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Why Vaccines May Not Protect You Against Delta COVID

Just because you are vaccinated doesn't mean you can't catch the Delta COVID variant. You will survive, but you could become a long hauler.
Why Vaccines May Not Protect You Against Delta COVID
Doctor with a positive blood sample for the new variant detected of the coronavirus strain called covid DELTA. Research of new strains and mutations of the Covid 19 coronavirus in the laboratory

You have heard repeatedly that vaccination is the answer to COVID-19. But the Delta variant has changed the game. Don’t get me wrong. We are big believers in getting vaccinated. I was an early adopter! I got my first Pfizer/BioNTech shot on January 12, 2021, and my second shot on February 2, 2021. But here’s the problem. Although the vaccine may keep you alive and out of the hospital, it may not prevent you from catching the Delta COVID variant!

Vaccines vs. the Delta COVID Variant: Provincetown, MA:

We first got suspicious when we learned about the Provincetown, MA outbreak earlier this summer.

The CDC described the July outbreak in its MMWR Weekly Report (Aug. 6, 2021)

“In July 2021, following multiple large public events in a Barnstable County, Massachusetts, town, 469 COVID-19 cases were identified among Massachusetts residents who had traveled to the town during July 3–17; 346 (74%) occurred in fully vaccinated persons. Testing identified the Delta variant in 90% of specimens from 133 patients.”

Since that report the Ptown cluster has climbed to over 1,000 people. Most were vaccinated. That’s what worried us. There is some good news, though.

Massachusetts Governor, Charlie Baker, was quoted in the Berkshire Eagle (Aug. 12, 2021)

“‘I think in some respects, Provincetown was as big a test as you could possibly put a vaccine through,’ Baker said. ‘The significant number of people who were there were vaccinated, it was an enormous crowd, a three-day rainy weekend in Provincetown where everybody talked about the fact that it was a lot of close quarters in restaurants and bars and households.

‘And yet, in a cluster with more than 1,000 people, only seven people were hospitalized, and one person died, and the person who died had a lot of complexities,’ he said. ‘And I think in some respects, the vaccines have proven their effectiveness, and we should do everything we can to encourage people to get vaccinated.’”

We don’t disagree with Governor Baker that the vaccines protected people from severe illness and death. But the shots did not prevent fully vaccinated people from catching the Delta COVID variant! Nearly 3/4 of the breakthrough cases were in vaccinated individuals. 

A Southern Wedding and the Delta COVID Variant:

A few weeks ago we heard about a woman who traveled to a Southeastern state in July to attend a wedding. It was an outdoor event. There were 40 adults and 15 children.

All the adults were fully vaccinated. The woman caught COVID, as did 12 of the 40 adults, even though the event was outside. Read the full story at this link. People who had received the Moderna vaccine seemed better protected than those who got the Pfizer/BioNTech shots.

Science Supports the Wedding Story:

Researchers at the Mayo Clinic compared the effectiveness of both vaccines from January to July 2021 (MedRxiv, Aug. 9. 2021). During the early part of that period, the alpha variant predominated, but by July, the Delta variant had taken over. The study found that the Pfizer vaccine was only 42% effective against infection with the Delta variant in July. Moderna fared better. It was 76% effective.

The researchers report that people vaccinated with the Moderna vaccine:

“…were about half as likely to experience breakthrough infections as individuals vaccinated with” the Pfizer/BioNTech shot.

We have no horse in this race. As mentioned above, I got my Pfizer/BioNTech shots early in 2021. This is preliminary research. Only time will tell whether the Moderna vaccine continues to fare better against the Delta COVID variant.

Israel Is Battling the Delta COVID Variant Despite 80% Vaccination:

Everyone acknowledges that Israel beat other countries in vaccinating most of its population very quickly. The Pfizer shots were the dominant vaccines.

A month ago, it appeared as if Israel was almost back to normal. People were eating in restaurants, going to concerts and exercising in gyms. But COVID is back. Even vaccinated people are catching the Delta COVID variant. Public health authorities are contemplating new lockdowns. That’s because the data from July suggested that the Pfizer/BioNTech shots were only 39% effective against the Delta COVID variant. 

What’s Going On with the Delta COVID Variant?

First, the good news. The vaccine is extraordinarily effective at preventing hospitalizations and deaths. Not perfect, but really quite impressive. That said, the shots are not keeping people from catching COVID.

Reporters are calling these breakthrough infections. I’m not sure that is the best terminology. It implies that these are rare events. I suspect that they are far more common than public health authorities would like to admit.

Millions of people were ready to party once they were fully vaccinated. This week more than 700,000 people are attending the Sturgis Motorcycle Rally in South Dakota. Even if many of those attending are vaccinated, this could be a super-super spreader event!

Dr. Eric Topol is one of our heroes. We have been interviewing him on our syndicated public radio show for decades. That started when he was a practicing cardiologist at the Cleveland Clinic. Now he is a professor in the Department of Molecular Medicine and executive vice president at Scripps Research and the founder and director of the Scripps Research Translational Institute.

He told the New York Intelligencer (Aug. 12, 2021)

“‘We’re seeing a lot more spread in vaccinated people,’ agreed Scripps’s Eric Topol, who estimated that the vaccines’ efficacy against symptomatic transmission, which he estimated to be 90 percent or above for the wild-type strain and all previous variants, had fallen to about 60 percent for Delta. ‘That’s a big drop.’ Later, he suggested it might have fallen to 50 percent, and that new data about to be published in the U.S. would suggest an even lower rate.”

“‘The breakthrough problem is much more concerning than what our public officials have transmitted,’ Topol continued. ‘We have no good tracking. But every indicator I have suggests that there’s a lot more under the radar than is being told to the public so far, which is unfortunate.’”

What Does the Delta COVID Variant Mean for You?

First, let me be absolutely clear. I believe the vaccines help prevent serious illness, hospitalizations and deaths from COVID-19. And I am not just implying that a few people are protected. The data that I have reviewed suggest that the vaccines are still around 90% effective in preventing bad things from happening even if people catch COVID.

That’s the very good news. Here’s the very bad news. I suspect that a lot of vaccinated people are behaving as if they are fully protected against the coronavirus. They have given up their masks and are shopping in grocery stores, big box discount emporiums and hardware and garden retailers, to name just a few locales. They are getting their hair cut, going to banks and bars and trying to get back to a normal existence.

I suspect that a great many of these folks are going to catch the Delta COVID variant. They might not get very sick. They might not end up in the hospital. They probably won’t die. But they will catch COVID. They will spread COVID. And they could end up with Long COVID!

Why Long COVID Matters:

You have heard of “long haulers.” These are people who recover from COVID-19. Some had mild symptoms. Others were asymptomatic. Some were pretty darn sick. What they all have in common is continuing symptoms. And those symptoms can be life changing!

We now know that people who were fully vaccinated and caught COVID anyway can have persistent symptoms after they recover (New England Journal of Medicine, July 28, 2021). No one yet knows how many vaccinated people who catch COVID-19 will go on to develop long COVID (aka post COVID syndrome [PCS], Post-acute sequelae of SARS-COV-2 [PASC], chronic COVID, etc.). It could be a small number or it could go as high as 30% to 40%. That is the estimate of how many people develop this condition if they catch the virus without being vaccinated.

How Bad Is Long COVID?

Bad! Symptoms can include unrelenting fatigue, breathing difficulties and/or shortness of breath, cough, chest pain, muscle aches and joint pain, brain fog, insomnia, head pain, loss of taste or smell, dizziness upon standing, rapid heart rate, etc. You can read more about other symptoms and the prognosis at this link

If you want to learn what it’s like to have this condition, here is a link to our podcast with two health professionals who themselves have experienced Long COVID. 

The Bottom Line:

If you have been vaccinated, you are not guaranteed protection against the Delta COVID variant! You probably won’t get terribly ill and you probably won’t die if you get sick, but if you develop long COVID you will be sorry. That is why you need to be careful. I do not like wearing a tight-fitting N95 mask when I am out and about, but I do!

I am back to wearing the mask even when I am outside and around people. I wear it because of that wedding I described in the Southeastern US where 12 out of 40 adults came down with COVID-19.

What’s more, a huge number of people in Ptown who were vaccinated caught the coronavirus. To top it off, a recent outdoor event at the UNC Eshelman School of Pharmacy in Chapel Hill, NC, led to several people catching the virus, even though they were vaccinated. Please be careful!

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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