A narrative review of high-level isolation unit operational and infrastructure features

High-level isolation units (HLIUs) are specially designed facilities for care and management of patients with suspected or confirmed high-consequence infectious diseases (HCIDs), equipped with unique infrastructure and operational features. While individual HLIUs have published on their experiences caring for patients with HCIDs and two previous HLIU consensus efforts have outlined key components of HLIUs, we aimed to summarise the existing literature that describes best practices, challenges and core features of these specialised facilities. A narrative review of the literature was conducted using keywords associated with HLIUs and HCIDs. A total of 100 articles were used throughout the manuscript from the literature search or from alternate methods like reference checks or snowballing. Articles were sorted into categories (eg, physical infrastructure, laboratory, internal transport); for each category, a synthesis of the relevant literature was conducted to describe best practices, experiences and operational features. The review and summary of HLIU experiences, best practices, challenges and components can serve as a resource for units continuing to improve readiness, or for hospitals in early stages of developing their HLIU teams and planning or constructing their units. The COVID-19 pandemic, a global outbreak of mpox, sporadic cases of viral haemorrhagic fevers in Europe and the USA, and recent outbreaks of Lassa fever, Sudan Ebolavirus, and Marburg emphasise the need for an extensive summary of HLIU practices to inform readiness and response.