On Friday, February 7, a hearing took place in the Montana state legislature on a bill that would ban the use of mRNA vaccines in humans. The bill was sponsored by State Representative Greg Kmetz with the support of other Republicans, and if it were to pass into law this would mark a first in the United States.
Key facts:
- A bill proposed in the Montana state legislature seeks to outlaw the use of mRNA vaccines in humans.
- mRNA vaccines, such as those used to prevent COVID-19, have been extensively studied and are considered safe and effective.
- The bill contains several misconceptions about mRNA vaccines, such as the false idea that the RNA can integrate into human DNA.
mRNA vaccines came to public prominence during the COVID-19 pandemic, as this technology was used to create arguably the most successful vaccines against the disease, which remain the gold standard for COVID prevention today. Millions of people have received doses of mRNA vaccines manufactured by Pfizer-BioNTech or Moderna, and the shots are still being updated to combat more recent virus variants.
Alongside non-mRNA vaccines, such as the Oxford-AstraZeneca vaccine, these shots are estimated to have saved millions of lives. A 2024 study in The Lancet suggested that 1.6 million lives (adults over 25) had been saved in the World Health Organization European Region alone between December 2020 and March 2023.
The technology that brought us the mRNA COVID vaccines even won a Nobel Prize in 2023. Beyond COVID, the same innovation is being put to use in trials of personalized vaccines to treat brain, bowel, and skin cancer, to name a few.
But even with all the data in their favor, mRNA vaccines have had their strong detractors from the very start. Kmetz himself has previous in this area, having sponsored a 2023 bill that sought to prevent COVID vaccine recipients from donating blood.
Much of the opposition appears to be based on misunderstandings around how these vaccines work – and looking at the text of the new Montana bill, we can see some of that creeping in.
mRNA vaccines cannot alter your DNA
The misapprehensions start very early on. When detailing the reasoning behind the bill, it states that “the mRNA vaccines may integrate into the human genome and be passed onto the next generation.” This is a common argument that’s made against mRNA vaccines, but it’s simply not true.
mRNA cannot integrate itself into the genome inside human cell nuclei, nor can it alter a DNA sequence. The two molecules are very different in structure. The mRNA would first need to be reverse transcribed into DNA, which is not possible without the help of an enzyme called reverse transcriptase. Since this is not present in these vaccines, this is not something we need to worry about.
These fears were sparked anew after an unreviewed preprint study was posted online in late 2023, mentioning “DNA fragments” present in mRNA COVID vaccines. As reported by Reuters in February 2024, Florida Surgeon General Dr Joseph Ladapo cited this preprint in statements raising concerns about the possible adverse impacts of these DNA fragments.
However, these fragments are just residue left over from the manufacturing process. Experts told Reuters that as well as not being able to get into our cells’ nuclei in the first place, these DNA fragments are lacking the essential enzyme, called integrase, that would allow them to meld with existing DNA.
“So, it’s impossible; it’s virtually impossible for these DNA fragments to do any harm. They are clinically and utterly harmless,” said Dr Paul Offit, a vaccine scientist at the Children’s Hospital of Philadelphia.
This same message was reiterated by the UK Medicines and Healthcare products Regulatory Agency in response to a Freedom of Information request on the question of whether residual DNA could pose a risk:
“We are also not aware of any scientific evidence showing that the small amounts of residual DNA that may be present in the vaccine, could transfect into cells and integrate into the DNA of a vaccinated person.”
mRNA vaccines do not cause “shedding”
The bill also mentions the risk of “shedding”. This is something antivaxx activists frequently refer to, but in reality it’s a very rare phenomenon that is only applicable to a subset of vaccines.
With live vaccines – those that contain complete viruses that have been weakened (attenuated) – it is theoretically possible for immunized individuals to “shed” virus particles, for example in their stool, for a period of time. Live vaccines in use today include the chicken pox vaccine and the MMR. It’s rare for these shed viruses to reach a level where they could be transmitted to another person, and in any case this is not generally harmful as the virus has been weakened before inclusion in the vaccine.
mRNA COVID vaccines are not live and do not contain complete SARS-CoV-2 virus particles, therefore shedding is not a possibility.
The benefits of mRNA vaccines outweigh the risks
No medical treatment, intervention, or procedure can be said to be completely without risk. When introducing a new technology or recommending a treatment to a patient, clinicians are constantly weighing the potential risks and benefits.
The Montana bill states that “the mRNA vaccines have caused enormous numbers of deaths, disabilities, and serious adverse events.” The large amount of research that’s been done on these vaccines since they were developed does not support this assertion.
Because so many doses of these vaccines were administered in an effort to bring the COVID pandemic under control, scientists have lots of data to work with when analyzing how they have performed. In the first six months of their release, a staggering 298 million doses of the Pfizer-BioNTech and Moderna vaccines were given in the US.
A study published in 2022 found that between December 2020 and June 2021, a little over 340,500 adverse events were reported to the Vaccine Adverse Event Reporting System (VAERS). Of these, 92 percent were deemed mild, including things like headaches and pain at the injection site. Of the small minority who experienced more serious effects, most recovered fully.
Other studies have looked at specific groups of people or different virus variants. A paper published in 2024 concluded that the benefits of mRNA vaccines outweighed the risks in children aged 6 months to 4 years. A 2023 study in the American Journal of Epidemiology concluded, “The benefits of mRNA COVID-19 vaccines in protecting against the omicron variant outweigh the risks, irrespective of age, sex, and comorbidity.”
It’s on the strength of the evidence that the Centers for Disease Control and Prevention (CDC), continues to recommend mRNA COVID vaccinations for everyone aged 6 months and older.
During the debate over House bill 371, opposition came from state medical officer Douglas Harrington, among others. As well as pointing out the inaccuracies we’ve explored here, Harrington told the committee that the bill could needlessly curtail progress towards treating other key diseases, “like tuberculosis, malaria, zika, [and] the rapidly mutating influenza viruses.”
NBC Montana also points to a legal review note saying the bill could be in violation of the US Constitution’s supremacy clause, meaning that that this kind of legislation may not be within the purview of individual states at all.
