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www.thelancet.com Vol 374 October 17, 2009 1329 and women, ”reducing the incidence of genital warts, cervical intraepithelial neoplasia, and cervical cancer by 97%, 91%, and 91%, respectively”. Although the initial expense will be higher, additionally accounting for the prevention of HPV-linked cancers in men (eg, anal, penile, and oropharyngeal cancers) will make this approach cost eff ective. The eventual eradication, or even a drastic reduction in the rate of HPV infections, will require vaccination of both sexes. The results of HPV vaccination of people with previous HPV 16 or 18 infection have to be interpreted with caution. Contrary to what Michele Manos suggests, any diff erences in cervical intraepithelial neoplasia of grade 2 or above (CIN2+) between vaccinated and non-vaccinated women were non-signifi cant, and only 3% of the study population was both HPV 16/18 DNA-positive and seropositive. Antibody-dependent exacerbation of viral infections seems to mainly concern specifi c RNA viruses, such as feline coronavirus, dengue virus, and feline immunodefi ciency virus. Currently, there is little evidence that antibody-dependent exacerbation facilitates HPV infection, particularly since the presently available vaccines against high-risk HPV types seem to neutralise viral particles before cell entry. Although Manos considers the eradication of HPV infections a “noble goal”, the development of HPV vaccines was unnecessarily delayed by doubts about the causal role of HPV infections in cervical cancer. We do not have to wait for more detailed immunological studies before we start planning large-scale interventions, since they will be highly eff ective public health programmes. Without a strategic vision, global programmes will not be started.