Pryanka Relan, Jamie Rylance, Yaseen M Arabi, Pauline Convocar, Matthieu Rolland, Janet V Diaz on behalf of the O2CoV2 investigators*

Summary
Background The COVID-19 pandemic highlighted a global shortage of, and inequity of access to, medical oxygen.
Understanding patient outcomes and the capacities of health facilities to provide respiratory support including
oxygen is key to matching need and demand. We report results from a global study including 23 low-income and
middle-income countries.

Methods For this prospective, observational cohort study, consecutive patients aged 12 years or older with suspected or confirmed COVID-19 and evidence of respiratory distress were prospectively recruited within 24 h of hospital admission. Hospitals from 23 low-income and middle-income countries were included, representing all WHO regions.
Baseline demographic and clinical data were collected, and daily follow-ups were recorded for in-hospital outcomes and respiratory support types. At the facility level, we assessed sources of oxygen and electricity, infrastructural and staffing capacity for critical care provision, and the capabilities of the facility for advanced respiratory support. The primary outcome was 30-day in-hospital mortality. This study was registered on ClinicalTrials.gov (NCT04918875).

Findings Between Jan 24 and Nov 22, 2022, 56 sites took part. Of 53726 patients screened, 3070 were enrolled.
1814 (61·6%) of 2947 patients had two or more underlying medical conditions and initially received oxygen through nasal cannula or non-rebreather face masks with reservoir. Invasive mechanical ventilation was most frequently used in patients recruited in the Americas (75 [26·4%] of 284 patients) and in the Eastern Mediterranean (90 [18·0%] of 499 patients). The overall mortality was 649 (23·4%) of 2779 patients, varying by region from 53 (10·5%) of 506 patients in South-East Asia to 286 (37·6%) of 760 patients in Africa. Mortality was associated with the maximum level of respiratory support received: from 17 (8·6%) of 198 patients who received no oxygen, 99 (38·4%) of 258 patients for non-rebreather reservoir bags, and 205 (62·9%) of 326 for invasive ventilation.

Interpretation The availability and use of oxygen support options in low-income and middle-income countries are
highly variable but appear significantly less in the African region. Mortality might be associated with a lack of access to oxygen, which varied across WHO regions but was highest in Africa. Despite many lessons learned from the COVID-19 pandemic, inequity in access to medical oxygen remains a challenge that WHO and partners must address in the post-pandemic era to avoid preventable deaths.

Funding UNITAID.

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www.thelancet.com/lancetgh Vol 14 February 2026