Dr. Sanjay Gupta: The term “breakthrough infection” raises questions about vaccines, but it shouldn’t.

But at the same time, many of us know people who test positive for the coronavirus and show symptoms after being completely vaccinated. I also know some. Maybe it’s your child’s teacher, your brother-in-law, your neighbor, your colleague or your mechanic. And the great news is that you can leave chicken soup in their doors instead of attending their memorial service, but it’s probably because it makes the phenomenon look very realistic and not “rare” at all. You should stop explaining to. In fact, vaccinated individuals are not tested very often, so it is not known how common these infections are in practice.

From the whole situation, I started to think about the term “breakthrough infection” and whether it was the correct expression. I don’t seem to have enough nuances to explain what’s going on. It only helps warn our people who are already vaccinated and can discourage those who are hesitant.

In search of better terms

I quickly learned that some scientists didn’t like the word “breakthrough infection.”

“I hate it because it emphasizes a lot [other] “I know about vaccines,” said Dr. Carlos del Rio, a prominent medical professor at Emory University School of Medicine’s School of Infectious Diseases. He says he has the illness. We talked about effectiveness. … I think breakthrough is a term equivalent to lack of effectiveness. ”

Del Rio said the vaccine was specially designed to protect against severe illness and death, which was what their large-scale vaccine trials sought. “In these studies, infection was by no means an endpoint,” he said.

He later found that the vaccine prevented the infection, “a little … like a cherry blossom on a cake.”

The phrase was also immunoscientist and virologist Dr. Bernie Graham, Deputy Director of the National Institute of Allergy and Infectious Diseases Vaccine Research Center, whose laboratory played an important role in the development of the Moderna vaccine.

Graham described it in a way that really visualizes the effects of the vaccine on your body.

“Vaccines have always been designed to focus on diseases of the lower respiratory tract [the lungs] -Not the upper respiratory tract [the nose and upper throat], “He explained.

Think about it. According to Graham, when the virus enters the lungs, people become seriously ill, and that’s where the vaccine provides the most protective barrier. As you can see, the vaccine causes the production of immunoglobulin, a protein that acts as an antibody. The main product produced by the vaccine is immunoglobulin G (IgG), which can easily move from the blood to the lower respiratory tract (lungs), where it can block the virus. The levels of IgG in the blood required to penetrate the tissues of the upper respiratory tract (nose and throat) are much higher, so it is more difficult to stop the virus from multiplying in the nose.

“Therefore, we see this consistency in efficacy against serious illnesses. It wasn’t designed to protect the upper respiratory tract so much,” he explained.

That’s why Graham said scientists didn’t expect the vaccine to prevent the infection so much. “I was very fortunate to be able to do that to some extent against the previous strain,” he added.

And because delta variants are more contagious, more infections will definitely occur overall with both vaccination and non-vaccination, but compared to protection against mild or asymptomatic disease. There is a big difference between the two groups when it comes to protection against severe illness, Graham explained. This is evident from the data showing that the overwhelming majority of hospitalizations and deaths occur unvaccinated rather than vaccinated.

Dr. Anthony Fauci, President Joe Biden’s Chief Medical Advisor, NIAID Director and Graham’s Boss, agrees.

“Vaccines do exactly what we want them to do when it comes to keeping you away from the hospital, protecting you from serious illness and ensuring your death,” Fauci said last week at the White House. I mentioned in the Covid-19 Response briefing.

“The important point to raise is that even with a high degree of protection, the higher the proportion of people vaccinated, the higher the absolute number of breakthrough infections may appear,” he said. I did.

But that’s because more people have been vaccinated. It’s simple math. Think of it as follows. If 100% of people are vaccinated, all new infections need to be transmitted to those who have been vaccinated, right? But in that scenario, only a few dead people will die on Covid-19. Over 99% of the deaths we see now will almost certainly be avoided.

Another way to understand seemingly many things: If one million people are vaccinated against the false virus “X” and 1% are infected, the number of vaccinated people will be 10,000. But if 100 million people are vaccinated and 1% are infected, that would be 1 million people infected. Obviously one million makes 10,000 an order of magnitude larger, but it’s still the same percentage, 1%.

According to Forch, the “critical number” is the percentage of people vaccinated with breakthrough infections, not the raw number. And in that number of lives, serious illness and death are the consequences we desperately want to avoid.

As he reiterated at the White House briefing, “The Covid Vaccine provides strong protection against delta mutants and protects you, your family, and your community … about the disease itself. Is a one-eighth reduction. In the case of hospitalization, it is a one-fifth reduction. Due to the reduction and death, a one-fifth reduction. ”

However, it is difficult to determine the exact number of “breakthrough infections”. Again, partly because there is no national data available for asymptomatic, mild, breakthrough cases. Also, instead of testing the vaccine on a regular basis, only those who are experiencing symptoms or who need to have a negative Covid test on their trip are tested.

For example, I recently went to Tokyo for the Olympics and took several tests before and during my trip. I was fine and very careful, but if one of those tests returned positive, I wouldn’t have been completely shocked yet. Fortunately, they didn’t.

Immunity weakens over time

Another factor that can affect the number of so-called breakthrough cases (and our perception of how effective the vaccine is) is that the level of coronavirus antibody is due to natural infection or vaccine. It generally declines over time, whether or not it is earned.

Scientists are spending time studying immune problems, and more data is needed to ensure that protection from the coronavirus lasts. However, the fact that the immunity of a vaccinated person is found to be weakened months or years after the second shot does not mean that the vaccine is not working.

“This is not a glitch,” said Dr. Monica Gandhi, a professor of medicine at the University of California, San Francisco and San Francisco General Hospital, and deputy director of HIV, infectious diseases, and global medicine.

“This is how the immune system is designed,” she explained. “It is normal for immunoglobulins to decrease over time.” She said that our blood and nose cannot carry all the antibodies that have been produced so far. If antibody levels do not drop, “our blood will be thick like a paste.”

And as our antibodies decline in places like our nose where the virus may invade our body, Gandhi said we may be susceptible to mild infections. ..

“So it’s not really a function of the vaccine. It has to do with how our immune system works,” she said.

At the same time, our immune system is fairly smart and witty. It contains cells, such as Memory B cells, that begin mass-producing new antibodies within a few days of encountering familiar viruses and bacteria.

According to Gandhi, once antibody levels have dropped, a mask can be worn to avoid mild exposure. You may then consider getting a booster shot or eventually an intranasal vaccine (not yet on the market). The US Food and Drug Administration is expected to make an immediate decision on boosters.

Transmissible issues

As an additional bonus of being vaccinated (or previously infected with Covid), Gandhi attacks the virus when T cells, another important immune system soldier, encounter the virus in our nose. , Said to weaken. Therefore, the detection of a genetic material in the virus by the Covid-19 test does not mean that the virus is as infectious as an unvaccinated person.

Both Gandhi and Graham pointed out this important point. The viral load (the amount of virus in an infected person’s body) also seems to decrease much faster with vaccination than with unvaccinated. This has a significant impact on infectivity.

Graham explained that while it is true that delta mutants produce higher initial viral load than previous strains, vaccination causes the viral load to drop faster and people do not shed it for longer.

“Currently, there are data suggesting vaccination and non-vaccination. [people] It’s at the same level at some point, “Graham said. … the virus in vaccinated people is much less than in unvaccinated people. Therefore, vaccinated people will have less infection, but there may be some infection … it’s a matter of degree. There is a little nuance. “

When to change?

So it may be time to shelve the word “breakthrough infection” and look for a new name. After all, vaccines are not like building an inaccessible fortress around our home. It’s like deploying a sentry (lookout) that can warn you of an imminent attack early and be ready to defend your rank-and-file immune system soldiers.

Another phrase I’ve heard in some circles is “post-vaccination infection.” I like it because it doesn’t mean vaccine failure-it’s just a neutral term of what we expect to happen to some people over time.

As Emory’s Del Rio pointed out, words are important. “I think it’s a breakthrough, but it may be a virologically and technically correct term, [for the general public] That may not be the correct term. “

Dr. Francis Collins, director of the National Institutes of Health, also finds it misleading.

“I think the term is terrible because it scares people and sounds like the vaccine doesn’t work. To be clear, vaccines are very effective in preventing hospitalization and severe cases. Over 90%. So don’t let the language get in the way, “he told CNN last week.

I sincerely agree. In fact, at this point, nothing gets in the way of vaccination.