The Gamaleya Institute, which developed Sputnik V, said on Tuesday that the vaccine is around 90% effective against the Delta variant of the coronavirus, reported The Independent. This is slightly lower than the vaccine’s efficacy against the original strain recorded at 91.6% in phase 3 trials.

“We see that there is a slight decrease in serum activity with regard to the Delta variant – it is about 2.6 times for Sputnik V,” Denis Logunov, the deputy head of the Gamaleya Institute, was quoted by Russian news agency Tass at a press conference.

Logunov, however, claimed that other vaccines produced outside Russia had shown a bigger drop in efficacy. “We’re optimistic ... there is a fall, but the fall is insignificant,” he said.

Russian authorities have said that a recent surge in Covid-19 cases in the country is because of the reluctance of many citizens to get vaccinated as well as due to the spread of the Delta variant, which they say accounts for around 90% of all new infections, reported Reuters. Around 12% of Russia’s population is fully vaccinated so far, according to Logunov.

The Gamaleya Institute deputy chief warned that the low vaccination rate raised the risks of the virus mutating further.

Sputnik V is among the four vaccines granted restricted emergency use in India. It has been given permission for emergency use in more than 65 countries. However, the vaccine is yet to be approved by the European Union or United States’ health authorities.

On June 14, the World Health Organization had classified the Delta strain as a “variant of concern”. Four days later, the organisation’s chief scientist, Soumya Swaminathan, had said that the variant was becoming globally dominant.

Many countries around the world have reimposed restrictions in view of the spread of the Delta variant. The strain accounts for 9%-10% of total cases in France, said government spokesperson Gabriel Attal.

Multiple regions in Spain, including Catalonia, have been reporting a 20% increase in the incidence of Delta variant cases. United Kingdom Prime Minister Boris Johnson has been cautioned that its new date of easing restrictions – July 19 – was “possibly too early”.

On June 23, the European Centre for Disease Prevention and Control said that the Delta variant of Covid-19 could contribute to 90% of new cases in the European Union in the coming months.

Meanwhile, India recorded 45,951 new coronavirus cases and 817 deaths on Wednesday morning, data from the Union health ministry showed. With this, the infection tally climbed to 3,03,62,848 and the toll to 3,98,454 since the pandemic broke out in January last year.

Globally, the coronavirus disease has infected over 18.17 crore people and killed more than 39.36 lakh since the pandemic broke out in December 2019, according to Johns Hopkins University.

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