Getting Answers: How effective are the COVID-19 vaccines after each dose?

TUCSON (KVOA)- Pfizer-BioNTech and Moderna COVID-19 vaccines are being administered across Arizona and some viewers wanted to know the effectiveness of each dose.

The Pfizer-BioNTech COVID-19 vaccine requires two doses that are administered three weeks apart.

The vaccine is about 52% effective after the first dose and 95% effective about a week after the second dose, according to a FDA briefing document on the vaccine.

The Moderna vaccine requires two doses that are given four weeks apart.

After at least 14 days after the second dose it was 94.5% effective, according to a FDA briefing document on the vaccine.

Studies are being conducted to determine how long the effectiveness of these vaccines will last.