Nose sprays, patches and durable immunity: The next generation of COVID-19 vaccines

The past 20 months has seen an explosion of vaccine development, with COVID-19 vaccine testing and rollout happening at an unprecedented pace in the face of a global pandemic.

There have been absolute triumphs – the fact we have multiple safe, effective vaccines is remarkable – but there have also been challenges.

We’ve seen storage and delivery issues, vaccine hesitancy, breakthrough infections and the beginnings of waning immunity.

Vaccine innovators around the world have these challenges in their sights. They are