According to a new study, about a sixth of all cancers or about two million a year globally are caused by infections that are mostly treatable or preventable.

The Lancet Infectious Diseases review studied incidence rates for 27 cancers in 184 countries and found that four main infections were responsible for the disease. It found that the infections, human papillomaviruses, Helicobacter pylori and hepatitis B and C viruses caused 1.9 million cases of cervical, gut and liver cancers.

The study said that most of these cancers were in the developing world. A team of researchers from the International Agency for Research on Cancer in France pointed out that steps should be taken to address the issue and the disease must be defined as a communicable disease.

The researchers found that the proportion of infection related cancers were times higher in some parts of the developing world like East Asia, which was 22.9 per cent when compared to developed countries like the UK, where it was at 7.4 per cent. They said that about a third of cases occur in people younger than 50 years.

Drs Catherine de Martel and Martyn Plummer, who led the research, said, "Infections with certain viruses, bacteria, and parasites are some of the biggest and preventable causes of cancer worldwide. Application of existing public-health methods for infection prevention, such as vaccination, safer injection practice, or antimicrobial treatments, could have a substantial effect on the future burden of cancer worldwide."