Health care systems everywhere scrambled to respond to covid-19—it would be a waste if the new infrastructure isn’t kept running to handle other health needs, by way of a preventative, global adult-vaccination programme.

This could provide immunological coverage to soften the blow of future pandemics and address other disorders, from HIV and tuberculosis to obesity and heart disease.

Covid-19 has cost millions of lives and exposed weaknesses in public health care. We have a moral responsibility to learn from it, act and save others.

The pandemic has accelerated advances in vaccine development, manufacturing and delivery, as well as the build-out of technology systems, health centres and trained staff.

We can leverage this to initiate a vaccination campaign to fight infectious diseases and develop population-level immunity against respiratory diseases like influenza and pneumonia.

This could go beyond the traditional definition of a vaccine and include preventative and therapeutic injectables for HIV, cholesterol and blood-pressure management, contraception and other conditions.

As for the tools themselves, there is good news. Vaccine technology has progressed dramatically, in a revolution that began well before covid-19. Methods such as using RNA and adenovirus have made it much easier to develop new vaccines, and the evolution of adjuvants such as ASO1 (used in tuberculosis vaccines) and lipid nanoparticles mean that a new generation of tools will soon be available to tackle many of the most dangerous pathogens in the world.

For example, an annual injection of a medication based on small interfering RNA (siRNA) technology, called inclisiran, could reduce cholesterol. Similar siRNA compounds might be used to manage hypertension with an annual injection.

There are other long-acting, preventative injectable drugs, such as cabotegravir for HIV, and injectable birth control such as Depo-Provera. These interventions are preventative; equivalent to vaccines. They could be delivered by the same infrastructure as for covid-19.

Developing a global adult-vaccination programme out of the infrastructure built for covid-19 would be as profound a legacy for public health as the creation of the United Nations out of the ruins of the second world war was for international relations. It can prevent early death in millions of people each year and give better quality of life to many millions more, fueling stronger economies and societies. The world can emerge stronger and healthier for a relatively modest investment, provided we don’t waste this moment.