India has recorded over two lakh COVID-19 cases in the last 24 hours, its highest ever tally since the outbreak of the coronavirus pandemic.
While reports of non availability of hospital beds, scare supply of oxygen cylinders and vaccination drives being halted due to shortage of vaccines are pouring in from different parts of the country, grim images of patients lying in ambulances and pyres going up in flames are reiterating all over again as to why the pandemic cannot be taken lightly.
But what is triggering this massive surge? Is the new ‘double mutant variant’ to blame for his unabated rise in the number of cases?
The National Institute of Virology (NIV) shared limited data last week during a meeting with district laboratories in Maharashtra detailing a break-up of 361 genome-sequenced samples that were collected between January and March this year.
The presence of a double mutation was detected in 220 of the 361 samples — almost 61 per cent. This double variant has now been formally classified as B.1.617 variant.
The B.1.617 Variant
The B.1.617 variant of SARS-CoV-2 has two mutations – E484Q and L452R. While both are separately found in many other variants of the coronavirus, India for the first time has reported them together.
The two mutations are essentially found in spike protein of the coronavirus. The spike protein helps the coronavirus to bind itself to human cell’s receptors and secure easy entry into a host cell.
The E484Q mutation is similar to E484K, a mutation found in the United Kingdom and South Africa variants of the coronavirus.
The L452R mutation has been found in rapidly spreading coronavirus variants in California in the United States and increase binding power of spike proteins with ACE2 receptors on human cells, thereby making it more easily transmissible. Experts say L452R also has the ability to potentially enhance viral replication.
Together, E484Q and L452R are more infectious, and can evade antibodies.
Viruses mutate by nature and experts estimate that nearly 5,000 mutant variants have been discovered already since India started sequencing coronavirus mutations.
While studies are being conducted to understand if the viruses are evading the vaccines, double mutant variants – originally found in Maharashtra – are now being reported from a few other states as well.