A common infection contracted through oral sex may account for anything between 20-60% of cases of mouth and throat cancers according to Cancer Research UK. However, despite numerous studies which suggest a strong link, the public remains largely unaware of the relationship between oral sex and these cancers.

Oral cancers affect almost 5,500 people and kills around 1,800 in the UK every year. The figures have risen dramatically of late, with the rates of these cancers rising by 50% in men since 1989 and by a rise of 3% in women each year. They mainly affect people in their forties and fifties.

In the past, cancer charities have cited the main causes of throat and mouth cancer as being excessive consumption of cigarettes and alcohol. Indeed when these two risk factors are considered, the chance of developing oral cancers are increased by 20% compared to people not consuming cigarettes or alcohol.

Jessica Harris, a health information officer for Cancer Research UK, explains that while these behaviors are still considered very influential in developing oral cancers, findings by Cancer Research UK in recent years has shown that the human papilloma virus (HPV), an extremely common infection, may be a major cause too.

“Some studies which have been published recently show that the more oral sex partners people have, the higher the risk of some types of mouth and throat cancers. This is because of HPV, which is the same infection which increases the risk of cervical cancer,” Harris says.

Despite the fact that a vaccine for HPV has been administered to 12 and 13-year-old girls in the UK since 2008, Cancer Research UK say that it is unclear as to whether the same vaccine could protect against other types of cancer as well.

According to Harris the problem is that at the moment no-one is sure of the exact details of the link between HPV and mouth and throat cancers.

“We don’t really understand the relationship between the infection and a cancer. Add to that we don’t really understand the way HPV behaves in the throat and mouth and we don’t know how it’s transmitted or how to reduce the risk. Because of all that, there’s a lot more research which needs to be done.”

At the moment, although Cancer Research UK recognises the link between oral cancers and HPV, they are unsure of ways in which transmission of the infection can be avoided.

However Harris says that advice from the NHS is to use protection during oral sex by using either a condom or dental dam. Though it is unclear whether this will protect against HPV, this is currently the best advice available.