Vaccinating against the virus that causes glandular fever could prevent up to 200,000 cases of cancer worldwide each year, according to a leading charity.
More work is needed to develop a vaccine against Epstein-Barr Virus (EBV), which is linked to a number of cancers including lymphoma, said Cancer Research UK.
Research funded by the charity led to the identification of the virus and its association with cancer 50 years ago.
Speaking on the anniversary of the discovery, Cancer Research UK scientist Professor Alan Rickinson, from the University of Birmingham, said: "We now know so much about how the virus contributes to the development of.. particular types of cancer.
"The next big challenge is to develop a vaccine that will prevent infection by the virus.
"We believe that a successful EBV vaccine could prevent up to 200,000 new cases of cancers per year."
Around 95% of the global adult population is infected with EBV. Many people pick up the virus in childhood and carry it for life with no ill effects.
Others infected as teenagers may develop glandular fever but make a full recovery - but in some individuals the virus can trigger cancer.
The most common cancer associated with EBV in the UK is the blood disease Hodgkin lymphoma, as well as a different form of lymphoma common in transplant patients.
Burkitt lymphoma, gastric carcinoma, and the nasal tumour nasopharyngeal carcinoma are other cancers linked to the virus.
Around one in 10 gastric, or stomach, tumours contain high levels of EBV.
In total EBV is believed to be responsible for an estimated 0.4% of all cancers in the UK each year, leading to 1,200 diagnosed cases in 2010.
Dr Graham Taylor, another Cancer Research UK-funded scientist also based at the University of Birmingham, said: "We know that it's possible to make a vaccine to prevent certain types of virus-associated cancer developing.
"Vaccination against human papillomavirus (HPV), the virus linked to cervical cancer in women, is a shining example.
"EBV is a different type of virus and is transmitted in a different way. But the basic principle remains the same. For EBV, we now need to develop the science that can turn that principle into a reality."
Nell Barrie, senior science information manager at Cancer Research UK, said: "The past 50 years of research has been an exciting journey, from the discovery of the virus to gathering the proof that EBV plays a key role in several cancers and an understanding of how the virus does this.
"Thanks to all this research, we're moving closer towards the goal of being able to prevent EBV infection with a vaccination, potentially stopping many children and adults around the world from developing cancer."
EBV takes its name from Sir Anthony Epstein and his research assistant Dr Yvonne Barr, who discovered the virus in 1964 while working at London's Middlesex Hospital.
A national conference is taking place in Oxford this week to mark the discovery's anniversary.