Russia was the first country to register a COVID-19 vaccine, with its health ministry giving emergency approval to the Sputnik V vaccine in August 2020.

This decision was met with scepticism from the international scientific community because it came a month before the results of phase 1 and 2 trials were published.

Growing data from clinical trials and real world rollouts suggests the vaccine is safe and very effective.

But there are several outstanding questions around the vaccine, such as whether it’s associated with the very rare blood clotting condition seen with AstraZeneca’s vaccine, and how well it performs against variants of the coronavirus.