Development of a District-Level Programmatic Assessment Tool for Risk of Measles Virus Transmission

Abstract

All six World Health Organization (WHO) regions have now set goals for measles elimination by or before 2020. To prioritize measles elimination efforts and use available resources efficiently, there is a need to identify at-risk areas that are offtrack from meeting performance targets and require strengthening of programmatic efforts. This article describes the development of a WHO measles programmatic risk assessment tool to be used for monitoring, guiding, and sustaining measles elimination efforts at the subnational level. We outline the tool development process; the tool specifications and requirements for data inputs; the framework of risk categories, indicators, and scoring; and the risk category assignment. Overall risk was assessed as a function of indicator scores that fall into four main categories: population immunity, surveillance quality, program performance, and threat assessment. On the basis of the overall score, the tool assigns each district a risk of either low, medium, high, or very high. The cut-off criteria for the risk assignment categories were based on the distribution of scores from all possible combinations of individual indicator cutoffs. The results may be used for advocacy to communicate risk to policymakers, mobilize resources for corrective actions, manage population immunity, and prioritize programmatic activities. Ongoing evaluation of indicators will be needed to evaluate programmatic performance and plan risk mitigation activities effectively. The availability of a comprehensive tool that can identify at-risk districts will enhance efforts to prioritize resources and implement strategies for achieving the Global Vaccine Action Plan goals for measles elimination.

Keywords: Elimination; measles; outbreak; risk assessment.

Fig. 1.

Checklist of data sources required for the measles programmatic risk assessment tool: DPT1 = first dose in series for diphtheria, pertussis, and tetanus vaccination; MCV1 = first dose in series for measles-containing vaccination; MCV2 = second dose in series for measles-containing vaccination; SIA = supplementary immunization activity. (1) Vaccination coverage estimates from surveys if conducted within past three years and includes birth cohorts of recent three years that can be used to replace administrative coverage. (2) Outbreak response immunization (ORI) campaign coverage data can be considered if an SIA was not conducted within the past three years and if the ORI targeted a geographical area that included the entire district. (3) Presence of vulnerable groups includes any of the following: (i) migrant population, internally displaced population, slums, or tribal communities; (ii) communities resistant to vaccination (i.e., religious, cultural, philosophical reasons); (iii) security and safety concerns; (iv) areas frequented by calamities/disasters; (v) poor access to health services because of terrain/transportation issues; (vi) lack of local political support; (vii) high-traffic transportation hubs/major roads or bordering large urban areas (within and across countries); (viii) areas with mass gatherings (i.e., trade/commerce, fairs, markets, sporting events, and high density of tourists).

Fig. 2.

Measles risk assessment profiles in: (a) Senegal 2006–2008, (b) Namibia 2006–2008, and (c) the Philippines 2010–2012.