By Staff

BOSTON (CBS) — A very small percentage of people in Massachusetts who have been fully vaccinated against the coronavirus still tested positive for COVID, according to new “breakthrough” case data from the Department of Public Health.

The department said that as of May 24th, there were 3,343 people in Massachusetts who have been fully vaccinated and then tested positive for COVID.

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“This total number represents 0.11% of all fully vaccinated people (2,949,248) in MA as of that date,” the department said.

Breakthrough infections are defined by the Centers for Disease Control as positive tests that occur more than two weeks after a person has received their second vaccine dose, or one dose of a single-shot vaccine. CDC data shows just under 2,500 breakthrough cases nationwide that caused hospitalization or death.

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“Vaccine breakthrough cases are expected,” the CDC says on its website. “COVID-19 vaccines are effective and are a critical tool to bring the pandemic under control. However, no vaccines are 100% effective at preventing illness in vaccinated people. There will be a small percentage of fully vaccinated people who still get sick, are hospitalized, or die from COVID-19.

The CDC adds that there’s evidence that vaccines make illness less severe for vaccinated people who still get sick from COVID.

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