Table of Contents
What’s happening?
- After the scare cause by the XE strain of the SARS-CoV-2 virus — first reported in Mumbai earlier this month — Reports now suggest that a new sub-lineage of the Omicron variant, designated BA.2.12.1, may be behind the renewed surge in Covid cases in New Delhi.
Variant already present
- Incidentally, data uploaded from India on GISAID — a global, open access genomic database of viruses — Shows that the variant was already present in the population during the country’s last Omicron wave.
- At least 11 samples of the BA.2.12.1 lineage were collected and sequenced from India between December 2021 and February 2022, according to data available on GISAID.
- Of these nine were collected from Rajasthan, while two were from Telangana
BA.2.12.1
- 2.12.1, along with its sister lineage BA.2.12 , was reported to be behind the surge in Covid cases in the US this month.
- Now, media reports suggest that the same lineages maybe behind the increase in infections in Delhi.
- On Thursday, Delhi reported 965 new cases of Covid.
- The city’s R rose to over two this week, driving up the overall infection rate for India.
Genetic mutation
- Every living organism is run by a predefined set of genes that ‘instruct’ cells how to build proteins.
- Understanding the sequence of genes is thus like cracking the code to the organism and how it functions.
- The genetic material of the coronavirus is ribonucleic acid (RNA) strands.
- Each virus has about 26,000 to 32,000 bases or RNA “letters” in its length.
- Spike protein are the protrusions seen on the outer surface of the novel coronavirus.
- It is not clear why these variants did not dominate the Indian population during the last Omicron wave despite having higher growth advantage than the parent BA.2 variant.
- The genomic expert explained that the widespread Omicron infections at the time may have conferred immediate protective immunity to the population, preventing the spread of these variants during the early months of 2022.
So why spreading now?
- However, as anitbodies begin waning after three months, these variants may have gotten the opportunity to spread once again.
- Mutations in the L452 position of the spike protein — which is part of the receptor binding domain (RBD) — have been previously reported in a number of other variants, including Delta, Epsilon and Lambda.
- A similar mutation (at the L452 position of the spike protein), L452R, is also seen in Omicron’s BA.4 and BA.5 lineages, and is presently reportedly increasing in numbers in South Africa.
- Early estimates from data in the US suggest that the BA.2.12.1 may have significantly increased growth advantage over the parent Omicron lineage.
conclusion
- So far, there is no evidence to show that these sublineages increase the disease severity among patients.
- However, non-pharmaceutical interventions — such as wearing masks and avoiding large gatherings in closed spaces — are effective in preventing Covid irrespective of the variants.
Q) Which of the following is a water borne disease?
- Measles
- Dengue
- Yellow fever
- coli
Latest Burning Issues | Free PDF
WhatsApp