In a major shot in the arm for the Pfizer-BioNTech COVID-19 vaccine, researchers have reported in two studies that it is highly effective in protecting against severe COVID-19 infections caused by the variants first reported in the UK and South Africa.

In a study published in the New England Journal of Medicine on May 5, researchers analysed the prevalence of COVID-19 cases in Qatar from February 1 to March 31. Genome sequencing data from this period suggested that the B.1.1.7 and B.1.351 variants accounted for almost 95% of cases in the country.

They found that the vaccine was at least 87% effective at preventing COVID-19 due to B.1.1.7 and 72% effective at preventing COVID-19 due to B.1.351. They also reported that the vaccine could prevent severe COVID-19 caused by any of the variants with 97.4% effectiveness.

Similar, another group of researchers – this one including those affiliated with Pfizer – published a study in The Lancet based on 2.3 lakh COVID-19 infections in Israel between January 24 and April 3, 2021. In this country, the B.1.1.7 variant alone accounted for 95% of infections in this period.

Here, the researchers reported that the Pfizer-BioNTech vaccine was at least 95% effective at preventing severe COVID-19 caused by any of the variants. In the group of people who were older than 85 years and had received both doses of the vaccine, the effectiveness remained at a high, of 94%.

As of May 4, more than half of all Israelis had received both doses of the vaccine. In Qatar, 22% had received both doses and 37% had received one dose, according to data collected by the US Centres for Disease Control.

The studies offer hope that COVID-19 vaccines remain a feasible way for countries to exit the COVID-19 pandemic. They also spell good news for Pfizer, which is also planning to apply for emergency approval in the US for children aged 2-11 years to receive the vaccine.