Populations At Risk For Severe Or Complicated Measles: A Systematic Review

Measles is a highly contagious systemic infection that can affect the skin, eyes, gut and respiratory system, and can be associated with severe complications occur in about one third of cases and may arise up to one month after infection. The risk of severe or complicated measles (ex. pneumonia, encephalitis, severe diarrhoea/dehydration, and pregnancy-related adverse outcomes) varies substantially by host factors such as age and comorbidity, with higher risk consistently described among young children, pregnant persons, and individuals who are malnourished (including vitamin A deficiency) or immunocompromised (ex. HIV). The objectives are to identify studies describing groups at risk for severe or complicated measles illness and to provide summary estimates of risk, supporting risk stratification to guide policy and clinical decisions and informing policy decisions about targeted prevention strategies and resource allocation in outbreak response, post-exposure prophylaxis, clinical triage, and health-system planning.