“The vaccines, which are all based on the original Chinese strain, make a good immune response that protects against this strain, so that’s good news,” he says.
While current treatments and prevention efforts don’t seem to be affected much by this change to the virus, the mutation does raise questions about how fast new strains are emerging and whether or not one of those might cause a problem in the future, Baric says.
Coronaviruses, as a group, are extremely stable. They have a special molecule -- rightly dubbed a proofreader -- that makes sure the virus gets copied correctly.
Because of this proofreader, the speed of the emergence of these new strains of the new coronavirus has been somewhat surprising to scientists who study them.
One development that Baric and other scientists are closely watching is the emergence of new strains found on mink farms in Denmark and the Netherlands that have been shown to infect humans.
There’s work being done to confirm that at least one of those strains -- the so-called cluster 5 virus -- may have evolved enough changes to its spike proteins that help it escape the vaccine.
Baric says the research needs to be verified, but early work suggests that the virus appears to have changed to help it infect minks more efficiently, while also keeping its ability to infect humans.
When a virus evolves in a way that allows it to circulate in an animal species, “it becomes more difficult to eradicate that virus,” he says.
Baric says if the virus continues to be passed in minks, if we vaccinated everyone in Denmark, but left the minks, the virus would hang out until there were enough new, susceptible hosts -- typically young children -- and then jump back into humans.
For that reason, he says mink farms may need to take further steps, like vaccinating their animals, or, in the worst case, killing their minks, to control the spread.
SOURCES:
Article: Study: New Mutation Sped Up Spread of Coronavirus
Ralph Baric, PhD, William R. Kenan Jr. distinguished professor, Department of Epidemiology, and professor, Department of Microbiology and Immunology, University of North Carolina at Chapel Hill.
Science: “SARS-CoV-2 D614G variant exhibits efficient replication ex vivo and transmission in vivo.”
Cell: “Tracking Changes in SARS-CoV-2 Spike: Evidence that D614G Increases Infectivity of the COVID19 Virus.”