Image: Screenshot YouTube, Sun News

By Amy Lupica, ODP Contributing Writer

Shark populations may be in danger as countries race to develop a COVID-19 vaccine. Conservationists fear that the demand for a cheap and accessible source of squalene, a common vaccine ingredient produced by shark livers, could lead to the killing of 500,000 sharks. As sharks are already threatened by overfishing often killed only for their fins, conservationists believe that a mass killing of sharks will further harm suffering shark populations and ecosystems. Activists criticize vaccine companies for choosing the cheapest, and potentially most ecologically destructive, method of obtaining squalene, citing the many other sources available.

Why This Matters: Sharks are under attack across the globe. Overfishing and habitat loss have left 143 different shark species considered “endangered,” “critically endangered,” “near threatened,” or “vulnerable.” Sharks are often hunted for delicacies like shark fin soup or for “traditional” medicine. Approximately 100 million sharks are killed each year for trade; 3 million a year are killed to obtain squalene for medical use. Conservationists say that adding another half-million to that number would be devastating for ecosystems across the globe, especially coral reefs, which have seen a massive decline in shark populations in recent years.

What Is Squalene?

Squalene is used in vaccines as an adjuvant to aid in the immune response necessary for the vaccine to be effective. The World Health Organization reported that of the 176 global vaccines in development and trial, 17 are reliant on squalene, and according to the non-profit organization Shark Allies, 5 of those rely specifically on shark liver oil. It takes the livers of about 3,000 sharks to produce one ton of squalene. One vaccine in development would include 9.75 milligrams per dose, an amount that experts estimate would require 249,351 sharks to provide one dose to every person on Earth. If two doses are required to achieve immunity, as some experts predict, that number rises to half a million. Conservationists also worry that, without a more sustainable source of squalene, vaccine production could face obstacles in the future.

Sharks are not the only source of squalene. Shark Allies says that squalene is “not a unique or ‘magical’ ingredient,” citing non-animal alternatives like “yeast, olive oil, bacteria, and possible algae” as viable sources. Some companies have even extracted squalene from sugarcane. In 2015, a team of researchers was able to synthesize squalene in a lab using genetically engineered bacteria. Conservationists say that corporations have been reluctant to adopt these sustainable sources because they are about 30% more expensive than the harvesting of squalene from sharks. They also take more time; Shark Allies reports that it takes about 70 hours to extract squalene from olive oil, compared to just 10 hours from shark livers.

Stefanie Brendl, founder of Shark Allies, emphasizes that conservationists aren’t against the development of a COVID-19 vaccine; they simply want companies to use sustainable sources of squalene to avoid damaging ecosystems and hindering vaccine progress in the future. Brendl emphasizes, “A reliance on shark oil for a global vaccine—it’s truly insane. A wild animal is not a reliable source and cannot sustain ongoing commercial pressure. [And] the overfishing of sharks globally is already at critical levels.”