Scientists said once the virus targeted the cancer, it replicated itself, making its effects even more powerful.

Prof Hardev Pandha, Principal Investigator of the study and Professor of Medical Oncology at the University of Surrey, said: “We are very excited about it. The virus gets into the cancer and replicates, like a little factory of viruses. It heats up the tumour environment, and is very specific in targeting the cancer – it had the least toxicity I have seen for years.”

It comes as other trials examine the role of common cold viruses to treat a range of cancers, including breast, bowel, lung and skin diseases.

Prov Pandha said: “It’s almost like a universal agent – once it gets in it kills the cancer. It could be combined with lots of other treatments.”

He said the use of the virus could help “revolutionise” treatment for the disease.

The study, with Royal Surrey County Hospital, involved patients non-muscle invasive bladder cancer, which is found in the tissue of the inner surface of the bladder.

The virus was found to have infected cancerous cells and replicated itself causing the cells to rupture and die.

And urine samples taken from patients after the treatment detected “shedding” from the virus – indicating that once virally infected cancer cells had died, the newly replicated virus continued to attack more cancerous cells.

“Reduction of tumour burden and increased cancer cell death was observed in all patients and removed all trace of the disease in one patient following just one week of treatment, showing its potential effectiveness. Notably, no significant side effects were observed in any patient,” the research found.

Scientists said the success of the trials was particularly significant because current treatments for the disease have limited success.

Transurethral resection, an invasive procedure that removes all visible lesions, has a high chance of disease recurrence, with rates ranging from 50 per cent to 70 per cent.

Dr Nicola Annels, Research Fellow at the University of Surrey, said: “Traditionally viruses have been associated with illness – however in the right situation they can improve our overall health and wellbeing by destroying cancerous cells.”

Dr Mark Linch, from Cancer Research UK, said: “Although at an early stage, these initial results are encouraging. It will be really interesting to see how this new virus-based therapy fares in larger trials in people with non-muscle invasive bladder cancer, particularly in combination with newer immunotherapies.”