Post‑Measles Complications and Mortality in Children under Five Years in Low‑ and Middle‑Income Countries: A Narrative Review

Background: Global measles vaccination programs have achieved significant reductions in measles‑related mortality, with World Health Organization (WHO)‑led initiatives expanding vaccine coverage to over 85% of children worldwide. Despite this progress, measles elimination remains elusive, undermined by anti‑vaccine sentiment, armed conflicts, migration, refugee crises, and post‑COVID‑19 disruptions. No WHO region has achieved or sustained measles elimination status since the COVID‑19 pandemic, and elimination remains challenging in resource‑limited and conflict‑affected contexts. A critical yet underappreciated consequence of this ongoing burden is the rise of post‑measles complications (PMCs). Vaccine‑preventable diseases and malnutrition constitute two critical global health priorities; PMCs represent an important intersection of these agendas that warrant greater attention within the global health framework.

Objectives: To review and synthesize current epidemiological evidence on PMCs, examine their pathogenesis, and understand the need for integrated post‑measles care strategies in vulnerable populations.

Methods: This narrative review included all papers that published primary data on any of the PMCs in the last 55 years, identified through PubMed and Google Scholar.

Findings: Epidemiological data show that 30–40% of measles cases in low‑ and middle‑income countries (LMICs) develop complications, including pneumonia, diarrhea, otitis media, and, less commonly, encephalitis and ocular disease. PMCs are frequently misattributed to independent illnesses because they often emerge after a delay following the acute infection. Compounding this, measles‑induced immune amnesia renders affected individuals vulnerable to secondary infections for up to 2–3 years post‑infection. In LMICs and conflict‑affected settings, this prolonged immunological vulnerability intersects with pre‑existing risk factors such as malnutrition, micronutrient deficiencies, and poor healthcare access, which amplify the consequences substantially.

Conclusions: As measles cases resurge globally, the associated burden of PMCs is expected to increase correspondingly. Where PMCs represent a pressing, underaddressed concern, integrated post‑measles care strategies are urgently needed from a global health perspective, especially in resource‑limited and conflict‑affected settings.