A new study found that less than 1% of fully vaccinated people have experienced a breakthrough COVID-19 infection.

The Kaiser Family Foundation analyzed data from states that report breakthrough infections and found fully vaccinated Americans made up a very small portion of the infected population, with Oklahoma at 0.9% the highest and Connecticut at 0.1% the lowest.

Roughly half of the states report on breakthrough cases.

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The CDC only reports on breakthrough cases that have resulted in hospitalization or death, but the data there is even more promising.

Less than 0.004% of people who have been fully vaccinated against COVID-19 and experienced a breakthrough case needed to be hospitalized, and less than 0.001% have died from the disease. To sum up, that’s roughly 6,600 severe breakthrough cases among the 163 million fully vaccinated people in the U.S.

The numbers match previous analyses that found that between 98% and 99% of deaths were among unvaccinated people.

The study’s findings come the same day the White House announced that more than 70% of adults in the U.S. had received at least one dose of one of the vaccines. The increase in the national seven-day average comes after a spate of mask mandates returned and vaccine mandates were ordered in a number of public and private areas around the nation in an attempt to prevent a new wave of infections spurred by the delta variant.