While these data suggest a potential utility of testing for the HPV DNA and antibody status before vaccinating older women who have already initiated sexual contacts [61],
current guidelines do not recommend screening with HPV testing because very few women have click here been exposed to all types in the vaccine, and protection against other vaccine types is not affected by the presence of infection with one vaccine type. Moreover, there is no evidence of clinical utility for HPV genotyping at young ages (<25 years), as nearly all HPV infections will clear spontaneously and unnecessary HPV testing could generate over-diagnosis and treatment [62,63]. Immunization of males. Immunization of boys with VLPs elicits a serum immune response similar to that in girls. Because genital HPV infection is sexually transmitted, immunization of men may help to prevent infection of women. Modelling studies on herd immunity, i.e. indirect protection of those who remain susceptible, owing to a reduced prevalence of infections in the risk group for disease, have been published check details [64–66]. The utility of immunization of males depends upon the assumed population coverage of vaccination, with successively smaller additional benefits seen in scenarios with high population coverage [67]. Modelling of programmes with high population coverage (90%) have found that addition of male vaccination gives a more rapid infection control
and have suggested that both sex vaccination programmes may be required to achieve an ultimate eradication of the infection [60]. Vaccination programme strategies as a randomized health-care policy. Design of HPV vaccination programmes has been based upon estimations of the impact of HPV vaccination on the burden of cervical cancer incidence and mortality using mathematical modelling of projected effects from the observed surrogate endpoint effects [59,67,68]. Whereas
clinical end-points are essential for estimates of effects on health economy, the control of HPV infections is a more immediately relevant cAMP end-point in models that compare different programme designs [60]. For programme design issues that are ambiguous, notably which age groups should be targeted and whether vaccination of males is required, randomization of vaccination programmes is an interesting option. That the incidence of cervical and other HPV-associated cancers does eventually decrease in vaccinated populations should then be verified by monitoring HPV incidences in sexually active youth groups and incidences of HPV-associated diseases by registry-based follow-up [69–72]. HPV types. Antibody responses elicited by VLP immunization are, in general, specific for the individual HPV type. However, lower titre cross-reactivity is noted for closely related HPV types [31,33,45,52] as well as partial protection against disease end-points associated with these non-vaccine types [35,73].