Girls aged 12 to 13 have been given the human papillomavirus (HPV) vaccine since the introduction of a national vaccination programme four years ago, with many thousands on the scheme.
But what about boys? With HPV now conclusively linked to the development of oral cancers, and up to 90 per cent of anal cancers, is it time to start protecting them too?
Universal vaccination is now recommended by many experts and countries including Australia, the US and certain regions of Canada have expanded their vaccination programmes to include both boys and girls.
In a recent opinion piece in the British Medical Journal, a lecturer in chronic illnesses at Queen's University Belfast, argued the case for vaccination in boys.
According to Dr Gillian Prue, HPV-related disease in men "is associated with considerable burden" and "vaccinating boys is likely to produce health and economic benefits". She also said that a recent study of more than 4,000 males aged between 16 and 25 had found that the HPV vaccine prevented genital warts as well as penile and anal cancer.
Dr Prue says vaccinated boys would be protected against non-vaccinated girls and other men, and would not have the potential to infect girls.
The National Immunisation Advisory Committee (NIAC) guidelines from 2013 give a permissive recommendation, meaning they can get the HPV vaccine if they want, but it isn't yet recommended as part of a national programme.
It advises that the vaccine may be given to males from nine to 26 years and should be considered for men who have sex with men, those who are HIV positive, and those who have had haematopoietic stem-cell transplants.
For girls, two doses rather than the original three are recommended as of this month. This should reduce the overall cost of the vaccination programme.
According to Dr Kevin Connolly, the chairman of the NIAC, the committee has seen the recent publications relating to vaccination of boys and stresses that the topic is on the draft agenda for its next meeting, in September.
“It is likely that a new health-technology assessment will be necessary, as the high uptake rates in girls and the change to a two-dose schedule will affect the cost-effectiveness,” he said.
Dr Jack Lambert, consultant in infectious diseases at the Mater Hospital, explains that when the HPV vaccine was introduced it was focused on the prevention of cervical cancer, and so the main target was women.
This meant that cost-benefit analyses focused initially on the importance of preventing cervical cancer, and the cost of screening and treatment versus the cost of vaccination of all girls, he said.
“It is obvious, however, that these HPV infections come from sexual exposure to men and boys, and it is also more common for men and boys to have more sexual partners than [it is for] women,” said Dr Lambert. “There are also clear benefits of giving the vaccine to both men and women to prevent genital warts.”
The current focus on men who have sex with men is a bit short-sighted, as heterosexual men also have a considerable burden of HPV, says Dr Lambert.
“It is thought that HPV vaccinations may prevent many different cancers, not just cervical cancer, in the future. This argues in favour of vaccination of both boys and girls, independent of their perceived short-term risk, as early as possible before sexual debut.”
Dr Connolly is quick to highlight the success of the vaccination programme for girls four years after its introduction.
“The uptake of the HPV vaccine in girls aged 12 to 13 has exceeded its target rate of 80 per cent, as has the uptake in the catch-up programme in sixth-year girls, which had a target of 60 per cent. These uptake rates are among the highest in the world,” he says.
HPV – the facts
HPV is a group of more than 100 viruses, of which about 40 can infect the genital tract.
It is the most common STI worldwide, with about 80 per cent of sexually active people being infected by the age of 50.
The disease spectrum can range from asymptomatic infection to benign genital warts and invasive cancer.
Ano-genital warts accounted for 19.4 per cent of all sexually transmitted infection notifications in Ireland in 2011.
HPV is responsible for 5.2 per cent of the cancer burden worldwide.
High-risk HPV types are responsible for about 90 per cent of anal cancers, 65 per cent of vaginal cancers, 60 per cent of oropharyngeal cancers, 50 per cent of vulvar cancers and 35 per cent of penile cancers.
Cervical cancer is the second most common cancer in women worldwide, with an estimated 530,000 new cases in 2008 and 275,000 deaths in the same year.
Source: Immunisation Guidelines for Ireland 2013, NIAC
