MOSCOW (BLOOMBERG, REUTERS) - An analysis of the 3.8 million Russians who received both Sputnik V shots between December and March showed that the vaccine has 97.6 per cent efficacy, the inoculation's state-run developers said in a statement on Monday (April 19).

The data, which compare the infection rate of people who received the shots with the incidence among the unvaccinated population, will be published in a peer-reviewed journal in May, according to the Russian Direct Investment Fund and Gamaleya National Research Centre.

The new effectiveness rate is higher than the 91.6 per cent rate outlined in results from a large-scale trial of Sputnik V and published in The Lancet medical journal earlier this year.

Using a database of people who received both doses of the vaccine, scientists at Moscow's Gamaleya Institute, which developed it, calculated a real-world effectiveness rate of 97.6 per cent, according to Russian scientist Denis Logunov, a lead developer of the Sputnik V coronavirus vaccine, during a presentation for the Russian Academy of Sciences.

The high efficacy will be welcomed by the World Health Organization (WHO), which is working "very intensely" with Russian and Chinese authorities to get their vaccines pre-qualified, director Hans Kluge said in Belgrade after a meeting with Serbia's health minister.

"In order to get out of the pandemic, we need to accelerate vaccination. We need to increase the production capacity and to expand the portfolio of vaccines," Mr Kluge said.