Preventive medicine
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Preventive medicine · Mar 2021
ReviewElimination of cervical cancer: Lessons learned from polio and earlier eradication programs.
This paper reviews definitions of control, elimination, and eradication and considers lessons learned from prior and current elimination/eradication efforts that might inform the current effort to eliminate cervical cancer. This task is complicated by the varying definitions of elimination extant. Lessons for cervical cancer elimination notably include the necessity for political will/champions; the need for a specific target with a time span; the need for program efforts to be guided by surveillance of disease and death (not just coverage); the need for accountability, monitoring, and evaluation at all levels; and the need for ongoing research. Although achieving the goal of elimination will be difficult, success will mean the prevention of millions of deaths due to cervical cancer.
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Preventive medicine · Mar 2021
HPV vaccination introduction worldwide and WHO and UNICEF estimates of national HPV immunization coverage 2010-2019.
WHO/UNICEF estimates for HPV vaccination coverage from 2010 to 2019 are analyzed against the backdrop of the 90% coverage target for HPV vaccination by 2030 set in the recently approved global strategy for cervical cancer elimination as a public health problem. As of June 2020, 107 (55%) of the 194 WHO Member States have introduced HPV vaccination. The Americas and Europe are by far the WHO regions with the most introductions, 85% and 77% of their countries having already introduced respectively. ⋯ When expressed as world population coverage (i.e., weighted by population size), global coverage of the final HPV dose for 2019 is estimated at 15%. There is a long way to go to meet the 2030 elimination target of 90%. In the post-COVID era attention should be paid to maintain the pace of introductions, specially ensuring the most populous countries introduce, and further improving program performance globally.
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Preventive medicine · Mar 2021
Achieving equity in cervical cancer screening in low- and middle-income countries (LMICs): Strengthening health systems using a systems thinking approach.
The World Health Organization (WHO) is leading a call to action to eliminate cervical cancer by the end of the century through global implementation of two effective evidence-based preventive interventions: HPV vaccination and cervical screening and management (CSM). Models estimate that without intervention, over the next 50 years 12.2 million new cases of cervical cancer will occur, nearly 60% of which are preventable only through CSM. Given that more than 80% of the cervical cancer occurs in low- and middle-income countries (LMICs), scaling up sustainable CSM programs in these countries is a top priority for achieving the global elimination goals. ⋯ As part of the coordinated cervical cancer elimination effort, we applied a systems thinking lens to reflect on our experiences with implementation of HPV-based CSM programs using the WHO health systems framework. While many common health system barriers were identified, the effectiveness of implementation strategies to address them was context dependent; often reflecting differences in stakeholder's belief in the quality of the evidence supporting a CSM algorithm, the appropriateness of the evidence and algorithm to context, and the 'implementability' of the algorithm under realistic assessments of resource availability and constraints. A structured planning process, with early and broad stakeholder engagement, will ensure that shared-decisions in CSM implementation are appropriately aligned with the culture, values, and resource realities of the setting.
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Preventive medicine · Mar 2021
Surveillance systems for monitoring cervical cancer elimination efforts: Focus on HPV infection, cervical dysplasia, cervical screening and treatment.
In order to achieve the global elimination of cervical cancer as a public health problem, close surveillance of progress in public health and clinical activities and outcomes across the three pillars of vaccination, screening and treatment will be required. Surveillance should ideally occur within an integrated system that is planned, funded, and regularly evaluated to ensure it is providing timely, accurate and relevant feedback for action. In this paper, we conceptualise the main public health surveillance objectives as process and outcome measures in each of the three pillars. ⋯ Outcome measures related to the natural history of human papillomavirus (HPV) infection include HPV infection prevalence, precursor cervical lesions and cervical cancers (including stage at diagnosis, cancer incidence and mortality). These outcome measures can be used for monitoring the effectiveness of the three core activities in the short, medium and long term to assess whether these interventions are effectively reducing their occurrence. We discuss possible methods for the surveillance of these measures in the context of country capacity, drawing from examples in Australia, the USA and in low and middle income countries.
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Preventive medicine · Mar 2021
Impact and cost-effectiveness of strategies to accelerate cervical cancer elimination: A model-based analysis.
Following the global call for action by the World Health Organization to eliminate cervical cancer (CC), we evaluated how each CC policy decision in Norway influenced the timing of CC elimination, and whether introducing nonavalent human papillomavirus (HPV) vaccine would accelerate elimination timing and be cost-effective. We used a multi-modeling approach that captured HPV transmission and cervical carcinogenesis to estimate the CC incidence associated with six past and future CC prevention policy decisions compared with a pre-vaccination scenario involving 3-yearly cytology-based screening. Scenarios examined the introduction of routine HPV vaccination of 12-year-old girls with quadrivalent vaccine in 2009, a temporary catch-up program for females aged up to 26 years in 2016-2018 with bivalent vaccine, the universal switch to bivalent vaccine in 2017, expansion to include 12-year-old boys in 2018, the switch from cytology- to HPV-based screening for women aged 34-69 in 2020, and the potential switch to nonavalent vaccine in 2021. ⋯ Cumulatively, subsequent policy decisions accelerated elimination to 2039. According to our modeling assumptions, switching to the nonavalent vaccine would not be considered 'good value for money' at relevant cost-effectiveness thresholds in Norway unless the incremental cost was $19 per dose or less (range: $17-24) compared to the bivalent vaccine. CC control policies implemented over the last decade in Norway may have accelerated the timeframe to elimination by more than 17 years and prevented over 23,800 cases by 2110.