Background: The Integrated Management of Childhood Illness (IMCI) guidelines is a symptom-based
algorithm guiding healthcare workers in resource-limited countries to identify critically ill children
under-5 in primary healthcare centre (PHC). Hypoxemia, a life-threatening event, is often clinically
underdiagnosed. The AIRE project has implemented the routine use of Pulse Oximeter (PO) in IMCI
consultations to improve the diagnosis of severe hypoxemia (SpO2 < 90%) and the management of
severe cases at PHC level in Burkina Faso, Guinea, Mali and Niger. We measured the prevalence of
IMCI+PO severe cases, and their associated social and structural factors among IMCI outpatients.
Methods: In 16 AIRE research PHC (4/country), all the children under-5 attending IMCI consultations,
except those aged 2-59 months classified as simple case without cough or breathing difficulties, were
eligible for PO use and enrolled in a cross-sectional study with parental consent. Severe IMCI+PO cases
were defined as IMCI severe cases or those with severe hypoxemia.
Results: From June 2021 to June 2022, 968 neonates (0-59 days) and 14,868 children (2-59 months)
were included. Prevalence of severe IMCI+PO cases was heterogeneous between countries: 5.0% in
Burkina Faso, 6.1% in Niger, 18.9% in Mali and 44.6% in Guinea. Among neonates, 21.9% (95%CI: 19.3
24.6) were classified as IMCI+PO severe cases versus 12.0% (95%CI: 11.4-12.5) in older children. Severe
hypoxemia was identified in 3.3% of neonates versus 0.8% in older children (p<0.001). The adjusted
social and structural factors associated with disease severity commons to all four countries were: age
<2 months or >2 years, IMCI-consultation delay >2 days, home to PHC travel time >30 minutes.
Conclusion: Despite between-country heterogeneity, the prevalence of seriously ill children under-5
including severe hypoxemia was high, particularly in neonates, and those without accessibility to PHC.
Improving earlier access to primary healthcare and management of severe cases remains needed in
West Africa.

Severe illness, Pulse Oximeter, Primary Health Care, Children under-5, West Africa