Vaccines rarely dominate headlines unless a crisis erupts, yet their quiet impact on public health in Pakistan has been profound. As World Immunisation Week is observed, it is worth reflecting on how one of the country’s most enduring successes continues to safeguard millions of lives. Since the launch of the Expanded Programme on Immunisation in 1978, vaccines have prevented millions of child deaths, protected mothers, and nearly eliminated paralytic polio, with a reduction of more than 99 percent since the mid-1990s. The World Health Organization estimates that routine immunisation alone averts nearly one-fifth of childhood mortality in Pakistan, a remarkable achievement by any measure.

Despite these gains, the challenge today is not simply celebrating past victories but ensuring that every child receives protection. The theme of this year’s campaign — “For every generation, vaccines work” — is a reminder that immunisation must be universal to be effective. Yet Pakistan reported over 16,000 measles cases in 2025, more than half among children who had never been vaccinated. This resurgence of a preventable disease highlights the widening immunity gap, with deadly consequences for those already weakened by poverty and malnutrition.

Children miss vaccines for many reasons: weak outreach, disrupted delivery systems, poor follow-up, or misinformation. Some, however, are “zero-dose” children who have never received a single vaccine because health services failed to reach them. This is not parental neglect but a structural failure that demands urgent correction. Pakistan’s Big Catch-Up campaign, which reached nearly three million children who had missed routine doses, demonstrated progress but also revealed the scale of the challenge. Immunisation cannot remain a reactive exercise triggered only by outbreaks; it must be embedded as a reliable public service supported by strong primary healthcare, cold chain systems, surveillance, and last-mile delivery.

The polio campaign offers lessons. Its vast infrastructure shows what political commitment can achieve, yet the persistence of polio in certain pockets underscores that the final barriers are not scientific but logistical — reaching every child consistently. Vaccine hesitancy is often blamed on ignorance, but distrust, misinformation, and unreliable services also play a role. Unless these barriers are addressed, the immunity gap will continue to widen.

Climate shocks, displacement, and rapid urbanisation further complicate immunisation efforts, particularly for children in informal settlements and disaster-hit areas. Every missed vaccine carries not only health risks but also economic costs, burdening families and straining an already fragile health system. Preventable illnesses translate into lost productivity, higher medical expenses, and setbacks in national development.

The next frontier is not more emergency drives but stronger routine systems. This requires sustained financing, protection of immunisation budgets, support for front-line workers, and investment in local delivery mechanisms. Immunisation should not be treated as an annual campaign revisited each April; it is a test of whether the state can reliably reach every child, every time. Pakistan’s health system has shown resilience in the past, but closing the immunity gap now demands renewed focus, political will, and consistent investment. Only then can vaccines truly work for every generation.