New STI statistics published by Public Health England show that the number of HPV diagnoses has fallen significantly since the introduction of the HPV vaccine in 2008.
Because HPV (the human papillomavirus) is responsible for over 99% of cervical cancer cases, experts are confident that the vaccine could lead to a virtual eradication of the disease.
Recently there have been calls for the vaccine, offered to girls aged 12-18 by the NHS, to be offered to boys as well.
How far have HPV diagnoses fallen?
Public Health England release STI statistics in June each year.
- Between 2009 and 2017, they observed an 89% decline in first-episode cases of genital warts in 15-17 year old girls; and a 70% decline in boys in the same age range.
- From 2010 to 2016, HPV infections overall fell by 86% in women aged 16-21.
The HPV vaccine was brought into widespread use in the UK in 2008. With the implementation of the National HPV Immunisation Programme, it’s estimated that around four in every five young people in the UK have received the vaccination since it become available.
Would boys benefit from vaccination too?
HPV is a cause of male cancers as well, such as anal, mouth and throat cancer; so there is currently a debate around whether the vaccination should be rolled out to boys.
As of 2017, the vaccination is now offered to men who have sex with men aged between 16 and 45, but it is not currently offered to boys; the decline in 15-17 year old male cases above has been attributed to fewer instances of the virus being passed on to them from females.
However, because it has been so effective, some experts are now recommending that the vaccination should be made available to boys too.
Professor Mark Lawler, who specialises in Cancer Research and Cell Biology at Queen’s University in Belfast, told the BBC that although some boys would be protected with more girls being vaccinated, they may still be at risk in areas where uptake is low. He also made the case that the vaccination is routinely offered to boys in Canada and other countries.
What is HPV?
There are thought to be over 100 strains of the human papillomavirus. Around 40 of these affect the genitals and reproductive system in particular.
Lower risk strains of the virus can cause genital warts; whereas some higher risk strains can lead to cervical cancer. Some types of HPV, on the other hand, don’t cause any symptoms at all, and the body usually clears these strains of the infection on its own.
The virus can be transmitted through close skin contact, most typically through vaginal or anal sex. It can also be passed on through oral sex.
What does the virus do?
In short, HPV causes skin cells to divide and multiply at a faster rate. For some strains, this can lead to the appearance of small, flesh-coloured growths on the skin (genital warts). In higher risk strains, this cell division can speed up to a point where cell DNA can become damaged and eventually mutate; leading to cervical cancer.
HPV can also cause cancer in other parts of the body, such as the anus, mouth and throat; meaning that men can develop cancer if they’ve been infected with a cancer-causing strain of HPV too.
HPV is very common. Cancer Research state that around 80% of people will be infected with the virus at some stage throughout their lives (although the majority of these will be symptomless and self-limiting).
There are reported, by Cancer Research, to be over 3,000 cases of cervical cancer in the UK annually. Cervical screening (which is currently recommended every three years to all women aged between 25 and 64) is thought to prevent more than 2,000 deaths from cervical cancer on a yearly basis.
How does the HPV vaccine work?
Vaccines essentially work by encouraging the body to develop a defence against a particular virus or bacteria. The introduction of a very small amount of the infecting agent enables the immune system to become familiar with it, and produce antibodies capable of fighting the infection off. So, when someone comes into contact with the virus or bacteria after immunisation, their immune system is better able to deal with it.
There are two types of vaccine: attenuated (or ‘live’) and inactivated:
- live vaccines contain a very small number of active viral or bacterial cells, which typically have been replicated several times in a lab to reduce their potency;
- whereas in inactive vaccines, the virus or bacteria may have been ‘killed’ through chemical treatment or being subjected to high temperatures. The viral cells are then unable to multiply and spread.
The HPV vaccine is an inactive vaccination.
It isn’t known for certain exactly how long the HPV vaccine remains effective for, although it is thought to be a minimum of 10 years.
The vaccine currently offered, Gardasil, is effective against four strains of HPV (6, 11, 16 and 18). 6 and 11 are associated with most instances of genital warts; where as 16 and 18 are thought to be responsible for around 70% of cervical cancer cases.
Gardasil doesn’t completely eliminate the risk of cancer, as other HPV strains can cause it; so screening is still advised, even for those who have been vaccinated.
Who can have the HPV vaccine?
Currently, the HPV vaccine is offered for free by the NHS to girls aged over 12 and up to the age of 18. The first dose is typically given at age 12 or 13, and then a second dose is given six months subsequently. When the vaccine is given in girls aged 15 or over, a third dose may be needed as the body isn’t as sensitive to it.
Men who have sex with men (MSM) aged between 16 and 45 can have the vaccination for free too. This is because they aren’t as likely to benefit from female immunisation, and as such their risk won’t be reduced.
Women who are 18 or over and straight men can still normally have the vaccine, but in most cases they won’t be able to get it for free.
Where can I get the HPV vaccine?
The National HPV Vaccination Programme has been rolled out across schools in the UK, so girls are typically offered it in year 8. Girls who have missed it can usually arrange to have the vaccination done at an alternative time, by talking to their school or to their GP.
For adults, the vaccination is offered in some GP surgeries and GUM clinics can also provide it. If you want to know more about the HPV vaccine and whether it might benefit you, speak to your GP.