The Oxford Covid vaccine was estimated to have saved six million lives in the first year it was used around the world and hundreds of millions of doses have been taken.

However, the vaccine was also restricted for use in some countries because of rare blood clots which affected up to one in 100,000 people.

It is possible this vaccine carries the same risk, although this is much lower than the threat from the Bundibugyo species of Ebola which kills around a third of those infected.

Pollock said severe side effects are “very rare” and they thought “very deeply” about the implications for trials on healthy people, and that any risk would be communicated to volunteers.

“I want to stress that the Covid AstraZeneca vaccine was given to millions of people safely,” she added.

There are three other vaccines being developed for the Bundibugyo species of Ebola.

These include one from biotechnology company Moderna using their mRNA vaccine technology. The International Aids Vaccine Initiative and Public Health Vaccines, based out of the US, are using the same technique that has been proven to work for another species of Ebola, but is slower to manufacture.