Vaccination coverage among migrants: A systematic review and meta-analysis

Background: Migrants, a population vulnerable to communicable diseases, face multiple barriers in access to immunization programs. Individual studies suggest that they suffer immunization inequity compared to non-migrants, but the gap in vaccination has not been quantified. This systematic review assessed quantitatively the level of vaccination coverage among migrants, in comparison with non-migrants, collating the published literature. Methods: Review protocol was prospectively registered (PROSPERO CRD42021228061). A literature search without language restrictions was conducted in PubMed, Scopus and Web of Science, from database inception to February 2021. This review included observational studies that provided the vaccination rates among migrant and non-migrant groups. Study quality was assessed using Newcastle-Ottawa scale. Data were synthesized pooling data from individual studies to generate summary odds ratio (OR) with 95% confidence interval (CI) using random effects model, assessing heterogeneity with I2 statistic and publication bias with funnel asymmetry analysis. Findings: There were 44 relevant studies (7,937,996 participants). Overall risk of bias was low in 13 (30%), moderate in 22 (50%) and high in 9 (20%) studies. Point estimates of individual ORs showed lower vaccination coverage among migrants in 36 of 39 meta-analyzable studies. Overall, the odds of vaccination coverage among migrants were lower compared to non-migrants (7,375,184 participants; summary OR 0.50; 95% CI 0.37–0.66; I2 99.9%). There was no funnel asymmetry. Interpretation: Migrants are half as often vaccinated compared to non-migrants. Public health prevention programs need to prioritize vaccination equity, not just to protect migrants but also to protect the host communities (AU)

Antecedentes: Los migrantes, una población vulnerable a enfermedades transmisibles, se enfrentan a múltiples barreras en el acceso a los programas de inmunización. Estudios individuales sugieren que este colectivo poblacional sufre desigualdad en la cobertura de inmunización, en comparación con población no migrante; sin embargo, hasta el momento no se ha cuantificado la brecha en la cobertura de vacunación. Esta revisión sistemática evaluó cuantitativamente el nivel de cobertura de vacunación entre los migrantes, en comparación con los no migrantes, recopilando la literatura publicada. Métodos: El protocolo de revisión fue registrado prospectivamente (PROSPERO CRD42021228061). Se realizó una búsqueda de literatura sin restricciones de idioma en PubMed, Scopus y Web of Science, desde el inicio de las bases de datos hasta febrero de 2021. Esta revisión incluyó estudios observacionales que proporcionaran coberturas de vacunación entre grupos de migrantes y no migrantes. La calidad de los estudios se evaluó mediante la escala Newcastle-Ottawa. Los datos se sintetizaron y se extrajeron los valores de odds ratio (OR) e intervalo de confianza (IC) del 95%, utilizando un modelo de efectos aleatorios para cada uno de los estudios incluidos. Finalmente, se evaluó la heterogeneidad de los mismos con la prueba estadística de I2 y, el sesgo de publicación con el análisis de asimetría de embudo. Resultados: Hubo 44 estudios relevantes (7.937.996 participantes). El riesgo de sesgo fue bajo en 13 (30%), moderado en 22 (50%) y alto en nueve (20%) estudios. Las estimaciones puntuales de las OR individuales mostraron una menor cobertura de vacunación entre los migrantes en 36 de 39 estudios metaanalizables. En general, las probabilidades de cobertura de vacunación entre los migrantes fueron menores, en comparación con los no migrantes (7.375.184 participantes; OR resumen 0,50; IC 95%: 0,37-0,66; I2 99,9%)s (AU)

Vaccination coverage among migrants: A systematic review and meta-analysis.

BACKGROUND: Migrants, a population vulnerable to communicable diseases, face multiple barriers in access to immunization programs. Individual studies suggest that they suffer immunization inequity compared to non-migrants, but the gap in vaccination has not been quantified. This systematic review assessed quantitatively the level of vaccination coverage among migrants, in comparison with non-migrants, collating the published literature. METHODS: Review protocol was prospectively registered (PROSPERO CRD42021228061). A literature search without language restrictions was conducted in PubMed, Scopus and Web of Science, from database inception to February 2021. This review included observational studies that provided the vaccination rates among migrant and non-migrant groups. Study quality was assessed using Newcastle-Ottawa scale. Data were synthesized pooling data from individual studies to generate summary odds ratio (OR) with 95% confidence interval (CI) using random effects model, assessing heterogeneity with I2 statistic and publication bias with funnel asymmetry analysis. FINDINGS: There were 44 relevant studies (7,937,996 participants). Overall risk of bias was low in 13 (30%), moderate in 22 (50%) and high in 9 (20%) studies. Point estimates of individual ORs showed lower vaccination coverage among migrants in 36 of 39 meta-analyzable studies. Overall, the odds of vaccination coverage among migrants were lower compared to non-migrants (7,375,184 participants; summary OR 0.50; 95% CI 0.37-0.66; I2 99.9%). There was no funnel asymmetry. INTERPRETATION: Migrants are half as often vaccinated compared to non-migrants. Public health prevention programs need to prioritize vaccination equity, not just to protect migrants but also to protect the host communities.