One in every six cancer cases is caused by infectious diseases, according a global study published in the Lancet Oncology review.
The study's French researchers looked at data on 27 cancers from 184 counties, and attributed 1.9 million cancer cases to four main infections: human papillomavirus (HPV), hepatitis B and C, and the ulcer-inducing Helicobacter pylori.
According to the BBC, nearly one-third of the cancer cases affected people 50 years or younger. Cervical cancer, which is predominantly caused by HPV, accounted for about half of all infection-related cancers in women, while 80 percent of cancers diagnosed in men were liver and gastric cancers.
The study authors also estimated that 1.5 million of the 7.5 million cancer deaths worldwide in 2008 were related to infectious diseases. HPV and hepatitis B infections are largely preventable through vaccination, and H. pylori can be treated with antibiotics.