New research suggests that a new strain of the
CCP virus—called B.1.526—is spreading quickly in New York City and features mutations associated with higher viral infectivity and greater resistance to antibodies—though experts caution that more study is needed to verify the “fitness” of the mutant virus.
Variants of the
CCP virus, also known as the novel coronavirus, that were first identified in the United Kingdom, South Africa, and Brazil, have spread to multiple countries. As they spread, the variants constantly morph, with researchers looking for identifiable “spike mutations” that allow them to classify the mutant viruses into groupings, or lineages.
“The changes seen have rarely affected viral fitness and almost never affected clinical outcome, but the detailed effects of these mutations remain to be determined fully,” said the Global Initiative on Sharing All Influenza Data (GISAID), whose database was used by a Caltech research team in a study that suggests that the B.1.526 lineage may be more infectious and resistant to vaccines.
Commenting on the mutations, GISAID
said in a statement that there “may be an early indication for some potential advantage for these viruses” but that this needs to be verified and “does not necessarily mean change in clinical severity or transmission efficiency.”
Researchers from Caltech authored one of the studies, which was
published Feb. 23 in an online database and has yet to be peer-reviewed. The team identified a grouping of six distinct but closely related spike mutations that they refer to as the B.1.526 lineage.
One of the two main branches of spike mutations in this lineage, called S477N, “has been implicated to increase viral infectivity,” the researchers said. The second major branch, called E484K, is known to reduce the effectiveness of multiple types of antibodies that fight the CCP virus. A third spike mutation in the B.1.526 cluster, called D243G, has been reported as an “escape mutation” from a certain type of antibody.
The implications are that the B.1.526 lineage of coronaviruses, which was first identified in November 2020, may be both more infectious and more resistant to antibodies and vaccines. The researchers found that in February, this cluster accounted for
27 percent of all coronavirus genomes sequenced and deposited in New York City.
The second study, by researchers at Columbia University, hasn’t yet been published, but its results are broadly consistent with the Caltech study,
according to The New York Times. This study found that 12 percent of the CCP virus samples they examined had E484K, one of the two main branches of the new viral lineage.
However, according to GISAID, the detailed effects of the mutations haven’t yet been fully determined, and it’s too early to say if they mean the variants are more infectious or more resistant.
Commenting on the recent mutations, GISAID acknowledged that while “changes in the spike protein have relevance for potential effects on both host receptor as well as antibody binding with possible consequences for infectivity, transmission potential, and antibody and vaccine escape,” the actual effects would need to be confirmed by experiments.
New York City, which was the epicenter of the pandemic in the United States last spring, has recorded more than 707,000 cases of COVID-19, with a related death toll of just over 29,000.
