PARIS, France (AFP) — A novel vaccine temporarily shielded lab monkeys from Ebola, and a booster jab provided lasting protection, according to a study Sunday that endorsed approval for tests on humans.

A single shot of the vaccine, based on a cold virus that affects chimps, gave macaques “complete short-term and partial long-term protection” from the deadly virus, researchers reported in the journal Nature Medicine.

Animals that received a booster shot developed “durable” immunity.

If approved, “this vaccine will be beneficial for populations at acute risk during natural outbreaks or others with a potential risk of occupational exposure”, said the study’s authors.

They claimed to be the first to demonstrate a vaccine with “durable protection” against Zaire Ebola virus, which has killed 1,841 of the 3,685 people infected in Guinea, Liberia and Sierra Leone, according to World Health Organisation (WHO) numbers.

Nancy Sullivan of NIAID’s Vaccine Research Centre led a team that developed the vaccine based on a type of chimpanzee virus dubbed ChAd3.

The virus is used as a carrier, or vector, to deliver snippets of Ebola DNA into human cells.

The genetic material is non-infectious, but stimulates the cells of the vaccine recipient to recognise Ebola and mount an immune response against it.

The early trials in humans are the first phase in a three-step vetting process.

They will be carried out among healthy adults not infected with the Ebola virus to determine if it is safe and induces an adequate immune response.