Teenagers in Guernsey will only be given one HPV jab, instead of the two that were previously offered.

Associate Director of Public Health, Alex Hawkins-Drew tells Island FM why the change has been made.

"The UK's Joint Committee on Vaccination and Immunisation (JCVI) have looked at the long-term data on the efficacy of the vaccine, which is how well the jab works in the months after someone has received it.

They have also looked at the years after people received a dose as well and the evidence shows that it is safe and effective just have a single dose."

The vaccine protects people against the Human Papillomavirus, or HPV, which is a sexually transmitted disease.

But, Alex says that most people won't know they have it.

"A large majority of people will get a HPV infection at some point in their life, but they will just clear that naturally.

But there are some more high-risk variants of HPV virus and those can go on to cause cervical cancer in some people. The vaccine offers protection against cervical cancer but it also offers protection from other types of cancers."

The changed course will begin this school year, with children in Year 8 being offered the single dose.

Anyone who has started their course but hasn't yet received their second jab will automatically be consider fully vaccinated.