Pfizer vaccine 97% effective in preventing symptomatic Covid-19 disease: Study

Pfizer-BioNTech's coronavirus vaccine has an efficacy of 97 per cent in preventing symptomatic disease, a study based on real-world evidence published on Thursday said. 

The study, conducted by the two pharma giants, also found that the vaccine's prevention against asymptomatic disease also stands at 94 per cent.

For the study, data from January 17 to March 6 from Israel's national vaccination campaign, has been taken. 

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It also showed the vaccine is effective against a highly transmissible Covid-19 strain first found in the UK, known as B.1.1.7. Over 80 per cent of the specimens that were part of the study were of this variant. 

However, since only a few people in Israel have been infected with the South African variant B.1.351, the vaccine's efficacy against this strain could not be found. 

"This comprehensive real-world evidence ... can be of importance to countries around the world as they advance their own vaccination campaigns one year after the World Health Organization declared COVID-19 a pandemic," Pfizer and BioNTech said in a statement as quoted by news agency AFP.

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Earlier, a similar study which was based on data from between December 20, 2020 and February 1, 2021 had shown the efficacy of 94 per cent in preventing symptomatic cases and 92 per cent in avoiding asymptomatic disease. 

Meanwhile, the UK said on Thursday that Oxford-AstraZeneca Covid-19 vaccine is "safe and effective "after Denmark suspended the jab's use. 

"We've been clear that it's both safe and effective... and when people are asked to come forward and take it, they should do so in confidence," Prime Minister Boris Johnson's official spokesman said.