Human papillomavirus vaccination in national immunization programs: impact and perspectives

Abstract

Human Papillomaviruses are present in virtually all cases of cervical cancer and are also linked with anogenital warts and other precancerous lesions which can be primarily prevented by HPV vaccination. We searched the PubMed, Scopus, Web of Science and Embase databases (between January 1st, 2011 and February 28th, 2017) and WHO (World Health Organization) and countries’ health organizations websites for data on HPV vaccination programs and its effectiveness. For the review on the Brazilian Immunization program, we additionally searched SciELO database and websites of the Brazilian Ministry of Health and the Information System of the National Immunization Program (SI-PNI). As of April 2017, about 40% of the countries had introduced HPV vaccines in their national immunization programs, targeting almost always children and teenage females between 9 and 13 years of age. Most of these are high-income countries but low- and middle-income countries are recently implementing the vaccination program with financial support of public and private organizations. Since the introduction of HPV vaccination, numerous articles present data on its effectiveness in real world supporting the effectiveness of an immunization program in the prevention of HPV infection and related diseases in both genders. The Brazilian HPV vaccination program began in 2014 for 9-13 years old girls and has recently been expanded to include boys and young males. This review aims to update information on HPV vaccination programs worldwide highlighting the Brazilian immunization program. Data on the impact and effectiveness of HPV vaccines on infection and related diseases is presented. Moreover, the reasons for different coverage rates, reflected in low-vaccine uptake, are discussed. Finally, the present review addresses the socioeconomic barriers as well as the key determinants of long-term program success and strategies to improve access and adherence to HPV vaccination.