Although the experiments have so far only been carried out in a lab, researchers at Lewis Katz School of Medicine at Temple University, are confident that within three years they will be able to start trials on humans.

British experts said the treatment would effectively ‘engineer the body to cure itself from the inside’ while charities said the breakthrough was 'very exciting.'

Crucially the human immune cells which were tested in the lab showed no alteration to any other parts of the genetic code. There have been fears that altering DNA could trigger a cascade of genetic breaks which would prove harmful or even lethal to humans.

“The fact that for the first time we have been able to completely eliminate segments of the viral genome in the laboratory demonstrates that we should be able to eliminate it in the human body,” said lead researcher Professor Kamel Khalili.