A study of men who have sex with men in Ireland has suggested that vaccinating men who are already sexually active against the Human Papilloma Virus (HPV) may still be beneficial in protecting them against the cancer causing strains of the virus.
Previously cost-benefit analyses around the vaccine have suggested that it is only worth vaccinating children against HPV before they become sexually active.
However this new Irish research has found that there are many sexually active gay men who still do not carry some of the strains that available HPV vaccines protect against.
The researchers recruited 194 men who have sex with men from sexual health services aimed at gay men, with 99 of those HIV positive and 95 HIV negative.
77% of the HIV positive men and 61% of the HIV positive men were already infected with some strain of HPV – but only a minority had been infected with all three of the cancer causing strains of the virus that vaccines protect against.
Only 36% of the HIV negative men in the study were infected with the cancer causing HPB16, HPV18 or HPV31 strains, while only 47% of the HIV positive men were carrying those strains.
The HPV31 strain is not covered specifically by the existing HPV vaccines but they have been found to provide improved protection against it.
Only 12% of the HIV positive men in the study were found to be infected with both HPB16 and HPV18 and none of the HIV negative men had both cancer causing strains of the virus that existing HPV vaccines are targeted against.
The researchers also found that there was no difference in rates of infection with HPV between men who had anal sex and those who only have oral sex.
The study was released just days before the UK Government’s Joint Committee on Vaccination and Immunization met yesterday to discuss whether the HPV vaccine should be given to adolescent boys in Britain, and also whether it should be made available for gay men.
The study’s authors recommend that vaccination against HPV be extended beyond school aged boys and girls to include ‘targeted vaccination of high-risk groups such as MSM [men who have sex with men] and those with HIV infection.’
Australia began vaccinating males aged 14 to 15 in February of last year however no country has yet sought to systematically vaccinate sexually active adult gay men against the virus.
Cancer causing HPV strains have been linked to a third of all throat cancer cases and it is also responsible for causing genital and anal warts.