September 30, 2022

Medical Trend

Medical News and Medical Resources

Neutralizing activity against Indian second-generation mutant strains

Neutralizing activity against Indian second-generation mutant strains

 

 

Neutralizing activity against Indian second-generation mutant strains.  On May 27, 2021, a pre-printed article uploaded by the French Pasteur’s bioRxiv reported some molecular virological characteristics of the second-generation Indian mutant strain B.1.617.2.

NTD and RBD of B.1.617.2 contain multiple mutations, and B.1.617.2 is believed to spread faster than other mutants.

This study isolated infectious B.1.617.2 from a traveler returning from India.

Compared with other mutant strains, B.1.617.2 has escapes to some neutralizing antibodies against NTD and anti-RBD epitopes, including Eli Lilly’s Bamlanivimab.

Compared with B.1.1.7, the sera of recovered patients and Pfizer’s mRNA vaccine BNT162b2 had 3 to 6 times lower neutralizing activity to B.1.617.2. The serum that received a dose of AstraZeneca vaccine AZD1222 could hardly inhibit B.1.617.2.

Therefore, the spread of B.1.617.2 is related to the escape of antibodies against the S protein epitope.

Neutralizing activity against Indian second-generation mutant strains. 


How protective are the existing vaccines against other mutant strains?

The Institute of Health Metrics and Evaluation (IHME) in Seattle, the United States is one of the most well-known modeling agencies. The modeling of existing vaccines at IHME shows that:

Neutralizing activity against Indian second-generation mutant strains. 

For virus strains containing the E484K/Q mutation, including the South African mutant B.1.351, Brazil mutant P.1, and India mutant B.1.617; the model showed that the 7 vaccines are all protective against symptomatic COVID-19 decline. Among them are Pfizer -76%, Moderna-79%, AstraZeneca -10% (real data), Johnson & Johnson -64% (real data), Satellite V -70%, Novavax-49% (real data), Xing-38%, Sinopharm-55%.

But for the virus strains that do not contain the E484K/Q mutation, these seven vaccines have more than 50% protection against symptomatic COVID-19. Of course, this is the basis for obtaining approval for marketing.

 

 

 

(source:internet, reference only)


Disclaimer of medicaltrend.org