Skip to main content


The COVID-19 delta variant: FAQ addresses transmission, vaccine effectiveness

July 15, 2021 9004

The COVID-19 delta variant, originally identified in India and shown to be 40% to 60% more contagious than previous variants of the coronavirus, is now the most common variant in California. It’s also on track to become the dominant variant globally.

Because the delta variant is more transmissible, scientists are especially concerned as large populations of people remain unvaccinated throughout the U.S. and the world.

Yet the data show that the COVID-19 vaccines are safe and effective and save lives. Two doses of an mRNA vaccine ― currently the Pfizer-BioNTech and Moderna vaccines ― provide 88% protection against the delta strain, according to a study.

Information on delta variant added to COVID-19 Vaccine Information Toolkit

CDA on July 14 published frequently asked questions about the delta variant, including its transmissibility, how it impacts fully vaccinated individuals or individuals with natural immunity, the effectiveness of the COVID-19 vaccines against the delta variant and the potential future need for boosters.

Find the FAQ in CDA’s COVID-19 Vaccine Information Toolkit. Released in January, the toolkit also includes resources to help dentists promote vaccine confidence in the office, conduct vaccine administration training and more.

Comments are only visible to subscribers.