Q- How effective is the COVID-19 Vaccine?

The Moderna vaccine reaches 94% effectiveness two weeks after the second dose, and the Pfizer vaccine reaches 95% effectiveness one week after the second dose.

The Pfizer-BioNTech vaccine is roughly 52% effective after the first dose, according to Pfizer data published in December 2020.

According to a document the company submitted to the FDA, the Moderna vaccine can provide 80.2% protection after one dose, compared to 95.6% after the second (in people aged 18 to 65 – it's 86.4% in those over 65).

For the Oxford-AstraZeneca vaccine, things are a bit different. In a paper published in January, the authors explain that the vaccine offers protection of 64.1% after at least one standard dose. This compares to 70.4% if you've had two full doses, or – oddly – 90% in people who have had one-half dose followed by one full dose.