1041:  SARS-CoV-2 virus shows little variability regardless of mutations

(Science Daily): SARS-CoV-2 mutation rate continues to below. Strain G seems to be the most widespread across Europe and Italy. The L strain from Wuhan appears to be disappearing slowly. These mutations do not seem to influence the process of developing effective vaccines.

SARS-CoV-2 has been reported to present at least six strains. Despite the mutations, the virus has demonstrated little variability, which is a positive news for the researchers working on a viable vaccine.

These results come from the most extensive study ever done on SARS-CoV-2 sequencing.

Investigators at the University of Bologna analyzed 48,635 coronavirus genomes, isolated by researchers in labs across the world. Investigators then mapped the spread and the mutations of the virus during its journey to all continents. The study was published in the journal Frontiers in Microbiology.

The first results are encouraging as they demonstrated that the coronavirus presents little variability, with about seven mutations per sample.

The variability rate of common influenza is more than double.

Federico Giorgi, a researcher at Unibo and study coordinator explained that the SARS-CoV-2 coronavirus seems optimized to affect human beings, thus explaining its low evolutionary change. This would mean that the treatments that are being developing, including a vaccine, might prove to be effective against all the virus strains.

There are six strains of coronavirus presently:

• The original -the L strain -that appeared in Wuhan in December 2019.
• Its first mutation - the S strain–that appeared at the beginning of 2020.
• Strains V and G- since mid-January 2020.

Strain G has been the most widespread till date. It mutated into strains GR and GH at the end of February 2020.

Strain G and its related strains GR and GH have been the most widespread till date, and account for74% of all gene sequences that were analyzed in the study. These strains present four mutations, two of which can change the sequence of the RNA polymerase and Spike proteins of the virus. This could possibly have a role in facilitating the spread of the virus.

Strains G and GR seem to be most widespread across Europe and Italy. GH strain appears close to non-existence in Italy, but is more widespread in France and Germany. This possibly validates the effectiveness of containment methods.

The most widespread strain in North America is GH, while GR strain occurs more frequently in South America.

In Asia, where the L strain initially appeared, the spread of G, GH and GR strains is gaining pace.

These strains came to Asia at the beginning of March, over a month after their spread in Europe.

On a global level, strains G, GH and GR are increasing. Strain S exists in some restricted areas in the US and Spain. L and V strains seem to be gradually disappearing.

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA