Viruses accumulate mutations as they replicate in infected cells. Repeated replication can lead to viral strains that show attenuated virulence. Such strains may act as vaccines if the attenuated virus can produce immunity without serious disease.
This approach is not new. Albert Sabin developed an attenuated poliovirus vaccine in the mid-20th century that helped eradicate naturally occurring polio in the Western Hemisphere. Attenuated viral vaccines for rubella, measles, yellow fever and other diseases are widely used.
Can a similar vaccine be developed for COVID-19?
Researchers at the University of Alabama at Birmingham have published a foundational study for that possibility in the Journal of Virology. They asked a simple question: Which mutations predominate when the SARS-CoV-2 virus that causes COVID-19 is grown in successive generations — called passages by virologists — in…