define antigenic drift vs antigenic shift

Understanding Antigenic Drift and Antigenic Shift: Key to Unlocking SARS-CoV-2 Variants

The ongoing COVID-19 pandemic has led to a surge in variants of concern (VoCs) flagged by the World Health Organisation (WHO), with each new variant receiving a Greek letter designation. Alpha, Beta, Gamma, Delta, and Omicron are just a few examples of these VoCs. But what exactly do we mean when we talk about viral variants? In this article, we'll delve into the world of antigenic drift and shift to understand how SARS-CoV-2 evolves and what it means for our fight against COVID-19.

What is Antigenic Drift?

Antigenic drift refers to the gradual changes in the surface proteins of a virus over time. These changes can occur due to mutations in the genetic code, resulting in slight modifications to the viral antigen. As a result, the immune system may not recognize the new variant as easily, allowing it to spread more effectively.

What is Antigenic Shift?

Antigenic shift, on the other hand, occurs when there's a sudden and significant change in the surface proteins of a virus. This can happen when two different viruses infect the same cell and exchange genetic material, resulting in a new strain with a completely altered antigen.

Understanding VoCs: The Next Generation

The World Health Organisation (WHO) flags certain variants as 'Variants of Concern' due to their increased transmissibility, virulence, or ability to evade previous immunity. With five VoCs identified so far, it's essential to understand the underlying mechanisms driving viral evolution and what we can expect from future variants.

Expert Insights

In an interview with experts from the EU-funded END-VOC project, we gain valuable insights into what drives viral evolution and what lies ahead for COVID-19. François Balloux, director of the Genetics Institute at University College London, and his colleagues Lucy van Dorp and Damien Richard share their expertise on the emergence of new variants and the importance of tracking their circulation and impact.

As we continue to navigate the ever-evolving landscape of SARS-CoV-2 variants, it's crucial that we understand the concepts of antigenic drift and shift. By grasping these fundamental principles, we can better prepare ourselves for the next generation of COVID-19 variants and work towards developing effective strategies to combat this global health crisis.

I hope you find this article informative and helpful!

Define antigenic drift vs antigenic shift