CDC: Less than 1% of breakthrough COVID-19 cases led to hospitalization or death

According to the latest data from the U.S. Centers for Disease Control and Prevention on breakthrough COVID-19 cases, less than 1% of people who have contracted the novel coronavirus despite being vaccinated have either been hospitalized or died. 

Though hospitalizations and deaths from COVID-19 breakthrough infections can happen in rare cases, the data highlights just how uncommon such cases are.

As of July 26, the CDC reported that 163 million Americans had been vaccinated for COVID-19. Out of those inoculations in the same timeframe, 6,587 Covid-19 breakthrough cases occurred that either resulted in hospitalization or death. 

Out of the 6,587 cases, 1,263 vaccinated people died from COVID-19, according to the CDC. About 95% of the reported breakthrough cases were hospitalizations. 

The majority of breakthrough COVID-19 cases that resulted in hospitalization or death were in elderly people, 48% of whom were women. Twenty-four percent of the breakthrough deaths were reported as asymptomatic or not related to COVID-19, according to the CDC. 

"Vaccine breakthrough cases occur in only a small percentage of vaccinated people. To date, no unexpected patterns have been identified in the case demographics or vaccine characteristics among people with reported vaccine breakthrough infections," the CDC wrote on its website.

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Vaccination rates have stalled in the U.S. despite health experts sounding the alarm over the highly transmissible delta variant that is beginning to once again overwhelm the nation’s health care system.

Health officials on Friday released details of research which was key in last week’s decision by the CDC to recommend that vaccinated people return to wearing masks indoors in parts of the U.S. where the delta variant is fueling infection surges. Researchers said the findings suggest that the CDC’s mask guidance should be expanded to include the entire country, even outside of hot spots.

The findings have the potential to upend past thinking about how the virus is spread. Previously, vaccinated people who got infected were thought to have low levels of virus and to be unlikely to pass it to others. But the new data shows that is not the case with the delta variant.

The documents were first obtained by the Washington Post, and noted that COVID-19 vaccines are still highly effective against the delta variant at preventing serious illness and death.

Meanwhile, the U.S. on Monday finally reached President Joe Biden’s goal of getting at least one COVID-19 shot into 70% of American adults — a month late and amid a fierce surge by the delta variant that is beginning to swamp hospitals and forcing authorities to reinstate various mandates aimed at curbing the spread of the disease. 

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Health officials and medical experts have expressed concern that a growing number of vaccine skeptics who refuse to get a shot will put the possibility of herd immunity at risk. 

Despite 70% of the country having at least one shot of the COVID-19 vaccine, a significant number of Americans have expressed reluctance to get the shot.

Dr. Anthony Fauci, the nation’s foremost expert on infectious diseases, estimated in April that somewhere between 70% and 85% of the U.S. population needs to get inoculated to bring this pandemic to an end.

New cases per day in the U.S. have increased sixfold over the past month to an average of nearly 80,000, a level not seen since mid-February. And deaths per day have climbed over the past two weeks from an average of 259 to 360.

Those are still well below the 3,400 deaths and a quarter-million cases per day seen during the worst of the outbreak, in January. But some places around the country are watching caseloads reach their highest levels since the pandemic began. And nearly all deaths and serious illnesses now are in unvaccinated people.

The surge has led states and cities across the U.S. to beat a retreat, just weeks after it looked as if the country was going to see a close-to-normal summer.

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Health officials in San Francisco and six other Bay Area counties announced Monday they are reinstating a requirement that everyone — vaccinated or not — wear masks in public indoor spaces.

New York Gov. Andrew Cuomo said New York City airport and transit workers will have to get vaccinated or face weekly testing. He stopped short of mandating either masks or inoculations for the general public, saying he lacks legal authority to do so.

Denver's mayor said the city will require police officers, firefighters and certain other municipal employees to get vaccinated, along with workers at schools, nursing homes, hospitals and jails.

Minnesota’s public colleges and universities will require masks indoors, regardless of vaccination status. New Jersey said workers at state-run nursing homes, psychiatric hospitals and other such institutions must get the shot or face regular testing.

North Carolina's governor ordered state employees in the agencies under his control to cover up indoors if they are not fully vaccinated.

And McDonald’s said it will require employees and customers to resume wearing masks inside some U.S. restaurants regardless of vaccination status in areas with high or substantial coronavirus transmission. The company didn’t say how many restaurants would be affected by the new mask mandate.

White House press secretary Jen Psaki said a nationwide vaccination requirement "is not on the table," but noted that employers have the right to take such a step.

The Associated Press contributed to this story.