Ben Krishna, Postdoctoral Researcher, Immunology and Virology, University of CambridgeIt is controversial whether viruses are alive, but – like all living things – they do evolve. This fact has become abundantly clear during the pandemic, asSome of these variants have been better at spreading from person to person, eventually becoming dominant as they out-compete slower versions of SARS-CoV-2, the virus that causes COVID-19.
The virus cannot, however, improve indefinitely. The laws of biochemistry mean that the virus will eventually evolve a spike protein that binds to ACE2 as strongly as possible. By that point, the ability of SARS-CoV-2 to spread between people will not be limited by how well the virus can stick to the outside of cells.
that improve the spike protein’s ability to bind to human cells that omicron doesn’t have. Besides this, improvements could be made to other aspects of the virus life cycle, such as genome replication, as I mentioned above.But let’s assume for a second that omicron is the variant with maximised spreading ability. Perhaps omicron won’t get any better because it is limited by genetic probability.