Young men and adolescent boys between the ages of 11 and 21
should be vaccinated against human papillomavirus, the cause of genital warts,
anal and cervical cancer, the Advisory Committee on Immunization Practices has
recommended, in a new Adult Immunization Schedule published in Annals of Internal Medicine.
The committee also recommends that all gay and bisexual men
and HIV-positive men aged 26 and under should be vaccinated.
US guidelines already recommend that young women and girls
aged 11 to 26 should receive the vaccination.
In the United Kingdom, HPV vaccination is offered to girls
aged 12 and 13 through a National Health Service vaccination programme, although
girls in the 14-to-17 age group can also be vaccinated.
At present, the only HPV vaccine licensed for use in males is
Gardasil, manufactured by Merck,
which protects against four cancer-causing types of HPV (types 6, 11, 16 and
18). Gardasil is licensed for use in
boys aged 9 to 15 years in the United
Kingdom.
Vaccination has been shown to reduce the subsequent risk of
genital warts, pre-cancerous cervical changes and cervical cancer in women. In
young men, the vaccine has been shown to reduce the risk of HPV infection.
In an accompanying editorial, Dr Sandra Fryhofer of Emory University,
Atlanta, notes
that although clinical data are not available, the rationale that vaccination
also protects against oropharyngeal cancers caused by HPV is “certainly
plausible”.
A recent review of the impact of HPV vaccination in
Melbourne, Australia, found that the risk of young men and women under 21 being
diagnosed with genital warts fell by approximately 60% between 2007/8 and
2010/11 among patients attending the Melbourne Sexual Health Centre. This
followed the implementation of a vaccination programme in girls and women aged
26 and under from 2007 onwards.
The number of sexual partners did not affect the reduction
in risk.
In contrast, new diagnoses of genital warts did not fall
significantly in heterosexual women and men aged 30 and over, nor in men who
have sex with men, indicating that these groups are not benefiting from the
effect of the current vaccination policy.