A new comprehensive study published in The Lancet has sounded a worldwide alarm: after five decades of progress, childhood vaccination coverage is stagnating or even retreating, leaving millions of children increasingly vulnerable to deadly yet preventable diseases. The analysis, released this week and drawing on 50 years of country-level data, warns that the number of “zero-dose” children—those missing even the most basic vaccines—remains distressingly high, with global immunisation efforts hampered by growing inequalities, the lasting shocks of the COVID-19 pandemic, and an upsurge in vaccine hesitancy and misinformation (Washington Post; The Lancet).
For Thailand, where decades of routine childhood vaccination have protected generations from diseases like measles, polio, and diphtheria, these new findings have profound implications for health policy, community trust, and the future stability of national public health. The underlying message is urgent: the remarkable successes of the past are at risk unless decisive action is taken, both domestically and in solidarity with the global community.
The research, led by scientists at the University of Washington’s Institute for Health Metrics and Evaluation and funded by the Bill & Melinda Gates Foundation and Gavi, the Vaccine Alliance, finds that more than 4 billion children worldwide have been immunised since 1974—contributing to at least 154 million lives saved. However, progress has plateaued, particularly in recent decades. According to The Lancet analysis, global coverage for core vaccines targeting illnesses such as measles, polio, tuberculosis, diphtheria, tetanus, and pertussis (DTP) nearly doubled between 1980 and 2023. Yet, after 2010, advances slowed dramatically, and in some regions, coverage has even reversed since the onset of the coronavirus pandemic (CIDRAP; STAT News).
A critical concern emerging from the study is the persistent gap in access to vaccines between different regions and socio-economic groups. Though routine childhood vaccines remain among the most powerful and cost-effective public health interventions, millions of children—especially those in low- and middle-income countries—continue to be missed. The World Health Organization estimates that in 2023 alone, 14.5 million children received no vaccines whatsoever (WHO Immunization Coverage Factsheet). The majority of these zero-dose children are concentrated in sub-Saharan Africa but also remain a concern in pockets of Southeast Asia and elsewhere.
Senior study author from the University of Washington’s Institute for Health Metrics and Evaluation commented in a statement: “Despite the monumental efforts of the past 50 years, progress has been far from universal. Large numbers of children remain under- and un-vaccinated. Routine childhood vaccinations are among the most powerful and cost-effective public health interventions available, but persistent global inequalities, challenges from the COVID pandemic, and the growth of vaccine misinformation and hesitancy have all contributed to faltering immunisation progress” (Washington Post).
In both wealthy and less affluent countries, the study finds that vaccine coverage has plateaued or dropped for key antigens. In 21 of 36 high-income countries, at least one vaccine saw a decline in coverage between 2010 and 2023. The coronavirus pandemic made things dramatically worse: school closures, overwhelmed health systems, and disrupted supply chains led to tens of millions of children missing their routine shots. By 2023, vaccination rates for critical diseases had still not returned to pre-pandemic levels. This shortfall has already resulted in disease outbreaks, as seen in the measles surges reported in Africa, Europe, and the United States (France24; STAT News).
Kate O’Brien, WHO director for immunisation, vaccines and biologicals, echoed these worries in an official statement: “Despite incredible progress brought about by vaccines, we are now confronting a painful reality: Progress has stalled and in some countries is being lost. Immunisation rates have plateaued, and year after year, we are reaching the same proportion of children without extending their reach to those left behind. Unless we intensify efforts to reach more children, increase domestic investment, and strengthen vaccine confidence and demand, we risk undoing years of hard-won progress—leading to a future where more children suffer from preventable illnesses and premature death” (Washington Post).
Vaccine hesitancy—a delay in acceptance or refusal of vaccines despite availability—has only grown in the digital age, often fuelled by misinformation or social media “echo chambers”. The phenomenon is not new but has taken on renewed urgency in recent years, with WHO designating it as one of the top ten global health threats even before COVID-19 (Wikipedia: Childhood vaccination). The consequences are immediate and deadly: when communities forgo vaccines, diseases once thought to be controlled can quickly surge back. The 2023 outbreak of civil war in Sudan, for example, led to a collapse in the number of children receiving DTP vaccines, dropping coverage from nearly 90 percent to about half, according to the new study. Elsewhere, planned budget cuts to vaccines, especially in resource-constrained settings, are likely to aggravate these inequities, while high-income nations face rising costs as outbreaks become more frequent.
In the United States, political controversies and mixed public messaging have reportedly weakened longstanding confidence in vaccination. Recently, national policy reversals relating to WHO funding and immunisation support have triggered further debates about the role of evidence-based guidance and the dangers of misinformation. Sir Andrew Pollard, director of the Oxford Vaccine Group, called these trends a “worrying” sign and accused certain governments of “undermining” vaccine confidence, risking further drops in coverage worldwide (Washington Post).
These global developments have a direct bearing on Thailand’s own health landscape. Thailand has historically achieved high rates of coverage for childhood immunizations thanks to strong public health infrastructure, leadership from the Ministry of Public Health, and community trust in health officials. The country has succeeded in eradicating polio and dramatically reducing measles cases through sustained vaccination drives. Yet, experts warn that Thailand cannot afford complacency. The nation’s experience with sporadic outbreaks—such as the 2022 measles cases in border provinces—demonstrates that gaps in immunisation, especially among migrant or stateless populations, can quickly lead to wider flareups and threaten the health security of the entire population (WHO Thailand).
Leading Thai epidemiologists at the Ministry of Public Health urge policy-makers and community leaders to redouble efforts in targeted outreach and education, particularly in remote areas and urban slums where vaccine coverage can lag. The example of Thailand’s school-based vaccination campaigns and its robust maternal-child health network highlights the importance of sustained investment and innovative approaches—such as mobile clinics for hard-to-reach communities or collaborations with Buddhist monastic institutions to boost local trust.
The Thai context also reveals specific challenges: a steady stream of cross-border migration, the presence of undocumented populations who may slip through routine health screenings, and occasional outbreaks of misinformation around vaccines, especially online. The importance of inclusive, language-accessible public health messaging cannot be overstated. Community health volunteers remain a vital bridge between local populations and health authorities, delivering not just vaccines but reassurance and reliable information—a strategy increasingly recommended worldwide (Lancet Global Burden of Disease Study).
From a wider cultural and historical perspective, Thailand’s deep-rooted respect for medical authority and community elders has supported high vaccine uptake for most of the past four decades. Because Buddhism generally encourages compassion and evidence-based practices that prevent suffering, temple-based health campaigns have successfully promoted acceptance of immunization as both a scientific and a moral good. However, even in Thailand, sporadic anti-vaccination rhetoric occasionally takes hold, especially in online spaces. A 2022 study published in Vaccine identified both complacency and convenience barriers among some middle-class urban parents, illustrating that sustained engagement is necessary at all social levels (PubMed: Vaccine hesitancy Thailand).
The global projection is worrisome: unless urgent corrective measures are adopted, the number of “zero-dose” children worldwide is expected to remain high through 2030. Epidemiologists caution that the world is at risk of reversing decades of gains, as new generations grow up without protection from diseases long kept at bay. Universal immunisation, say experts, will only be realised by closing both the access gap for the marginalised and the confidence gap for the hesitant.
In practical terms, what should Thailand and its residents do? The evidence advocates for continuing robust investment in the national immunisation program, ensuring that vaccines are free and widely available—not just in cities but in every rural village and border area. Schools, temples, and community organizations must be empowered as trusted messengers, countering rumours with facts and compassion. Policymakers are called to maintain high levels of funding and vigilance, especially as global health partners may face budget pressures. Families and guardians are advised to check children’s vaccination cards and consult health authorities if in doubt—remembering that timely vaccination is both an individual right and a collective responsibility.
For the Thai public and health workforce, the message is clear: vigilance and proactivity are the best defences against a dangerous return of vaccine-preventable diseases. Sharing accurate information, supporting friends and neighbours to access vaccines, and challenging misinformation when encountered—both online and in person—are concrete actions every Thai can take today to protect the nation’s health.
This new research serves as a vital wake-up call: Immunisation is a success to be cherished and defended. The world, including Thailand, is at a pivotal crossroads, where choices made today will shape the lives of millions of children tomorrow. Responsible action, informed by science and rooted in Thailand’s tradition of communal care, must guide national and local efforts. Only through such sustained commitment will future generations be shielded from the pain and tragedy of preventable illness.