The COVID-19 vaccines won’t lead to the deaths of a half million sharks

Could the battle to end the COVID-19 pandemic be jeopardizing the shark population?

That’s what one alarming — albeit misleading — claim shared on Facebook asserts. Hundreds of thousands of sharks are at risk of dying, says the Dec. 19, 2021, post featuring an image of a jumping shark, because of the way the vaccine is made.

"Half a million sharks could be killed to make the COVID-19 vaccine," text under the photo reads. "Once again, it’s the animal which has to make a sacrifice for humans."

The post, which we found on a Facebook page called "Unknown Facts," 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.)

Although the post doesn’t mention a specific vaccine or how COVID-19 vaccines are linked to shark deaths, it appears to be referring to an oil-based compound typically made from shark livers called squalene that is often used in the health and cosmetics industry.

Shark Allies, an advocacy group, in late 2020 issued a statement that seems to be the basis of this claim. The group said that 500,000 sharks could be potentially killed to meet the demand of mass producing a vaccine. The New York Times looked into that figure and was not able to substantiate it.

Squalene can help boost immunity and aid in skin hydration. It is found in plants and animals, including humans, but sharks are considered one of the best sources as they carry high amounts of the compound. Some vaccines, including the Fluad influenza vaccine approved in the U.S. for people 65 and older, use squalene as an adjuvant to help trigger a stronger immune response in the body, according to the Centers for Disease Control and Prevention. 

But of the 137 COVID-19 vaccines that have been in development globally during the pandemic, three listed squalene as an ingredient, according to the World Health Organization's vaccine tracker, but none of those have reached approval stages:

• The first was co-developed by Australian biotech company CSL and the University of Queensland. Development of the vaccine ended in December of 2020 after it was found it could cause a false positive on certain HIV tests.
• Following the end of its partnership with CSL, the University of Queensland continued with the development of its own COVID-19 vaccine containing squalene. That vaccine is still in the early clinical trial phase, and is nowhere near ready for mass production. 
• The third vaccine is being developed by Bavarian Nordic, a biotech company in Denmark. It is in its second phase of clinical trials and is set to start the third phase sometime in 2022. 

None of the vaccines that have been approved for use in the U.S. — Moderna, Pfizer or Johnson & Johnson — contain the compound. And of the nine that have been approved for use globally, so far none of them contain squalene as an adjuvant.

In its reporting on the Shark Allies claim, The New York Times noted that an estimated 63 million to 273 million sharks are already caught and killed by humans each year, and squalene is harvested from millions of them. 

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But the Times found that figuring out the number of sharks that would be needed to produce the squalene for a vaccine involved too many variables, including requiring that an overwhelming majority of the squalene-free COVID-19 vaccines would first need to fail before those containing the ingredient would even be in the mix. 

A Facebook post claimed that a half million sharks could be killed in order to make the COVID-19 vaccines.

Squalene is used in several vaccines to help elicit a stronger immune response in the body.

But the nine COVID-19 vaccines that have been approved for use across the globe do not contain the compound. Three of 137 vaccines in development worldwide for COVID-19 suggest using squalene as an ingredient, but only two of those have progressed in clinical trials and there is no guarantee they will be approved for use.

Finally, calculating the number of sharks it would take to produce a vaccine that uses squalene relies on too many variables to make the half million figure reliable.

We rate this claim as False.