coronavirus vaccine ready for use in thousands of its citizens.But while Russian President Vladimir Putin says the vaccine is “efficient” and forms a “stable immunity,” scientists around the world are expressing concerns about the lack of published data on how safe it is and how well it works.Here’s what you need to know about the Russian vaccine.The vaccine, known as Sputnik V, was developed by the Gamaleya Institute in Moscow, and the Russian business conglomerate Sistema has said it will be put into mass production by the end of the year.