Rosa Rubicondior: Bearing False Witness - Why the American Religious Right Are Lying Again.

The MMR vaccine doesn’t contain ‘aborted fetus debris’, as RFK Jr has claimed. Here’s the science

In recent years, vaccine misinformation has become an all-too-familiar feature of public discourse, often amplified by prominent figures with political or ideological agendas. One of the more persistent myths involves the claim that the MMR (measles, mumps, and rubella) vaccine contains material derived from aborted foetuses—a claim most recently repeated by Robert F. Kennedy Jr., a leading voice in the anti-vaccine movement.

In the article below, reproduced with permission under a Creative Commons licence, Professor Hassan Vally—a public health expert and epidemiologist—carefully and comprehensively dismantles this falsehood. Writing for *The Conversation*, he draws on decades of scientific research and vaccine development history to explain precisely why this claim is misleading, how vaccines are actually made, and why they remain one of the safest and most effective tools in modern medicine.

This piece is a timely and important correction to the misinformation circulating in some circles, particularly those aligned with religious or ideological opposition to vaccination. For readers unfamiliar with the scientific details, Professor Vally’s article offers a clear and accessible summary grounded in evidence and public health best practice.

First, an AI analysis of the reasons Kennedy and his far-right religious allies are deliberately misleading the American public and casually risking the lives of American children with a characteristic callous disregard for the children who will inevitably and predictably die as a result of this disinformation:

What are some of the reasons the religious right in the USA would want to mislead the American public about MMR vaccines? The religious right in the United States has played a significant role in disseminating misinformation about vaccines, including the MMR (measles, mumps, and rubella) vaccine. This trend is driven by a combination of theological, ethical, political, and cultural factors that align with broader conservative agendas.

Religious and Ethical Concerns
A primary objection among some religious conservatives pertains to the use of foetal cell lines in vaccine development [1,3,4,5,6,7,8]. Specifically, the rubella component of the MMR vaccine was developed using a human cell line derived from an elective abortion performed in the 1960s. Although the final vaccine product does not contain foetal tissue, this association has led to moral objections from certain groups who view any connection to abortion as ethically unacceptable [9,10].
Emphasis on Parental Rights and Individual Liberties
The religious right often champions parental authority and individual freedoms, opposing what they perceive as governmental overreach. This perspective fuels resistance to vaccine mandates, framing them as infringements on personal liberties and parental rights to make medical decisions for their children .
Political Polarization and Distrust of Institutions
Vaccine skepticism has increasingly aligned with conservative political ideologies. Figures like Robert F. Kennedy Jr. have propagated vaccine misinformation, which resonates with segments of the religious right that harbour distrust toward federal health agencies and scientific authorities . This skepticism is often rooted in broader political narratives that question the legitimacy and intentions of governmental institutions.
Influence of Anti-Vaccine Activists
Prominent anti-vaccine activists, such as Del Bigtree, have targeted religious communities to spread misinformation. By leveraging religious language and values, they have effectively sown doubt about vaccine safety and efficacy, further entrenching vaccine hesitancy within these groups [11].
Cultural Identity and Community Cohesion
For some religious communities, vaccine refusal is intertwined with cultural identity and a desire to maintain community cohesion. In certain cases, skepticism toward vaccines is less about theological doctrine and more about preserving traditional lifestyles and resisting external influences perceived as threats to communal values [12].
Conclusion
The dissemination of vaccine misinformation by the religious right in the U.S. is a multifaceted issue, rooted in ethical concerns, political ideologies, and cultural identities. Addressing this challenge requires nuanced engagement that respects religious beliefs while promoting accurate scientific information and public health initiatives.

The MMR vaccine doesn’t contain ‘aborted fetus debris’, as RFK Jr has claimed. Here’s the science

Hassan Vally, Deakin University

Robert F. Kennedy Jr, the United States’ top public health official, recently claimed some religious groups avoid the measles, mumps and rubella (MMR) vaccine because it contains “aborted fetus debris” and “DNA particles”.

RFK Jr on measles: "The MMR vaccine contains a lot of aborted fetus debris." pic.twitter.com/wq7S3xssl7
— Aaron Rupar (@atrupar) May 1, 2025

The US is facing its worst measles outbreaks in years with nearly 900 cases across the country and active outbreaks in several states.

At the same time, Kennedy, secretary of the Department of Health and Human Services, continues to erode trust in vaccines.

So what can we make of his latest claims?

There’s no fetal debris in the MMR vaccine

Kennedy said “aborted fetus debris” in MMR vaccines is the reason many religious people refuse vaccination. He referred specifically to the Mennonites in Texas, a deeply religious community, who have been among the hardest hit by the current measles outbreaks.

Many vaccines work by using a small amount of an attenuated (weakened) form of a virus, or in the case of the MMR vaccine, attenuated forms of the viruses that cause measles, mumps and rubella. This gives the immune system a safe opportunity to learn how to recognise and respond to these viruses.

As a result, if a person is later exposed to the actual infection, their immune system can react swiftly and effectively, preventing serious illness.

Kennedy’s claim about fetal debris specifically refers to the rubella component of the MMR vaccine. The rubella virus is generally grown in a human cell line known as WI-38, which was originally derived from lung tissue of a single elective abortion in the 1960s. This cell line has been used for decades, and no new fetal tissue has been used since.

Certain vaccines for other diseases, such as chickenpox, hepatitis A and rabies, have also been made by growing the viruses in fetal cells.

These cells are used not because of their origin, but because they provide a stable, safe and reliable environment for growing the attenuated virus. They serve only as a growth medium for the virus and they are not part of the final product.

You might think of the cells as virus-producing factories. Once the virus is grown, it’s extracted and purified as part of a rigorous process to meet strict safety and quality standards. What remains in the final vaccine is the virus itself and stabilising agents, but not human cells, nor fetal tissue.

So claims about “fetal debris” in the vaccine are false.

It’s also worth noting the world’s major religions permit the use of vaccines developed from cells originally derived from fetal tissue when there are no alternative products available.

Are there fragments of DNA in the MMR vaccine?

Kennedy claimed the Mennonites’ reluctance to vaccinate stems from “religious objections” to what he described as “a lot of aborted fetus debris and DNA particles” in the MMR vaccine.

The latter claim, about the vaccine containing DNA particles, is technically true. Trace amounts of DNA fragments from the human cell lines used to produce the rubella component of the MMR vaccine may remain even after purification.

However, with this claim, there’s an implication these fragments pose a health risk. This is false.

Any DNA that may be present in this vaccine exists in extremely small amounts, is highly fragmented and degraded, and is biologically inert – that is, it cannot cause harm.

Even if, hypothetically, intact DNA were present in the vaccine (which it’s not), it would not have the capacity to cause harm. One common (but unfounded) concern is that foreign DNA could integrate with a person’s own DNA, and alter their genome.

Introducing DNA into human cells in a way that leads to integration is very difficult. Even when scientists are deliberately trying to do this, for example, in gene therapy, it requires precise tools, special viral delivery systems and controlled conditions.

It’s also important to remember our bodies are exposed to foreign DNA constantly, through food, bacteria and even our own microbiome. Our immune system routinely digests and disposes of this material without incorporating it into our genome.

#Measles can lead to severe, long-term complications and can even cause your immune system to forget how to resist infections.

♦️Brain damage
♦️Severe diarrhoea and dehydration
♦️Deafness
♦️Blindness
♦️Pneumonia

Two doses of the measles vaccine is the only way to prevent… pic.twitter.com/cIDxI8q0Lh
— World Health Organization (WHO) (@WHO) March 31, 2025

This question has been extensively studied over decades. Multiple health authorities, including Australia’s Therapeutic Goods Administration, have addressed the misinformation regarding perceived harm from residual DNA in vaccines.

Ultimately, the idea that fragmented DNA in a vaccine could cause genetic harm is false.

The bottom line

Despite what Kennedy would have you believe, there’s no fetal debris in the MMR vaccine, and the trace amounts of DNA fragments that may remain pose no health risk.

What the evidence does show, however, is that vaccines like the MMR vaccine offer excellent protection against deadly and preventable diseases, and have saved millions of lives around the world.
Hassan Vally, Associate Professor, Epidemiology, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Published by The Conversation.
Open access. (CC BY 4.0)

Robert F. Kennedy Jr.'s repeated misrepresentations about the MMR vaccine, particularly the false claim that it contains "aborted fetus debris," are not only scientifically unfounded but socially irresponsible. These assertions fuel distrust in public health systems, endanger vulnerable populations, and contribute to the resurgence of preventable diseases such as measles—now once again circulating in parts of the United States and Europe where vaccination rates have declined.

Such misinformation is especially damaging when it intersects with ideological movements, including sectors of the religious right, where ethical concerns around abortion are cynically exploited to stoke fear and resistance. As Professor Hassan Vally has shown, the reality of vaccine science is clear, consistent, and well-documented: the MMR vaccine is safe, effective, and vital for preventing serious illness and death.

Ultimately, combating these dangerous falsehoods requires more than just setting the scientific record straight. It demands a concerted effort to promote health literacy, rebuild trust in institutions, and expose the motives—political, financial, or ideological—behind those who seek to undermine public confidence in vaccines. In a world where misinformation spreads faster than facts, the stakes could not be higher.

Kennedy's deliberate misinformation for blatantly political motives illustrates how religion can provide excuses for people who need excuses. As ever the main beneficiaries of the opportunities that religion presents are from the political right where honesty and personal integrity as seen as character flaws and weaknesses to be exploited.

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