"A growing body of evidence indicates that people fully vaccinated with an mRNA vaccine (Pfizer-BioNTech or Moderna) are less likely than unvaccinated persons to acquire SARS-CoV-2 or to transmit it to others. However, the risk for SARS-CoV-2 breakthrough infection in fully vaccinated people cannot be completely eliminated as long as there is continued community transmission of the virus."
https://www.cdc.gov/coronavirus/2019...ed-people.html
"Two studies1,2 from Israel, posted as preprints on 16 July, find that two doses of the vaccine made by pharmaceutical company Pfizer, based in New York City, and biotechnology company BioNTech, based in Mainz, Germany, are 81% effective at preventing SARS-CoV-2 infections. A
nd vaccinated people who do get infected are up to 78% less likely to spread the virus to household members than are unvaccinated people. Overall, this adds up to very high protection against transmission, say researchers."
https://www.nature.com/articles/d41586-021-02054-z
I typed the words "covid vaccinated transmission" into google and there's loads of stuff.