The drug maker, Pfizer, reported today that early results of the vaccine they've been working on for COVID-19 with German partner BioNTechare are 90% effective. The vaccine, which requires two doses, had an efficacy rate higher than 90% at seven days after the second dose, meaning protection against the Coronavirus is achieved 28 days after the first dose. 43,000 volunteers were given either two doses of the vaccine or a placebo, and data found that fewer than 10% of infections were in participants who had been given the vaccine while more than 90% of the cases were in volunteers who had been given the placebo.
A 90% efficacy rate is much higher than expected if the trend continues, and The United States Food and Drug Administration has said it expects at least a 50% efficacy from any coronavirus vaccine. President Trump responded to the news today by tweeting to his 88.9 million followers: