Lots of people know about the HPV vaccine and its importance to girls, but did you know it can also benefit boys? Dr Harriet Stuart-Clarke explains.
HPV, or Human papilloma virus, is a family of over 150 viruses called papillomaviradae which cause infections in humans. Different members of the papillomaviradae family, each denoted as a number, cause infections in different types of skin or mucous membrane. HPV-6 and HPV -11 cause up to 90 per cent of genital warts.
Fact – ‘Gardasil 9’ vaccine covers HPV 6, 11, 16, 18, 31, 33, 45, 52 and 58.
HPV is spread by genital-to-genital contact, penetrative and oral sex. People can contract HPV even if they only have one partner. A small percentage of people infected will become chronically infected and a proportion of those will get pre-cancerous changes which, given time, may progress to cancer. HPV- 16 and HPV-18 are responsible for 71 per cent of cervical cancer worldwide.
For this reason HPV-16 and HPV-18 were the first viruses to be targeted with a vaccine, approved in 2006.
Fact – the HPV vaccine was introduced in Australia for girls in 2007.
The rate of HPV in women aged 18-24 reduced from 22 per cent to 1 per cent when comparing 2005 to 2015.
Vaccination is targeted at children before they become sexually active. It can be given from the age of nine, but most people have it between 11 and 12 years of age. Two vaccines are given six months apart. Older children and adults (15 years or older) require a third vaccination as they have a less strong response.
So why would boys benefit?
Vaccinated women in countries like the UK, Australia and Hong Kong have seen personal benefits by being covered from the highest risk HPV strains.
HPV has also been shown to cause cancers in men. It has been shown to cause oral, anal, penile, genital and some head and neck cancers.
HPV-16 and HPV -18 have been linked with Oropharyngeal squamous cell carcinoma (OSCC). This form of cancer has been increasing worldwide, including in the UK, particularly among men and younger age groups. In Scotland the rate of OSCC has increased more than any other cancer.
Heterosexual boys and young men in countries with high rates of vaccination against HPV in girls receive an indirect benefit. Vaccinated female sexual partners do not have active HPV infections and so do not shed the virus for the young men to contract.
However, vaccinating only girls will not fully protect young men for several reasons. Firstly, not all girls will be vaccinated, especially in countries such as Hong Kong where having the vaccine is not mandatory and involves financial outlay by parents. A Lancet article from 2016 showed that in Europe, of the girls targeted by vaccination programmes only 52.8 per cent had been vaccinated, and in northern America it was only 39.3 per cent.
Secondly, it does not protect men who have sex with men. This population of men are also disproportionally affected by sexually transmitted infections including HIV, chlamydia, gonorrhea and syphilis.
Thirdly, girls will receive further protection against contracting HPV infection if boys are vaccinated. This has been mathematically modelled to reduce cervical cancer rates even further.
For this reason, in 2018 public health England introduced vaccinations against HPV for men who have sex with men. It is administered through sexual health clinics for men up to the age of 45. For some of these men, vaccination will have come too late and they will already have been exposed to a high-risk HPV virus, leaving them at risk of HPV related cancers
There is another approach to protecting young men against HPV related cancers and genital warts; Australia introduced vaccination for boys in 2013 and the UK is rolling out vaccination for boys aged 11-12 in schools from the coming school year. Older boys up to the age of 25 will also be able to access the vaccination.
Fact – vaccinations have helped eradicate 2 diseases worldwide, smallpox and a less well known cattle virus called rinderpest similar to measles.
BIO – Dr Harriet Stuart-Clarke works as a GP and can be consulted at Southside Family Health Centre.