Mutations in the S-Protein in the variants are known to be resistant to NAbs (neutralizing antibodies) resulting from either vaccinations or from natural infection. However, not all mutations behave the same. For eg the HV69-70 deletion in the Alpha does not cause effect on NAb sensitivity but increases the infectivity.
Also the deletion of the LAL242-244 in the Beta variant does not affect the sensitivity as well. Hence these variants does not pose a negative effect on the vaccines.
However, the Lambda variant (lineage C.37) in Chile and the South Americas present a different picture. In Chile where at least 60% has received a single dose, the Lambda variant is capable of escaping the immune responses induced via vaccination. 93% of the vaccines used in Chile was Sinovac.
A recent study has revealed that the insertion of RSYLTPGD246- 253N mutation in the NTD of the Lambda S-protein is associated with the increased virulence. This mutation is the cause of the rapid spread.
They say that there are two critical virological features of the Lambda variant.
Resistance to viral-induced immune responses due to the RSYLTPGD246- 253N, L452Q, and F490S mutations.
Enhancement in the rate of transmission due to the T76I and L452Q mutations.
Also the RSYLTPGD246-253N mutation overlaps with a component of the NTD “supersite” and this has enabled the Lambda variant to escape immune responses elicited by the COVID-19 vaccine.
Highlights:
Also the deletion of the LAL242-244 in the Beta variant does not affect the sensitivity as well. Hence these variants does not pose a negative effect on the vaccines.
However, the Lambda variant (lineage C.37) in Chile and the South Americas present a different picture. In Chile where at least 60% has received a single dose, the Lambda variant is capable of escaping the immune responses induced via vaccination. 93% of the vaccines used in Chile was Sinovac.
A recent study has revealed that the insertion of RSYLTPGD246- 253N mutation in the NTD of the Lambda S-protein is associated with the increased virulence. This mutation is the cause of the rapid spread.
They say that there are two critical virological features of the Lambda variant.
Resistance to viral-induced immune responses due to the RSYLTPGD246- 253N, L452Q, and F490S mutations.
Enhancement in the rate of transmission due to the T76I and L452Q mutations.
Also the RSYLTPGD246-253N mutation overlaps with a component of the NTD “supersite” and this has enabled the Lambda variant to escape immune responses elicited by the COVID-19 vaccine.
Highlights:
- Lambda S is highly infectious and T76I and L452Q are responsible for this property.
- Lambda S is more susceptible to an infection-enhancing antibody.
- RSYLTPGD246-253N, L452Q and F490S confer resistance to antiviral immunity.
Last edited:
