Abstract

COVID-19 has changed everyone’s lives. At one time or another, most of us have had to stay at home and socially distance ourselves from others. But in some countries, people are starting to get out of lockdowns. 

The last lockdown in England started in January 2021. Relaxing the restrictions afterwards happened gradually. It depended mainly on the number of immune people. Was this a good strategy? We created a mathematical model to see if lifting the restrictions was well timed. The strategy was successful at first. But the emergence of the Delta variant changed things. Our model shows that vaccination alone may not be enough to stop another peak of hospitalisations and deaths.