By Stephanie Stahl

PHILADELPHIA (CBS) — With the pause on the Johnson & Johnson vaccine, there’s renewed emphasis on the two remaining vaccines that are safe and effective. But, officials say they don’t provide 100% protection and CBS3 is learning of local cases of breakthrough infections.

These are cases where people are getting the coronavirus even though they’ve been vaccinated.

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New Jersey and Pennsylvania have not released their numbers on breakthrough cases.

Health officials say this is expected and should not be alarming in our region. Delaware is the first to provide a breakdown of its cases.

Delaware officials are tracking dozens of people who were fully vaccinated, meaning two weeks after their final shot, who then developed COVID-19 anyway.

“Just because you’re vaccinated doesn’t mean you are 100% bulletproof like any other vaccine,” Gov. John Carney said.

Delaware has more than 210,000 people who are fully vaccinated and 70 of them had breakthrough cases of COVID-19 — most cases were mild.

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“However, you do see some more serious cases, so three of our 70 breakthrough cases were hospitalized and of those three, unfortunately, one individual did pass away,” said Delaware Director of Health Dr. Karyl Rattay. “And this is predominantly occurring among elderly individuals and those with underlying conditions.”

The CDC says of the 75 million Americans who are now fully vaccinated, about 5,800 have developed COVID-19. It’s a small percentage and within the parameters of Pfizer and Moderna vaccines being 95% effective.

“Obviously this is something we take seriously and follow closely,” Dr. Anthony Fauci said. “You will see breakthrough infections in any vaccination when you’re vaccinating literally tens and tens of millions of people. So in some respects, that’s not surprising.”

The CDC says most of the breakthrough cases nationally have happened among women, it’s unclear why and most are asymptotic.

Doctors say this is more proof the vaccines work and even when they don’t, infections are less serious.

“The vast majority of people who get infected after they’ve been vaccinated either don’t have symptoms or have very mild symptoms,” Dr. John Swartzberg says.

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Philadelphia health officials say they’ve had about 53 breakthrough cases out of 500,000 people who’ve received at least one dose of the vaccine.

Stephanie Stahl