Russia claims its Sputnik V vaccine is most effective against Delta coronavirus variant

RIO DE JANEIRO, BRAZIL – The Russian Direct Investment Fund (RDIF) reported on June 15 that its Sputnik V vaccine is the most effective against the Delta variant of the coronavirus, it found after a recent scientific study.

“The Sputnik V is more effective against the Delta coronavirus variant, detected for the first time in India, than any other vaccine that has published results on this strain so far: the Gamaleya Center study submitted for publication in an international peer-reviewed journal,” RDIF tweeted, in a post in which it did not cite the scientific journal where the study was submitted.

The B.1.617 variant (Delta, according to WHO classification) is a mutation of the SARS-CoV-2 virus, which causes Covid-19. It was first detected in India in December 2020. However, this variant was reported only on March 24, after the Indian Ministry of Health said that the L452R and E484Q mutations had not been detected before December in sample analysis.

Days earlier, the World Health Organization (WHO) reclassified the three known variant subtypes detected in India 8 months ago. Only one of this family, the B.1.167.2, remains on the list of variants of international concern due to its increased transmissibility and the first indications of the need to complete vaccination schedules.

Concurrently, in the United Kingdom, where the Delta variant accounts for more than half of the SARS-CoV-2 “strains” circulating among the population, research is underway to determine whether this variant is associated with a greater capacity to cause reinfections and to induce more severe disease, in addition to being able to evade the immune system, as also pointed out by the WHO in its latest epidemiological update, according to the available scientific evidence.

The coronavirus variant detected in India may be 60% more contagious than the one found in Kent (southeast England), called Alpha, said Neil Ferguson, a leading expert at Imperial College London, last Friday. “We are receiving more data,” but “unfortunately, the news is not positive about the Delta variant,” said Ferguson, who, speaking to BBC Radio 4, said that “the best estimate at the moment is that this (Indian) variant may be 60% more contagious than the Alpha.”

The expert, whose analyses helped in the decisions taken by the Government for the March 2020 containment period, added that more data are expected in order to establish the efficacy of vaccines against the Delta variant, currently predominant in the country. Ferguson further stressed that the majority of those hospitalized in the U.K. because of the Delta variant are not vaccinated. “It is important to say that the majority of people currently hospitalized with this variant, and with any variant, are not vaccinated. So it’s clear that vaccines still have a considerable effect,” he said.

The more contagious Covid-19 variant is “poised to take hold in the region” as many European countries prepare to ease restrictions and allow more social gatherings and cross-border travel, the WHO regional director for Europe warned.

Dr. Hans Kluge explained at a press conference that the Delta variant has shown signs of eluding some vaccines and cautioned that some of the vulnerable population, especially people over 60 years of age, remain unprotected. “We’ve been here before,” Kluge highlighted. “Over the course of last summer, cases gradually increased in younger age groups and then moved to older age groups, contributing to a devastating upsurge.”

Effective vaccines against the Delta variant

In addition to the Sputnik V claims, other vaccines have demonstrated high efficacy against the new Delta variant of concern to researchers. New evidence data from actual clinical trials collected by the UK’s public health body, Public Health England (PHE), have shown that AstraZeneca’s Covid-19 vaccine offers high levels of protection against the Delta variant, formerly known as Indian, after the second dose. The results, which analyzed over 14,000 cases of the ‘Delta’ variant between April 12 and June 4, show that the two doses of Astrazeneca’s vaccine are 92% effective against hospitalizations caused by the Indian variant, with no deaths.

In this trial, the vaccine also showed a high level of efficacy against the ‘Alpha’ variant, also known as the ‘Kent’ variant, with an 86% reduction in hospitalizations and no deaths reported. The efficacy data against severe forms of the disease and hospitalizations is associated with the strong cellular (T-cell) immune response of AstraZeneca’s Covid-19 vaccine after the second dose and correlates with high and long-lasting protection.

“This evidence on real-world data shows that the AstraZeneca Covid-19 vaccine provides a high level of protection against the ‘Delta’ variant, which is currently a critical area of concern given its rapid transmission. The data show that the vaccine will continue to have a significant impact worldwide as it continues to account for the overwhelming majority of supply to India and to the Covax initiative,” said AstraZeneca’s executive vice president of biopharmaceuticals R&D, Mene Pangalos. In addition to AstraZeneca, the Pfizer-BioNTech vaccine is 96% effective against hospitalization after 2 doses, according to a study published by PHE.

Dr. Mary Ramsay, head of immunization at PHE , said that “these tremendously important findings confirm that vaccines offer significant protection against hospitalization for the Delta variant. Vaccines are the most important tool we have against Covid-19. Thousands of lives have already been saved because of them.”

She added: “It is absolutely vital to get both doses as soon as they are offered, to achieve maximum protection against all existing and emerging variants.”