There are fears that up to a million sharks could be killed in the race to produce a coronavirus vaccine.
Squalene, made from shark liver oil, is often used in vaccines to boost efficacy.
Shark Allies, a non-profit organisation dedicated to the conservation of sharks and rays, said using shark squalene would be "short-sighted", "unpredictable" and "unsustainable".
The campaign group has created an online petition for scientists to "stop using sharks in COVID-19 vaccine and use existing sustainable options" instead. Read more >>