relied heavily on external support, particularly from the Global Vaccine Alliance (GAVI), which has been central to vaccine procurement, routine immunisation campaigns, and the introduction of new vaccines. But GAVI’s most recent replenishment cycle for 2026 to 2030 fell short of its $11.9 billion target after the United States announced that it would halt all contributions to the alliance. This shortfall has raised alarm among Nigerian health experts and agencies who worry that any early reduction in GAVI support before the country’s scheduled transition to vaccine self-financing in 2028 would severely disrupt immunisation services.

UNICEF told The Guardian that any funding halt before 2028 is “worrisome,” noting that Nigeria’s immunisation programme continues to depend heavily on GAVI’s support. The agency warned that premature withdrawal could widen procurement gaps, delay the introduction of new vaccines, and further strain Nigeria’s fragile health system, particularly in efforts to reach zero-dose and underserved populations.

The agency estimated that achieving 90 per cent coverage of the third dose of DTP by 2030 could avert more than 300,000 under-five deaths in Nigeria, preventing millions of illnesses and future outbreaks.

It added, however, that these gains can only be secured if investments in primary healthcare revitalisation, workforce strengthening, and cold chain infrastructure are sustained, alongside initiatives such as the Big Catch-Up; the Routine Immunisation Intensification drive; the Zero-Dose Reduction Operational Plan, and the identify–enumerate–vaccinate strategy.

Ekiti State Commissioner for Health, Dr Oyebanji Filani, warned that the recent reduction in funds raised by the GAVI could translate to a cut in Nigeria’s allocation, potentially impacting the country’s immunisation programme.

In an interview with The Guardian, Filani noted that partners acknowledged that the resources mobilised fell short of expectations during the recently concluded Gavi meeting in Brussels. According to him, the development raises concerns about a possible decrease in the financial support Nigeria receives for vaccines.

He explained, however, that Nigeria had anticipated such challenges and, in 2017, developed a 10-year strategic routine immunisation plan. The plan committed the government to progressively increase domestic funding for vaccines, a measure Filani described as a safeguard against external funding shortfalls.

The commissioner stressed that the federal government could rely on this policy framework to fill any funding gaps that might arise from Gavi’s shortfall. He assured that state health leaders were prepared to work closely with the federal authorities to sustain immunisation coverage.

Filani further emphasised that efforts would continue to ensure that no Nigerian child is left behind, while strategies would be strengthened to reduce the number of “zero-dose” children across the country.

Still, the systemic barriers to routine immunisation go beyond financing. In an interview with The Guardian, the agency’s communication officer in Nigeria identified chronic weaknesses in the system, including inadequate funding for services, fragile last-mile logistics, shortages and poor distribution of trained health workers, and weak integration of immunisation into broader primary healthcare services.

According to him, data management challenges further limit accountability and planning. He added that geographic and security issues also remain formidable, particularly in conflict-affected northern states where armed conflict and banditry frequently prevent outreach to children. These constraints, he said, make it difficult for the country to sustain high coverage even in years when vaccines are available.

A consultant public health physician and member of the Nigerian Immunisation Technical Advisory Group (NGI-TAG), Prof. Esimai Adefunke, lamented that despite the availability of vaccines, Nigeria’s immunisation coverage remains below global targets and is driving high under-five mortality rates across the country.

Adefunke, who said that vaccine-preventable diseases are responsible for about 40 per cent of child deaths in the country, pointed out that pneumonia, as a leading killer disease, causes an estimated 200,005 deaths annually, while the measles outbreak between 2008 and 2018 led to over 153,000 confirmed cases, mostly among unvaccinated children.

“Recent diphtheria outbreaks have also claimed more than 1,200 lives, largely among unvaccinated children,” she said. The physician further highlighted that Nigeria has one of the largest populations of “zero-dose” children globally, with about 2.3 million children who have never received any vaccine.

She identified Sokoto (50.7 per cent), Bauchi (35.3 per cent), Gombe (34.4 per cent), Zamfara (22.9 per cent), Kano (30.2 per cent), and Borno (32.3 per cent) as states with the highest zero-dose burden.

Adefunke added that in Lagos, urban slums such as Alimosho and Ikorodu local councils contribute to the problem. The professor explained that immunisation remains one of the most cost-effective public health interventions, introduced to protect children from deadly vaccine-preventable diseases, emphasising that Nigeria’s current immunisation schedule, which runs from birth to 15 months, protects against illnesses such as tuberculosis, polio, hepatitis B, diphtheria, tetanus, pertussis, pneumonia, meningitis, measles, and yellow fever.

Looking ahead, the expert noted that Nigeria is preparing for life after GAVI support, expected to phase out by 2028, by implementing the National Strategy for Immunisation and Primary Health Care System Strengthening (NSIPSS).

She also added that targeting zero-dose children, improving security, and sustaining advocacy remain critical if Nigeria must reach 90 per cent coverage and reduce under-five mortality to 65 per 1,000 live births.