RESUMEN
More than 90% of cervical cancer deaths occur in low- and middle-income countries (LMICs), which have limited capacity to mount the comprehensive national screening and precancer treatment programs that could prevent most of these deaths. The development of vaccines against the human papillomavirus (HPV) has dramatically altered the landscape of cervical cancer prevention. As of mid-2020, 56 LMICs (41% of all LMICs) have initiated national HPV vaccination programs. This paper reviews the experience of LMICs that have introduced HPV vaccine into their national programs, key lessons learned, HPV vaccination sustainability and scale-up challenges, and future mitigation measures. As international guidance evolved and countries accumulated experience, strategies for national introduction shifted with regard to target groups, delivery site and timing, preparation and planning, communications and social mobilization, and ultimately monitoring, supervision and evaluation. Despite the successes that LMICs have been able to achieve in reaching large proportions of eligible girls, there are still considerable challenges countries encounter in overcoming rumors, reaching out-of-school girls, completing the vaccine series, estimating target populations, monitoring program performance, and assuring vaccination sustainability. New opportunities, such as the entry of additional vaccine manufacturers and ongoing studies to evaluate one-dose delivery, could help overcome the outstanding barriers to higher coverage and financial sustainability. Effective use of the experience to date and advances on the horizon could enable all LMICs to move towards the coverage levels that are needed to achieve eventual elimination.
Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Países en Desarrollo , Femenino , Humanos , Programas de Inmunización , Infecciones por Papillomavirus/prevención & control , Neoplasias del Cuello Uterino/prevención & control , VacunaciónRESUMEN
Persistent oncogenic human papillomavirus (HPV) is the cause of cervical cancer, as well as cancers of the anus, penis, vulva, vagina and oropharynx. There is good evidence that prophylactic HPV vaccines are immunogenic and effective against targeted-type HPV infections and type-specific genital lesions, including high-grade cervical intraepithelial neoplasia (CIN), when administered prior to HPV infection. There is good evidence that HPV vaccines are safe in population usage, with the most frequent adverse event being injection-site reactions. There is evidence to support some cross-protection against non-targeted types occurring following the administration of HPV vaccines. There is limited evidence suggesting that HPV vaccines may be beneficial in preventing future disease in women treated for high-grade CIN. This chapter focuses on the accumulated evidence regarding the global use of the three licensed HPV vaccines including safety, immunogenicity, duration of protection, effectiveness, coverage to date and barriers to higher coverage.