RESUMO
Cervical cancer is currently the fourth leading cause of cancer death among women worldwide, with most cases occurring in low- and middle-income countries. Safe, highly effective vaccines against HPV have been on the market since 2006, yet only 6% of girls worldwide have received this life-saving cancer prevention intervention. International organizations, including PATH, Gavi, and the pharmaceutical companies Merck and GlaxoSmithKline, have provided support to eligible low- and middle-income countries to implement national HPV vaccination programs. Still, glaring disparities in the availability of national HPV vaccination programs and the coverage of the primary target population between the global north and south persist. We illustrate worldwide HPV vaccine implementation and coverage using an online data visualization, which is publicly available and can be used to gain unique insights. We also present three emerging solutions to transform future HPV vaccine delivery in low- and middle-income countries: low-cost generics, single-dose vaccination, and co-administration with other adolescent vaccines. By rapidly expanding access to HPV vaccination to girls everywhere, vaccine-type HPV infections can be virtually eliminated. At high vaccination-coverage levels, more than 80%-or approximately 230 000-of the cervical cancer deaths that occur each year can be averted.
Assuntos
Programas de Imunização , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/provisão & distribuição , Neoplasias do Colo do Útero/prevenção & controle , Adolescente , Feminino , Saúde Global , Humanos , Neoplasias do Colo do Útero/virologia , VacinaçãoRESUMO
Background:Sub-Saharan Africa bears a disproportionate burden of preterm birth and other adverse outcomes. A better understanding of the demographic, clinical, and biologic underpinnings of these adverse outcomes is urgently needed to plan interventions and inform new discovery. Methods:The Zambian Preterm Birth Prevention Study (ZAPPS) is a prospective observational cohort established at the Women and Newborn Hospital (WNH) in Lusaka, Zambia. We recruit pregnant women from district health centers and the WNH and offer ultrasound examination to determine eligibility. Participants receive routine obstetrical care, lab testing, midtrimester cervical length measurement, and serial fetal growth monitoring. At delivery, we assess gestational age, birthweight, vital status, and sex and assign a delivery phenotype. We collect blood, urine, and vaginal swab specimens at scheduled visits and store them in an on-site biorepository. In September 2017, enrollment of the ZAPPS Phase 1 - the subject of this report - was completed. Phase 2 - which is limited to HIV-uninfected women - reopened in January 2018. Results:Between August 2015 and September 2017, we screened 1784 women, of whom 1450 (81.2%) met inclusion criteria and were enrolled. The median age at enrollment was 27 years (IQR 23-32) and thee median gestational age was 16 weeks (IQR 13-18). Among parous women (N=866; 64%), 21% (N=182) reported a prior miscarriage, 49% (N=424) reported a prior preterm birth, and 13% (N=116) reported a prior stillbirth. The HIV seroprevalence was 24%. Discussion:We have established a large cohort of pregnant women and newborns at the WHN to characterize the determinants of adverse birth outcomes in Lusaka, Zambia. Our overarching goal is to elucidate biological mechanisms in an effort to identify new strategies for early detection and prevention of adverse outcomes. We hope that findings from this cohort will help guide future studies, clinical care, and policy.
RESUMO
BACKGROUND: Women infected with HIV have a risk of preterm birth (PTB) that is twice that among uninfected women, and treatment with antiretroviral therapy (ART) may further increase this risk. Progesterone supplementation reduces the risk of preterm delivery in women who have a shortened cervix in the midtrimester. We propose to study the feasibility of a trial of vaginal progesterone (VP) to prevent PTB among HIV-infected women receiving ART in pregnancy. Given low adherence among women self-administering vaginal study product in recent microbicide trials, we plan to investigate whether adequate adherence to VP can be achieved prior to launching a full-scale efficacy trial. METHODS AND DESIGN: One hundred forty HIV-infected pregnant women in Lusaka, Zambia, will be randomly allocated to daily self-administration of either VP or matched placebo, starting between 20 and 24 gestational weeks. The primary outcome will be adherence, defined as the proportion of participants who achieve at least 80% use of study product, assessed objectively with a validated dye stain assay that confirms vaginal insertion of returned single-use applicators. Secondary outcomes will be study uptake, retention, and preliminary efficacy. We will concurrently perform semi-structured interviews with participants enrolled in the study and with women who decline enrollment to assess the acceptability of VP to prevent PTB and of enrollment to a randomized controlled trial. DISCUSSION: We hypothesize that VP could prevent PTB among women receiving ART in pregnancy. In preparation for a trial to test this hypothesis, we plan to assess whether participants will be adherent to study product and protocol. TRIAL REGISTRATION: ClinicalTrial.gov, NCT02970552.