Protection against Covid-19 increases over 6 months after vaccination with Sputnik V - RDIF

Interfax, 26.08.2021

MOSCOW. Aug 26 (Interfax) - The results of the research conducted in Argentina showed a gradual increase of protection against Covid-19 over a six-month period after receiving the Russian Sputnik V Covid-19 vaccine, the Russian Direct Investment Fund (RDIF) said on Wednesday.

"Our observations suggest that protection increases over 6 months following vaccination as a consequence of antibody maturation, resulting in improved potency of antibodies to viral escape mutations," according to the research conclusions published on the vaccine's Twitter account.

According to the study results summarized in an article published in medRxiv, the preprint server for health sciences, a significant increase in the neutralizing potency index was observed at 120 days compared with the values observed at 42 days after vaccination.

The study was carried out by a group of scientists from a large number of universities and medical establishments of Argentina, including the University of Buenos Aires, as well as Washington University in St. Louis, the U.S., examined a collection of 1,800 serum samples obtained between January and August 2021 was used. The authors of the study examined the longitudinal antibody responses and viral neutralizing capacity to the Alpha, Beta, Gamma, and Delta variants, designated by the World Health Organization as variants of concern, and the Lambda strain, which is a variant of interest.

The analysis indicates that while anti-spike IgG levels significantly wane over time, their neutralizing potency increases, especially for the Beta and Gamma variants, which showed the highest propensity for "neutralization escape", the ability to escape being detected by a patient's immune system, according to the article's preprint.

A number of other studies conducted earlier also showed similar results, indicating a gradual increase in neutralizing antibody potency in convalescent Covid-19 patients, the scientists said.