Human papillomavirus vaccines
Human papillomavirus vaccines
Human papillomavirus (HPV) infection is a common infection in HIV-infected adults. The virus is more prevalent and persistent in HIV-infected adults. The persistence of certain serotypes of HPV infection is associated with squamous dysplasia and cancer 60. In 2008 it was estimated that of the 12.7 million new cancers that occurred worldwide, around 5% were attributable to HPV infection 60,61. The highest burden of HPV infection and associated diseases is carried by women 60,62.
HPV vaccines are safe and immunogenic in HIV-infected adults 63. As observed with other vaccines, HPV vaccine-induced immune responses are better in HIV-infected subjects with CD4+ cell counts greater than 200 cells/μL and suppressed viral loads. There are limited data on the efficacy and durability of protection provided by HPV vaccines in HIV-infected adults, whether vaccinated before or after acquisition of HIV infection. There is also no evidence to guide booster vaccine dosing in HIV-infected individuals 60.
In South Africa, HPV vaccination is routinely recommended for preteen girls aged 9-13 years, regardless of HIV status. HPV vaccination is recommended for all HIV-infected adult men and women, MSM aged up to 40 years, regardless of CD4+ count, ART use or viral load. In the public sector in South Africa, the bivalent vaccine is currently in use. In the private sector the quadrivalent 4-valent HPV vaccine (4vHPV) is also available. The 4vHPV was originally tested and approved as a 3-dose regimen, with a dosing schedule of 0, 2 and 6 months. More recently a 2-dose schedule (6 or 12 months apart) has been recommended by the World Health Organization for younger age groups (e.g. 9-14 years at first dose). This is because immunogenicity with two doses in preadolescent and early adolescent girls was non-inferior to antibody responses in women 16-26 years receiving three doses 64,65. Should the vaccine schedule be interrupted, it is recommended that the vaccination series be completed, rather than restarted 28.