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Samantha Putterman
By Samantha Putterman October 7, 2021

No evidence that COVID-19 vaccines weaken the immune system

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  • Multiple medical experts said the blood test results featured in the video to support this claim didn’t come close to showing an immune system that has crashed. 

  • This wasn’t observed in the COVID-19 vaccine trials where blood counts were obtained, experts said.

A chiropractor from Illinois caused a stir online after he posted a YouTube video that he said  showed a patient’s blood work before and after they received two doses of a COVID-19 vaccine.

In the video, Nathan Thompson, the president of Exemplify Health Center, claimed the results showed that the shots made the immune system "tank" and that "it can't be false because this is medical testing." 

The video was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

Thompson avoided saying or spelling out the word vaccine throughout the video to skirt YouTube’s regulations on vaccine misinformation, but it was still taken down. By then, however, his message had already jumped to other websites.

Thompson said he ran blood work for a type-2 diabetic patient before the man was compelled by his employer to get the COVID-19 vaccine. The results shown appear in the "normal" range. In subsequent panels, which Thompson said were collected after the patient received his first and second doses, the numbers changed.

For example, the post-second dose results show that the man’s granulocytes — a type of white blood cell that contains proteins that help the body fight bacterial infections —  went from 58.9 to 79.6. Meanwhile, his lymphocytes — white blood cells that include natural killer cells and immunity-building T and B cells — dropped from 33.8 to 13.8, the results showed.

"His adaptive immune system absolutely has tanked," Thompson said.

We asked multiple medical experts to review those results, and they said the numbers don’t come close to showing a crashed or suppressed immune system. Meanwhile, there has been no evidence in clinical trials where blood counts were taken that the COVID-19 vaccines weaken the immune system.

"These types of changes (in lab work) frequently occur," said Dr. Stanley Perlman, a professor of microbiology and immunology at the University of Iowa. "Things change all the time without it mattering much. In the absence of more information, these numbers don’t mean anything to me."

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"There are all kinds of variations that happen when you measure the immune system and there's going to be some natural fluctuation that occurs," said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security. "As someone who looks at CBC (complete blood count) panels for patients all day, those numbers aren’t worrisome and don't constitute the immune system ‘crashing’." 

Research from the CDC and others show that the vaccines boost the body’s immune response, not lower it. For example, one Aug. 13 CDC report found that people who had been infected with COVID-19 in 2020 got a dramatic boost in virus-killing immune cells later because they were vaccinated.

Dr. Paul Offit, director of the Vaccine Education Center and an attending physician in the Division of Infectious Diseases at Children's Hospital of Philadelphia, said the suggestion that the immune system is weakened by the COVID-19 shots rather than bolstered by them isn’t supported by clinical trial data, which includes thousands of people.

"This wasn't observed in any of the phase 3 trials, where complete blood counts were obtained," he said.

Different types of vaccines work in different ways to offer protection, but with all types, the body is left with a supply of T-lymphocytes and B-lymphocytes that will remember how to fight that virus in the future. Vaccines help develop immunity by imitating an infection and can sometimes cause symptoms, such as fever. 

Some believe that natural immunity from having COVID-19 itself is better than the immunity provided by vaccines. But natural infections can cause severe complications and be deadly. This is true even for diseases that many people consider mild, like chickenpox. It is impossible to predict who will get serious infections that may lead to hospitalization and people are often leaving it up to chance by not getting vaccinated, health experts say.

Our ruling

In a video a chiropractor claims that the blood work results of a patient before and after they received two doses of a COVID-19 vaccine show that the shots caused the immune system to "tank."

Multiple medical experts reviewed screenshots of the lab results and said they were meaningless without more information and didn’t reflect a crashing or suppressed immune system. 

The notion that vaccines weaken the immune system wasn’t observed in clinical trials for the vaccines where blood counts were obtained, experts said.

We rate this False.

Our Sources

YouTube video, Sept. 28, 2021

The Centers for Disease Control and Prevention, Understanding How COVID-19 Vaccines Work, Updated May 27, 2021

The Centers for Disease Control and Prevention, Myths and Facts about COVID-19 Vaccines, Updated Oct. 4, 2021

The Centers for Disease Control and Prevention, Reduced Risk of Reinfection with SARS-CoV-2 After COVID-19 Vaccination — Kentucky, May–June 2021, Aug. 13, 2021 

Food & Drug Administration, PFIZER-BIONTECH COVID-19 VACCINE (BNT162, PF-07302048) VACCINES AND RELATED BIOLOGICAL PRODUCTS ADVISORY COMMITTEE BRIEFING DOCUMENT, Dec. 10, 2020 

ClinicalTrials.gov, Study to Describe the Safety, Tolerability, Immunogenicity, and Efficacy of RNA Vaccine Candidates Against COVID-19 in Healthy Individuals, Last updated Aug. 26, 2021

Associated Press, COVID-19 vaccines don’t destroy T cells or weaken immune system, Aug. 26, 2021

Phone interview, Dr. Amish Adalja, senior scholar at Johns Hopkins University Center for Health Security, Oct. 7, 2021

Phone interview, Dr. Stanley Perlman, professor of microbiology and immunology at the University of Iowa, Oct. 7, 2021

Email interview, Dr. Paul Offit, director of the Vaccine Education Center and an attending physician in the Division of Infectious Diseases at Children's Hospital of Philadelphia, Oct. 7, 2021

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No evidence that COVID-19 vaccines weaken the immune system

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