Benefits of COVID-19 mRNA vaccines outweigh their risks, even for teenagers, contrary to Alex Berenson’s claim

“1 million mRNA covid shots or teens will prevent 0-1 deaths and CAUSE 100,000 - 200,000 severe side effects”
Lack of context: The claim didn’t make clear that the “severe” reactogenic events are normal following vaccination and aren’t synonymous with serious medical issues. The claim also didn’t make clear that very few teenagers die of COVID-19, which explains why vaccination doesn’t appear to prevent many COVID-19 deaths.
Preventing death isn’t the main motivation for COVID-19 vaccination in teenagers because this age group is at a very low risk of dying from the disease to begin with. Rather, the advantages lay mainly in reducing their risk of severe disease, long COVID, and ability to transmit to others. Reactogenic events are expected following vaccination and are a consequence of the vaccine’s stimulation of the immune system. Severe reactogenic events only mean that the person was unable to work or perform domestic activities right after vaccination, which don’t necessarily imply long-term health problems.

FULL CLAIM: “1 million mRNA covid shots or teens will prevent 0-1 deaths and CAUSE 100,000 - 200,000 severe side effects”


On 12 September 2023, the Advisory Committee on Immunization Practices (ACIP) of the U.S. Centers of Disease Control and Prevention (CDC) held a meeting discussing COVID-19 vaccines.

Writer Alex Berenson used data presented at this meeting to claim that “1 million mRNA covid shots or teens will prevent 0-1 deaths and CAUSE 100,000 – 200,000 severe side effects”. The juxtaposition of this seemingly low number of prevented deaths and a seemingly high number of “severe side effects” implied that mRNA vaccines weren’t worth the risk for teenagers. Multiple social media profiles later spread similar claims. However, this implication lacks the necessary context and can mislead readers.

A small number of vaccine-prevented COVID-19 deaths among teenagers is expected, and not a sign that vaccines are ineffective

Data presented at the ACIP meeting did indicate that COVID-19 vaccination prevented zero to one COVID-19 deaths per million of administered doses over a period of six months in the 12 to 17 age group (slide 65). While this is low, it’s important to keep in mind that young people are the least likely to die from COVID-19.

According to the CDC, there were 3,019 COVID-19 deaths in the U.S. in the 15 to 24 age group since the beginning of the pandemic, and 509 in the 5 to 14 age group. The COVID-19 mortality rate in 2022 was 0.5 deaths per 100,000 persons in the 5 to 14 age group and 1.5 per 100,000 in the 15 to 24 age group. These are the lowest mortality rates of all age groups.

In contrast, the 2022 COVID-19 mortality rate for the 35 to 44 age group was 11.9, climbing even further to 158.1 in the 65 to 74 age group.

Another sign of the low risk of COVID-19 mortality in young people is the infection fatality ratio (IFR). This measures the ratio between the number of COVID-19 deaths and the number of SARS-CoV-2 infections. The IFR for people between 12 to 17 years ranges from 0.0036% to 0.0085% and is lower than the IFR for the rest of the population, according to a study published in The Lancet[1].

Therefore, the small number of COVID-19 deaths prevented by vaccination in the 12 to 17 age group doesn’t mean that COVID-19 vaccines are ineffective, but that there are very few deaths to be prevented in the first place compared to older age groups.

It is also important to keep in mind that preventing death is not the sole aim nor the only benefit of vaccination. COVID-19 vaccines also reduce the risks of severe disease, long COVID and transmission of the disease to others, albeit to varying degrees depending on the virus variant and the amount of time that has passed since vaccination[2-4]. Therefore, it is misleading to question the vaccines’ utility based on one outcome that has very little chance of occurring in the first place (death) while overlooking other potential benefits of vaccines.

Severe reactogenic events can be expected after vaccination and don’t reflect a health-threatening condition

The claim is also misleading in affirming that one million doses of COVID-19 vaccine among teenagers will cause 100,000 to 200,000 severe side effects. This is a misrepresentation of the clinical data from slide 52 of the ACIP meeting presentation. The term “severe side effects” may be understood by the layperson as dangerous medical problems triggered by vaccination. However, the data from slide 52 describe severe reactogenic events, which are a different and less worrisome concept. We explain why below.

First, reactogenic events are perfectly normal following vaccination. This Nature review defines reactogenic events as “a subset of reactions that occur soon after vaccination, and are a physical manifestation of the inflammatory response to vaccination”[5]. Some classic reactogenic events are redness, pain at the injection site, fever, and headache. Vaccines work by triggering an immune response to train the immune system against a given pathogen, so reactogenic events make up common side effects of vaccination. That said, not everyone experiences reactogenic events from vaccination, and the absence of such events doesn’t mean the vaccine didn’t work.

Second, “severe” in severe reactogenic events doesn’t necessarily mean that such events have dire consequences on someone’s health. Slide 52 specifically focuses on these reactions because knowing whether or not vaccines are associated with a lot of severe reactogenic events is part of the ACIP decision process on vaccine recommendations—as explained here for the Moderna vaccine and here for the Pfizer-BioNTech vaccine.

Severe side effects are those of grade 3 or 4, and the CDC defines grade 3 as “prevents daily routine activity or requires use of a pain reliever” and grade 4 as “requires emergency room visit or hospitalization”.

So, this means that if someone had to stay home after vaccination because of a sore arm or a fever, it would be rated as grade 3 and counted as a severe reactogenic event. But neither of the two can reasonably be considered a dangerous medical condition. Such reactions could also happen following a wide range of common and non-threatening events, like common cold.

The data in slide 52 don’t distinguish between grade 3 and grade 4 events, so it’s not possible to determine how many reactogenic events required an emergency room visit or hospitalization. However, it is possible to obtain a bit more information from the U.S. Food and Drug Administration (FDA) meeting that led to the authorization of the mRNA vaccines for teenagers.

The meeting document related to the authorization of the Moderna vaccine for people aged 12 to 17 mentioned that no grade 4 reactions were observed in the seven days post-vaccination (page 39 to 42). Similarly, the Pfizer-BioNTech clinical data for people aged 12 to 15 reported no grade 4 reactions[6].

Therefore, data indicated that vaccination was associated with expected, short-term reactogenic events that necessitated staying at home. Contrary to what the claim implied, the data didn’t show health-threatening side effects.


Berenson combined CDC data about the number of vaccine-prevented COVID-19 deaths and the number of reactogenic events following vaccination to imply that COVID-19 vaccines weren’t worth the risk for teenagers. But this implication leaves out some crucial context, misleading readers.

Reactogenic events following vaccination are normal and expected. They are signs that the immune system is responding to the vaccine. Clinical trials of the Pfizer-BioNTech and Moderna mRNA vaccines didn’t report reactogenic events necessitating emergency room visits or hospitalization. Between 10% and 25% of vaccine recipients experienced reactions that kept them from performing daily activities like domestic tasks or working. While this can understandably be seen as an annoyance, it isn’t evidence that vaccination deteriorates the body, in spite of what the term “severe event” could suggest.

While the number of COVID-19 deaths prevented by vaccination is low, teenagers are at a very low risk of dying from COVID-19 in the first place. So there are few deaths to be prevented to start with. For teenagers, the key benefits of vaccination lay elsewhere, in reducing the risk of severe disease, of potentially debilitating long COVID, and of transmitting to other potentially more vulnerable people like the elderly.



Published on: 25 Sep 2023 | Editor:

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