Politician Evan Harris was today becoming the first person to be injected with a new Aids vaccine, writes Victoria Owen.

The Oxford West and Abingdon MP is one of 18 human guinea pigs taking part in the ground-breaking research at the Institute of Molecular Medicine, on the John Radcliffe Hospital site in Headington,

Led by immunology specialist Professor Andrew McMichael, the Medical Research Council-funded study could eventually be used to end the Aids epidemic plaguing Africa.

Dr Harris, a former junior doctor at the JR, has a dual interest in the research.

As a Liberal Democrat, he started his parliamentary career responsible for health issues including HIV and Aids.

And his parents both doctors worked in South Africa, but left shortly before he was born because they were opposed to the regime of apartheid.

Now Dr Harris hopes he can play a small part in the fight against the growing crisis on the African continent, which is home to 70 per cent of the world's 33 million HIV victims. "I'm pleased to be able to be involved in such an important trial. I'm confident that the vaccine is safe, and that the vaccine will prime the immune system to be able to protect against HIV infection.

"I'm taking part in this trial as I believe that finding an effective vaccine is our best hope to control this devastating disease."

While previous attempts to design a vaccine have focused on the B-strain of the virus, which is prevalent in Europe and the United States, the Oxford research is the first to focus on the A-strain, which dominates Africa.

Although it contains DNA from the Aids virus, there is no chance of volunteers being infected.

The genetic ingredient used is the part which tells the virus to stimulate strong immune responses. In turn, body cells are instructed to gear up for an attack from infection. Dr Harris said: "It is not risky at all. It is designed to prevent the infection, so if anything I will be safer than anyone else.

"And the volunteers will not be challenged with HIV after being given the vaccine. This is just a standard safety trial to see if it is safe to use."

Prof McMichael, working in partnership with a team from the University of Nairobi, came across the idea after studying prostitutes in the Kenyan city.

Although the women are constantly exposed to HIV a small minority of them have defied the infection for many years. And the trial today is the latest step in a collaboration which has already taken several years of research.

Prof McMichael said: "We're very pleased that after much careful preparation the trial can begin in earnest. ''

The trials will be held at the John Warin ward, at the Churchill Hospital, Headington and will be followed by similar safety checks in Nairobi in three to six months. If both sets prove successful, the scientists will be start a second phase, using a larger group of volunteers.

The end result which could still be years away could provide African communities with an efficient vaccine.

And this prospect has excited campaign groups across the world, who are all waiting to see if the Oxford vaccine is the answer to the Aids and HIV problems in Africa.

Dr Seth Berkely, President of the International Aids Vaccine Initiative, said: "This is the first of four vaccine candidates for Africa our organisation is moving forward. Vaccine development has traditionally relied on the altruism of volunteers. "This is especially true of the Oxford trial, since the vaccine was designed to target strains most prevalent in Africa. Volunteers are the true heroes of this endeavour."

The researchers are still looking for healthy volunteers to help with the trials in Oxford.

Anyone who is interested can call the information lines on 0800 169 6978 or 07811 068873.