The first major trials for a vaccine against the deadly Ebola virus are set to begin in the Western African country of Liberia today (Monday 2 February).

Scientists will give the vaccine to some 30,000 volunteers in a bid to put a halt to the ever increasing number of people who have already lost their lives to the virus. Over 8,500 people have succumb to the disease already.

The trial will involve the volunteers being injected with a small amount of the virus, which scientists hope will trigger production of an immune response. It is unclear however how effective this method could be.

Liberia has been one of the worst affected nations in the latest bout against the illness, with the country having lost more than 3,600 people to the disease. However, this has slowed down dramatically in recent months.

The trial conducted at Oxford University's Jenner Institute saw a total of 60 healthy volunteers inoculated with a modified chimpanzee cold virus – a vaccine jointly developed by GlaxoSmithKline and the US National Institutes of Health.

In those tests adverse events reported by the volunteers were mild, such as moderate fever which passed in a day.

The immune responses observed in the vaccine recipients were less than those seen in monkeys that were protected from experimental Ebola virus infection.

The antibody response seen was weaker than that from a US study which tested a significantly higher dose of the same vaccine.

It is still not fully clear what degree of immunity humans require for protection from the virus. Larger trials like the one in West Africa are expected to throw more light.