Trends and Predictors of Measles Immunisation Inequalities Among Children Aged 12–23 Months in the Philippines, 2008–2022 — The Association Specialists
Trends and Predictors of Measles Immunisation Inequalities Among Children Aged 12–23 Months in the Philippines, 2008–2022 (23809)
John Carlo Lorenzo12
, Carla Ante-Orozco3
, Md Irteja Islam1
, Erin Mathieu1
School of Public Health, The University of Sydney, Sydney, NSW, Australia
Sydney Infectious Diseases Institute, The University of Sydney, Sydney, NSW, Australia
Health and Nutrition, UNICEF Philippines, Manila, National Capital Region, Philippines
Background: The Philippines continues to experience measles outbreaks with declining coverage of the first dose of the measles vaccine (MCV1). Despite various interventions and policies to improve MCV1 coverage, inequalities persist, influenced by various socio-demographic factors. This study aims to identify predictors and examine trends in socio-economic inequalities in MCV1 receipt.
Methods: Using the four most recent Philippine DHS datasets (2008, 2013, 2017, and 2022), we identified predictors of MCV1 receipt through bivariate and multivariable regression models. We examined trends in socio-economic inequalities in MCV1 using the Slope Index of Inequality (SII) and Relative Index of Inequality (RII).
Results: Our study included 5,584 children aged 12–23 months. Overall MCV1 coverage declined from 84.7% (2008) to 80.8% (2022). Significant predictors of MCV1 receipt included household wealth quintile, maternal education, number of under-five children in a household, ANC visits, distance to health facility, and maternal smoking status. Socio-economic inequalities in MCV1 decreased from 2008 (SII=0.27; RII=1.41) to 2013 (SII=0.23; RII=1.33), stagnated in 2017 (SII=0.23; RII=1.35), and increased markedly in 2022 (SII=0.31; RII=1.52). Health system constraints including inadequate vaccine supply, suboptimal cold chain infrastructure, and limited trained immunisation staff disproportionately affected disadvantaged communities. Data limitations at the level of community health centre hinders regular monitoring of vaccine equity within catchment areas. Public health crises including the 2017 Dengvaxia controversy has eroded public trust in vaccines, while recurrent measles outbreaks and the COVID-19 pandemic further disrupted access to measles immunisation program.
Conclusion: Sustaining and monitoring equity-focused interventions guided by the National Immunisation Technical Advisory Groups, strengthening primary healthcare through Universal Health Coverage, and rebuilding community trust through community-focused initiatives are essential to ensuring measles vaccines remain available, accessible, and acceptable to disadvantaged communities affected by measles outbreaks and immunisation inequalities.