Britain's Catherine, Princess of Wales, announced her cancer diagnosis, on March 22, 2024. ( AFP / OLI SCARFF)

Posts falsely link Covid vaccine to cancer after Kate Middleton reveals diagnosis

Experts have reiterated that there is no evidence linking cancer with Covid-19 vaccination, contrary to false claims that circulated on social media after Kate Middleton revealed she had been diagnosed with the disease aged just 42. An increase in the recorded rates of cancer in young people has been observed since at least the early 1990s.

"Princess Kate has been diagnosed with cancer -- she very likely has Turbo Cancer, caused by her mRNA vaccination in 2021," reads a post shared on X, written in simplified Chinese.

The post quoted Canadian physician William Makis saying the Princess of Wales "has been diagnosed with Cancer -- there is a high probability she has Turbo Cancer, caused by Covid-19 mRNA Vaccines she took in 2021".

AFP has previously debunked misinformation about Covid-19 vaccines promoted by Makis here, here and here.

Screenshot of the false X post, taken on March 28, 2024

The false claim surfaced after Kate Middleton revealed in a video message that she was diagnosed with cancer and was undergoing preventive chemotherapy.

She has received an outpouring of global sympathy after her video message on March 22, 2024 sought to end a maelstrom of unfounded claims that circulated amid her months-long absence from public view.

Middleton announced on social media on May 29, 2021 that she received her first dose of a Covid-19 vaccine, but did not mention which type of vaccine she received (archived link).

The false claim has been shared globally in other languages, including English, French, Croatian Spanish, Thai and German.

'No evidence'

"There is no evidence that any vaccines cause cancer," the International Agency for Research on Cancer (IARC) -- the specialised cancer agency of the World Health Organization -- told AFP in an email on March 25, 2024 (archived link).

"Increasing trends in cancer in young persons were already observable before the Covid epidemic and associated vaccination campaigns," the IARC added.

Speaking to AFP in 2022, Maya Gutierrez, a specialist in medical oncology at France's Curie Institute, agreed that any implication of a link between Covid-19 vaccines and rising cancer rates had "no rational basis" (archived link).

"In terms of timing, it's far too short, it's impossible for a vaccination to cause phenomena like this, there are two inconsistencies in this discourse, on the mechanism and the timing," she said.

Research on the correlation between the risk of death and age -- based on data collected before the Covid-19 epidemic -- showed that the risk of cancer in young people had been increasing.

According to a report by the American Cancer Society published in January 2024, "young adults are the only age group for which an increase in the incidence of cancer had been observed between 1995 and 2020" (archived link).

A large study published in the journal BMJ Oncology in 2023 found that the rate of under-50s diagnosed with 29 common cancers surged by nearly 80 percent between 1990 and 2019 around the world (archived link). 

Oncologist Kimmie Ng from the Dana-Farber Cancer Institute said the Princess of Wales was "another concerning example of the rising rate of cancer among adults under the age of 50".

Multiple factors

Shivan Sivakumar, oncologist and researcher at the University of Birmingham, told AFP that the reason for rising cancer rates among those under 50 remains unknown: "I don't think we've managed to link anything. I've seen data that this has been happening for over 10-15 years, not just a spike in the last three or four years."

Lifestyle, and in particular tobacco and alcohol consumption, have been blamed by certain researchers, particularly concerning colorectal cancer in young adults, but also intestinal cancer (archived link).

Improved diagnosis also partly explains this increase: many of these cancers would not have been detected before the 2010s, before the age of 50.

As noted by this study published in JAMA (Journal of the American Medical Association) in August 2023, “cancer has traditionally been considered a disease of the elderly (defined as adults aged 50 and over) (archived link).

The same study listed the following causes for the rise in cases among young adults: "Rising incidence of obesity, changes in environmental exposure, such as smoke and oil, sleep problems, lack of physical activity, microbiota, and exposure to carcinogenic components."

The false posts claimed that Covid-19 vaccination would cause "turbo-cancers", which "grow rapidly" and could be "aggressive". They claim the genetic instructions provided by mRNA vaccines are the reason spike proteins exist, when in reality, the jabs teach a recipient's cells to make copies of the proteins.

AFP has debunked the misinformation about spike proteins in Covid vaccines previously here, here and here.

Other physicians have repeatedly told AFP that the benefits of Covid-19 vaccination outweigh the risks, in line with recommendations from the WHO (archived link).

The IARC said: "Covid-19 vaccine is recommended for cancer patients as they have a higher risk of getting Covid-related morbidities and complications."

This story was updated to clarify the false claim that the posts made about spike proteins.
April 8, 2024 This story was updated to clarify the false claim that the posts made about spike proteins.

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