As the omicron variant of SARS-CoV-2 took hold across the globe in late 2021, it became readily apparent that the pandemic had entered a new phase. Having experienced a previous COVID-19 infection or being vaccinated still left many people wondering how vulnerable they were to the virus.
Some 4.9 billion people – or 63.9% of the world’s population – have received at least one dose of the COVID-19 vaccine as of late February 2022. And more than 430 million cases of COVID-19 have been confirmed since the start of the pandemic.
So with the majority of the world population being either immunized against COVID-19 or having recovered from infection, people have rightly begun to ask: How long will the immunity triggered by either vaccination, an active infection or a combination of both provide immune protection?
This is a challenging question because the virus is relatively new and novel variants have continuously emerged. However, researchers are beginning to better understand how existing immunity protects against reinfection and the prevention of severe COVID-19 that can lead to hospitalization and death.
Read more at The Conversation.