Health equity and system resilience during crises - ensuring healthcare for refugees based on lessons from Iran's response to the 2021 Afghan migration.

Background: Sudden influxes of displaced populations can strain health systems, especially in low- and middle-income countries. Iran hosts one of the world's largest migrant and refugee populations -predominantly from Afghanistan - and provides inclusive access to public health and education services. In August 2021, the crisis in Afghanistan triggered a sharp increase in Afghan arrivals to Iran, raising healthcare demand amid the COVID-19 pandemic. This study examines how one of the largest public health networks in Tehran responded to this surge and the resulting impact on equitable service coverage and system resilience.

Methods: We retrospectively analyzed monthly healthcare utilization data over a 13-month period (February 2021-February 2022) from the largest public health network in western Tehran, which serves approximately 5.5 million residents, including nearly 1 million migrants and refugees. Patients were categorized into six demographic subgroups: children, women of childbearing age, adolescents, young adults, middle-aged adults, and the elderly. Changes in the number and proportion of patients receiving the full Essential Health Service Package (EHSP) were assessed using six-month pre-/post-event comparisons, with statistical significance determined via chi-square tests (p < 0.05).

Results: The total number of patients served increased eight-fold, from 88,091 in February 2021 to 717,382 in February 2022. In the six-month period following the crisis, the number of Afghan patients receiving full EHSP coverage rose by 84,522; however, the proportion of full-service coverage declined by 3.2%. Children were the most affected subgroup: despite 2,739 additional patients receiving full services, their coverage rate fell by 10.6%. In contrast, young Afghan adults experienced an increase in both number and proportion of patients receiving full services (+ 25,421, + 1.2%). All subgroup changes were statistically significant (p < 0.001).

Conclusions: Although the public health network rapidly expanded service delivery, maintaining proportional coverage for full services proved challenging, particularly for vulnerable groups. Even established health systems with decades of experience in serving displaced populations may face transient coverage shortfalls amid demand surges compounded by pandemic-related strain. Strengthening public health emergency management through targeted resource allocation, surge capacity, and real-time monitoring of coverage indicators is essential to sustaining health equity and system resilience during future crises.