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  • So-called “breakthrough infections” have been reported in some people who have been fully vaccinated.
  • But raw data shows the risk of breakthrough cases is very small for vaccinated people, potentially 1 in 5,000.
  • Additionally, the risk of being hospitalized from COVID-19 after vaccination is extremely small, at about 5 in 100,000.
  • A new study found people who were not vaccinated were five times as likely to get COVID-19 compared to people who were fully vaccinated.

According to the Centers for Disease Control and Prevention (CDC), the risk of hospitalization or death from COVID-19 is significantly lower for vaccinated people. However, the CDC also emphasizes that no vaccine is 100 percent effective.

So-called “breakthrough infections” have been reported in many people who have been fully vaccinated. In extremely rare cases, some vaccinated people have been hospitalized or died after developing COVID-19.

But what are the facts about these cases? Do we really need to worry about becoming sick with COVID-19 after vaccination?

Shereef Elnahal, MD, president and CEO of University Hospital in Newark, New Jersey, and former commissioner of the New Jersey Department of Health, told Healthline that, first of all, getting vaccinated is one of the most important things you can do to protect yourself from COVID-19.

“Being fully vaccinated substantially reduces your risk of infection and reduces your risk of hospitalization and death by an even greater degree,” he said. “In fact, it is one of the most important things you can do, if you’re unvaccinated.”

Elnahal said he began to see breakthrough infections for the first time over the last few weeks, some of which have even resulted in death.

But the risk is still very low for vaccinated people.

A new study from the CDC published Friday finds that people who are vaccinated were far less likely to develop COVID-19 and to be hospitalized or die from the disease.

Compared to people who were not vaccinated, people who were vaccinated were five times less likely to develop COVID-19. They were 10 times less likely to be hospitalized and die from the disease.

A New York Times report used data from U.S. areas with detailed information on breakthrough cases. It estimated for most vaccinated people, the risk is about 1 in 5,000 for breakthrough infections. In areas with a low transmission rate, it’s about 1 in 10,000.

“Breakthrough hospitalizations are obviously concerning because the people are sick enough, despite having been vaccinated, to require hospitalization,” Elnahal said. “But it’s important to emphasize that the risk of death is still very low, even if you require hospitalization, as a vaccinated person.”

According to Elnahal, what we’re seeing is the effects of both waning immunity from vaccination and the Delta variant, which is twice as infectious as the original coronavirus variant, happening at the same time.

“It’s the confluence of those two things that’s causing the problem right now,” he said. “So I do hope that boosters for the general public come sooner rather than later.”

Breakthrough cases have been on the rise — and making headlines — in the United States as the more infectious Delta variant has surged.

However, breaking down the raw numbers on vaccination rates and post-vaccination infections reveals how effective the COVID-19 vaccines are at protecting against hospitalization and death.

As of Sept. 7, more than 176 million people have been fully vaccinated against COVID-19 in the United States. The number of vaccinated people who have been hospitalized or died from COVID-19 is a minuscule fraction of that number, according to CDC data.

A total of 11,440 people were hospitalized for COVID-19 after being vaccinated. However, 2,491 of these people had no COVID-19 symptoms or were hospitalized for another condition.

So that means 8,949 people were hospitalized related to COVID-19 symptoms after being vaccinated.

This means the risk of being hospitalized for COVID-19 after vaccination is 0.00005 percent.

Additionally, 2,675 deaths were reported in vaccinated people, with 493 of these deaths in people who did not have symptoms of COVID-19, or their death was unrelated to COVID-19.

This means 2,182 vaccinated people died after developing COVID-19-related symptoms.

That means the risk of dying from COVID-19-related illness after vaccination is 0.00001 percent.

A second study published from the CDC on Friday found that Moderna vaccine recipients appeared to have the highest amount of vaccine effectiveness at 95 percent.

Those with Pfizer-BioNTech had about 80 percent effectiveness while those with Johnson & Johnson had about 60 percent. Overall vaccine effectiveness against hospitalization was 86 percent total.

Asked whether the likelihood of breakthrough infection is different for an mRNA vaccine versus an adenovirus vector vaccine like the Johnson & Johnson shot, David Hirschwerk, MD, an infectious disease specialist at Northwell Health in Manhasset, New York, said direct comparisons are still difficult.

“In the vaccine clinical trials, the mRNA vaccines did result in better performance compared to the J&J shot at preventing breakthrough infection,” he said. “However, all vaccines performed similarly with respect to prevention of severe disease.”

Hirschwerk added that the populations of clinical trial participants differed significantly, so direct comparisons should only be made with caution.

According to Miriam Smith, MD, chief of infectious disease at Long Island Jewish Forest Hills in Queens, New York, “Breakthrough infection with SARS-CoV-2 is very low and is estimated at around .02 percent based on clinical trial data, with J&J breakthrough somewhat more common.”

Elnahal pointed out that coinfection with flu and COVID-19 is possible.

“That’s a problem in particular for higher-risk people,” Elnahal said. “Because people with the same comorbidity that portend for a worse COVID outcome also have conditions that portend for a worse flu outcome.”

He explained that COVID-19 is “significantly worse than the flu” for the average person, and he doesn’t think having both at the same time is something he would want to experience.

According to Elnahal, the timing of a COVID-19 booster shot coincides well with the need to get a flu shot.

“The Advisory Committee on Immunization Practices exclusively weighed in on this question about whether you could give both the flu shot and the COVID vaccination at the same time,” Elnahal said. “And they said that that was acceptable.”

“We are hearing a lot of good things about Pfizer being authorized by the FDA for a third dose for most people as soon as by the end of this month,” Elnahal said. “I really hope that comes through.”

He added that he hopes people who received the Moderna or Johnson & Johnson vaccine will be authorized to get a dose of the Pfizer-BioNTech vaccine as a booster, should that come through by the end of the month.

“Because every indication is that these authorizations are going to be sequenced,” he said.

Elnahal explained there are many people in particular who received the Moderna vaccine who are well past the 8-month mark of booster eligibility.

“The CDC and the FDA are starting to agree that a booster is likely needed,” he said. “We don’t have full confirmation or full authorization yet on that, but it’s something I do hope comes soon.”

According to Elnahal, the New Jersey Hospital Association released a new report that showed 73 percent of hospitalized people in New Jersey have not had any dose of a vaccine.

He emphasized the need to be “extra vigilant” as school starts, we return to the office, and people are out and about more this fall.

“It is important to not let your guard down. It’s important to wear masks indoors when possible, especially at large indoor events, and simply to just get vaccinated,” he said. “That is the most important thing you can do to protect yourself from this.”

Breakthrough infections can and do happen to people who have been fully vaccinated against COVID-19.

However, the risk is very miniscule. COVID-19 vaccines offer considerable protection against severe disease.

Experts say the Delta variant and waning immunity are causing many of the increased breakthrough cases, but booster shots will provide increased protection.

They also say it’s possible to have COVID-19 and the seasonal flu at the same time, so getting the booster once it’s approved plus a flu shot is a good idea.